Guia Para Juntas de Construccion

ACI 504R-90

(Reapproved 1997)

Guide to Sealing Joints in ConcreteReported by ACI Committee 504*

Milton D. Anderson

Bert E. Colley

John P. CookRobert V. Costello

Edward R. Fyfe

Frank D. Gaus

Guy S. Puccio

Chairman

T. Michael Jackson

Charles S. Gloyd

Arthur Hockman

George HoreczkoVincent Kazakavich

Oswin Keifer, Jr.

Frank Klemm

Joseph F. Lamond

SecretaryPeter Marko

Joseph A. McElroyLeroy T. Ohler

Chris Seibel. Jr.

Peter Smith

Stewart C. Watson

*The Committee wishes to recognize the important contribution of the currentchairman, Sherwood Spells, to the development of this guide.

Most joints, and some cracks in concrete structures, require sealing

against the adverse effects of environmental and service conditions.

This report is a guide to better understanding of the properties of joint

sealants and to where and how they are used in present practice.

Described and illustrated are: The functioning of joint sealants; re-

quired properties, available materials and applicable specifications for

field-molded sealants and preformed sealants such as waterstops, gas-

kets, or compression seals; determination of joint movements, widths,

and depths; outline details of joints and sealants used in general struc-

tures, fluid containers, and pavements; methods and equipment for seal-

ant installation including preparatory work; performance of sealants;

and methods of repairing defective work or maintenance resealing. Fi-

nally, improvements needed to insure better joint sealing in the future

are indicated.

New developments in field-molded and preformed sealants and their

use are described together with means of measuring joint movements.

Appendix C provides a list of specifications and their sources.

Keywords: bridge decks: bridges (structures); buildings; compression seals; con-crete construction; concrete dams; concrete panels; concrete pavements; concretepipes; concrete slabs; concretes; construction joints; control joints; cracking (frac-turing); gaskets; isolation joints; joint fillers; joint scalers; joints (junctions); lin-ings; mastics; parting agents; precast concrete; reinforced concrete; repairs; sea-lers; specifications; tanks (containers); thermoplastic resins; thermosetting resins;walls.

CONTENTS

Chapter 1-General, p. 504R-21.1-Background

1.2-Purpose

1.3-Why joints are required1.4-Why sealing is needed

1.5-Joint design as part of overall structural design

1.6-Types of joints and their function1.7-Joint configurations

ACI Committee Reports, Guides, Standard Practices, and Commen-taries are intended for guidance in designing, planning. executing, orinspecting construction, and in preparing specifications. Reference

to these documents shall not be made in the Project Documents. Ifitems found in these documents are desired to be part of the ProjectDocuments, they should be incorporated directly into the Project

504

Chapter 2-How joint sealants function, p. 504R-42.1-Basic function of sealants2.2-Classification of sealants

2.3-Behavior of sealants in butt joints

2.4-Malfunction of sealants

2.5-Behavior of sealants in lap joints

2.6-Effect of temperature2.7-Shape factor in field-molded sealants2.8-Function of bond breakers and backup materials

2.9-Function of fillers in expansion joints

2.10-Function of primers

Chapter 3-Sealant materials, p. 504R-123.1-General

3.2-Required properties of joint sealants

3.3-Available materials

3.4-Field-molded sealants3.5-Preformed seals

Chapter 4-Joint movement and design,p. 504R-25

4.1-Discussion4.2-Determination of joint movements and locations

4.3-Selection of butt joint widths for field-molded sealants

4.4-Selection of butt joint shape for field-molded sealants4.5-Selection of size of compression seals for butt joints

4.6-Limitations on butt joint widths and movements for various

types of sealants4.7-Lap joint sealant thickness

4.8-Shape and size of rigid waterstops

4.9-Shape and size of flexible waterstops4.10-Shape and size of gaskets and miscellaneous seals

4.11-Measurement of joint movements

Chapter 5-Joint details, p. 504R-315.1-Introduction5.2-Structures

5.3-Slabs on grade, highway, and airports

5.4-Construction and installation considerations

R-1

504R-2 ACI COMMITTEE REPORT

Chapter 6-Installation of sealants, p. 504R-316.1-Introduction

6.2-Joint construction with sealing in mind

6.3-Preparation of joint surfaces

6.4-Inspection of readiness to seal

6.5-Priming, installation of backup materials and bond breakers

6.6-Installation of field-molded sealants, hot applied

6.7-Installation of field-molded sealants, cold applied

6.8-Installation of compression seals

6.9-Installation of preassembled devices

6.10-Installation of waterstops

6.11-Installation of gaskets

6.12-Installation of fillers

6.13-Neatness and cleanup

6.14-Safety precautions

Chapter 7-Performance, repair, andmaintenance of sealants, p. 504R-36

7.l-Poor performance

7.2-Repairs of concrete defects and replacement of sealants

7.3-Normal maintenance

CHAPTER l-GENERAL1.1-Background

This report is an update of the committee report originallyissued in 1970 and revised in 1977.1

Nearly every concrete structure has joints (or cracks) thatmust be sealed to insure its integrity and serviceability. It is acommon experience that satisfactory sealing is not alwaysachieved. The sealant used, or its poor installation, usuallyreceives the blame, whereas often there have been deficien-cies in the location or the design of the joint that would havemade it impossible for any sealant to have done a good job.

1.2-PurposeThe purpose of this guide is to show that by combining the

right type of sealant with proper joint design for a particularapplication and then carefully installing it, there is everyprospect of successfully sealing the joint and keeping itsealed. This report is a guide to what can be done rather thana standard practice, because in most instances there is morethan one choice available. Without specific knowledge of thestructure, its design, service use, environment, and eco-nomic constraints, it is impossible to prescribe a “best jointdesign” or a “best sealant”. The information contained inthis guide is, however, based on current practices and experi-ence judged sound by the committee and used by one or moreof the many reputable organizations consulted during itscompilation. It should therefore be useful in making an en-lightened choice of a suitable joint sealing system and to in-sure that it is then properly detailed, specified, installed, andmaintained.

No attempt has been made to reference the voluminous lit-erature except for those papers necessary to an understandingof the subject background. The present state of the art of jointsealing and identification of needed research may be found inthe proceedings of the 1st and 2nd World Congresses on JointSealing and Bearing Systems held in 1981 and 1986.2~3 Aglossary of terms that may not be generally familiar is pro-vided in the appendix.

Chapter 8-Sealing in the future and concludingremarks, p. 504R-37

8.l-What is now possible

8.2-Advancements still needed

Chapter 9-References, p. 504R-37

Appendix A-Layman’s glossary for jointsealant terms, p. 504R-38

Appendix B-Key to symbols used in figures,p. 504R-40

Appendix C-Sources of specifications, p. 504R-41

1.3-Why joints are requiredConcrete normally undergoes small changes in dimen-

sions as a result of exposure to the environment or by the im-position or maintenance of loads. The effect may be perma-nent contractions due to, for example: initial drying,shrinkage, and irreversible creep. Other effects are cyclicaland depend on service conditions such as environmental dif-ferences in humidity and temperature or the application ofloads and may result in either expansions or contractions. Inaddition, abnormal volume changes, usually permanent ex-pansions, may occur in the concrete due to sulfate attack, al-kali-aggregate reactions, and certain aggregates, and othercauses.

The results of these changes are movements, both perma-nent and transient, of the extremities of concrete structuralunits. If, for any reason, contraction movements are exces-sively restrained, cracking may occur within the unit. The re-straint of expansion movement may result in distortion andcracking within the unit or crushing of its end and the trans-mission of unanticipated forces to abutting units. In mostconcrete structures these effects are objectionable from astructural viewpoint. One of the means of minimizing them isto provide joints at which movement can be accommodatedwithout loss of integrity of the structure.

There may be other reasons for providing joints in concretestructures. In many buildings the concrete serves to supportor frame curtainwalls, cladding, doors, windows, partitions,mechanical and other services. To prevent development ofdistress in these sections it is often necessary for them tomove to a limited extent independently of overall expansions,contractions and deflections occurring in the concrete. Jointsmay also be required to facilitate construction without serv-ing any structural purpose.

1.4-Why sealing is neededThe introduction of joints creates openings which must

usually be sealed in order to prevent passage of gases, liquidsor other unwanted substances into or through the openings.

JOINT SEALANTS 504R-3

In buildings, to protect the occupants and the contents, it isimportant to prevent intrusion of wind and rain. In tanks,most canals, pipes and dams, joints must be sealed to preventthe contents from being lost.

Moreover, in most structures exposed to the weather theconcrete itself must be protected against the possibility ofdamage from freezing and thawing, wetting and drying,leaching or erosion caused by any concentrated or excessiveinflux of water at joints. Foreign solid matter, including ice,must be prevented from collecting in open joints; otherwise,the joints cannot close freely later. Should this happen, highstresses may be generated and damage to the concrete mayoccur.

In industrial floors the concrete at the edges of joints oftenneeds the protection of a filler or sealant between armoredfaces capable of preventing damage from impact of concen-trated loads such as steel-wheeled traffic.

In recent years, concern over the spread of flames, smokeand toxic fumes has made the fire resistance of joint sealingsystems a consideration, especially in high-rise buildings.

The specific function of sealants is to prevent the intrusionof liquids (sometimes under pressure), solids or gases, and toprotect the concrete against damage. In certain applicationssecondary functions are to improve thermal and acousticalinstallations, damp vibrations or prevent unwanted matterfrom collecting in crevices. Sealants must often performtheir prime function, while subject to repeated contractionsand expansions as the joint opens and closes and while ex-posed to heat, cold, moisture, sunlight, and sometimes, ag-gressive chemicals. As discussed in Chapters 2, 3 and 6,
these conditions impose special requirements on the proper-ties of the materials and the method of installation.
In most concrete structures all concrete-to-concrete joints(contraction, expansion and construction), and the peripheryof openings left for other purposes require sealing. One ex-ception is contraction joints (and cracks) that have very nar-row openings, for example, those in certain short plain slabor reinforced pavement designs. Other exceptions are certainconstruction joints, for example, monolithic joints not sub-ject to fluid pressure or joints between precast units used ei-ther internally or externally with intentional open drainingjoints.

1.5-Joint design as part of overall structuraldesign

In recent years it has become increasingly recognized thatthere is more to providing an effective seal at a joint thanmerely filling the “as constructed” gap with an imperviousmaterial. The functioning of the sealant, described in Chap-ter 2, depends as much on the movement to be accommo-dated at the joint and on the shape of the joint, as on the phys-ical properties of the sealant. Joint design, which broadlycovers the interrelationship of these factors, is discussed insome detail in Chapter 4 since it should be an important,
sometimes governing, consideration in the design of mostconcrete structures. It is considered beyond the scope of thisguide on sealing joints to venture into the whole field of vol-ume change in concrete and the structural considerations thatdetermine the location and movement of joints. It is, how-ever, pertinent to point out that many years of experience in
trying to keep joints sealed indicate that joint movementsmay vary widely from those postulated by theory alone.

There are probably as many “typical details” of joints inexistence as there are structures incorporating them. Facedwith the problem of illustrating, from the viewpoint of howthey can be sealed, the various types of joints and their uses,it appeared best to present them in schematic form in Chapter5 to bring out the principles involved for each of the threemajor groups of application to concrete:

1. Structures not under fluid pressure (most buildings,bridges, storage bins, retaining walls, etc.).

2. Containers subject to fluid pressure (dams, reservoirs,tanks, canal linings, pipe lines, etc.).

3. Pavements (highways and airfield).From both the structural and sealant viewpoint, irrespec-

tive of design detail and end use, all the joints may be classi-fied according to their principal function and configuration.

1.6-Types of joints and their function1.6.1 Contraction (control) joints-These are purposely

made planes of weakness designed to regulate cracking thatmight otherwise occur due to the unavoidable, often unpre-dictable, contraction of concrete structural units. They areappropriate only where the net result of the contraction andany subsequent expansion during service is such that theunits abutting are always shorter than at the time the concretewas placed. They are frequently used to divide large, rela-tively thin structuralunits, for example, pavements, floors,canal linings, retaining and other walls into smaller panels.Contraction joints in structures are often called control jointsbecause they are intended to control crack location.

Contraction joints may form a complete break, dividingthe original concrete unit into two or more units. Where thejoint is not wide, some continuity may be maintained by ag-gregate interlock. Where greater continuity is required with-out restricting freedom to open and close, dowels, and in cer-tain cases steps or keyways, may be used. Where restrictionof the joint opening is required for structural stability, appro-priate tie bars or continuation of the reinforcing steel acrossthe joint may be provided.

The necessary plane of weakness may be formed either bypartly or fully reducing the concrete cross section. This maybe done by installing thin metallic, plastic or wooden stripswhen the concrete is placed or by sawing the concrete soonafter it has hardened.

1.6.2 Expansion (isolation) joints-These are designed toprevent the crushing and distortion (including displacement,buckling and warping) of the abutting concrete structuralunits that might otherwise occur due to the compressiveforces that may be developed by expansion, applied loads ordifferential movements arising from the configuration of thestructure or its settlement. They are frequently used to isolatewalls from floors or roofs; columns from floors or cladding;pavement slabs and decks from bridge abutments or piers;and in other locations where restraint or transmission of sec-ondary forces is not desired. Many designers consider it goodpractice to place such joints where walls or slabs change di-rection as in L-, T-, Y- and U-shaped structures and wheredifferent cross sections develop. Expansion joints in struc-tures are often called isolation joints because they are


CHAPTER 2-HOW JOINT SEALANTSFUNCTION

2.1-Basic function of sealantsTo function properly, a sealant must deform in response to

opening or closing joint movements without any otherchange that would adversely affect its ability to maintain theseal. The sealant material behaves in both elastic and plasticmanners. The type and amount of each depends on: themovement and rate of movement occurring; installation andservice temperatures; and the physical properties of the seal-ant material concerned, which in service is either a solid or anextremely viscous liquid.

2.2-Classification of sealantsSealants may be classified into two main groups. These are

as follows:1. Field-molded sealants that are applied in liquid or semi:

liquid form, and are thus formed into the required shapewithin the mold provided at the joint opening.

2. Performed sealants that are functionally preshaped, usu-ally at the manufacturer’s plant, resulting in a minimum ofsite fabrication necessary for their installation.

intended to isolate structural units that behave in differentways.

Expansion joints are made by providing a space for the fullcross section between abutting structural units when the con-crete is placed through the use of filler strips of the requiredthickness, bulkheading or by leaving a gap when precastunits are positioned. Provision for continuity or for restrict-ing undesired lateral displacement may be made by incorpo-rating dowels, steps or keyways.

1.6.3 Construction joints-These are joints made at thesurfaces created before and after interruptions in the place-ment of concrete or through the positioning of precast units.Locations are usually predetermined by agreement betweenthe design professional and the contractor, so as to limit thework that can be done at one time to a convenient size withthe least impairment of the finished structure, though theymay also be necessitated by unforeseen interruptions in con-creting operations. Depending on the structural design theymay be required to function later as expansion or contractionjoints having the features already described, or they may berequired to be monolithic; that is, with the second placementsoundly bonded to the first to maintain complete structuralintegrity. Construction joints may run horizontally or ver-ticall y depending on the placing sequence required by the de-sign of the structure.

1.6.4 Combined and special purpose joints-Construc-tion joints (see Section 1.6.3) at which the concrete in thesecond placement is intentionally separated from that in thepreceding placement by a bond-breaking membrane, butwithout space to accommodate expansion of the abuttingunits, also function as contraction joints (see Section 1.6.1).Similarly, construction joints in which a filler displaced, or agap is otherwise formed by bulkheading or the positioning ofprecast units, function as expansion joints (see Section1.6.2). Conversely, expansion joints are often convenient forforming nonmonolithic construction joints. Expansion jointsautomatically function as contraction joints, though the con-verse is only true to an amount limited to any gap created byinitial shrinkage.

Hinge joints are joints that permit hinge action (rotation)but at which the separation of the abutting units is limited bytie bars or the continuation of reinforcing steel across joints.This term has wide usage in, but is not restricted to, pave-ments where longitudinal joints function in this manner toovercome warping effects while resisting deflections due towheel loads or settlement of the subgrade. In structures,hinge joints are often referred to as articulated joints.

Sliding joints may be required where one unit of a structuremust move in a plane at right angles to the plane of anotherunit, for example, in certain reservoirs where the walls arepermitted to move independently of the floor or roof slab.These joints are usually made with a bond-breaking materialsuch as a bituminous compound, paper or felt that also facili-tates sliding.

1.6.5 Cracks-Although joints are placed in concrete sothat cracks do not occur elsewhere, it is extremely difficult toprevent occasional cracks between joints. As far as sealing isconcerned, cracks mayirregular line and form,Section 7.2.2.

be regarded as contraction jointsTreatment of cracks is considered

ofin

1.7-Joint configurationsIn the schematic joint details for various types of concrete

structures shown in Chapter 5, two basic configurations oc-
cur from the standpoint of the functioning of the sealant.These are known as butt joints and lap joints.
In butt joints, the structural units being joined abut eachother and any movement is largely at right angles to the planof the joint. In lap joints, the units being joined override eachother and any relative movement is one of sliding. Butt joints,and these include most stepped joints, are by far the mostcommon. Lap joints may occur in certain sliding joints (seeSection 1.6.4), between precast units or panels in curtain-walls, and at the junctions of these and of cladding and glaz-ing with their concrete or other framing. As explained inChapter 2, the difference in the mode of the relative move-ment between structural units at butt joints and lap joints, inpart, controls the functioning of the sealant. In many of the-applications of concern to this guide, pure lap joints do notoccur, and the functioning of the lap joint is in practice a com-bination of butt and lap joint action.

From the viewpoint of the sealant, two sealing systemsshould be recognized. First, there are open surface joints, asin pavements and buildings in which the joint sealant is ex-posed to outside conditions on at least one face. Second,there are joints, as in containers, dams, and pipe lines, inwhich the primary line of defense against the passage ofwater is a sealant such as a waterstop or gasket buried deeperin the joint. The functioning and type of sealant material thatis suitable and the method of installation are affected by theseconsiderations.

In conclusion, two terms should be mentioned since theyare in wide, though imprecise use. Irrespective of their typeor configuration, joints are often spoken of as “workingjoints” where significant movement occurs and as “nonwork-ing joints” where movement does not occur or is negligible.


2.3-Behavior of sealants in butt jointsAs a sealed butt joint opens and closes, one of three func-

tional conditions of stress can exist. These are:1. The sealant is always in tension. Some waterstops [Fig. 1

(2A)] function to a large degree in this way though com-
pressive forces may be present at their sealing faces and an-chorage areas.
2. The sealant is always in compression. This principle, asillustrated in Fig. 1 (1A, B, C), is the one on which compres-
sion seals and gaskets are based.
3. The sealant is cyclically in tension or compression.Most field-molded and certain preformed sealants work inthis way. The behavior of a field-molded sealant is illustratedin Fig. 2 (1A, B , C) and an example of a preformed tension-
compression seal is shown in Fig. 9 (4).
A sealant that is always in tension presupposes that thesealant was installed when the joint was in its fully closedposition so that thereafter, as the joint opens and closes, thesealant is always extended. This is only possible with pre-formed sealants such as waterstops which are buried in thefreshly mixed concrete and have mechanical end anchors.Field-molded sealants cannot be used this way and the mag-nitude of the tension effects shown in Fig. 2 (1B) would likelylead to failure as the joint opened in service. Most sealingsystems used in open surface joints are therefore designed tofunction under either sealant in compression or a condition ofcyclically in compression and tension to take best advantageof the properties of the available sealant materials and permitease of installation.

2.4-Malfunctions of sealantsMalfunction of a sealant under conditions of stress consists

of a tensile failure within the sealant or its connection to thejoint face. These are known as cohesive and adhesivefailures, respectively.

In the case of preformed sealants that are intended to bealways in compression, malfunctioning usually results infailure to generate sufficient contact pressure with the jointfaces. This leads to the defects shown in Fig. 3 (1). This fig-ure also shows defects in water stops. Splits, punctures orleakage at the anchorage may also occur with strip (gland)seals.

Malfunctioning of a field-molded sealant, intended tofunction cyclically in tension or compression, may developwith repetitive cycles of stress reversal or under sustainedstress at constant deformation. The resulting failure will thenbe shown as one of the defects illustrated in Fig. 4.

Where secondary movements occur in either or both direc-tions at right angles to the main movement, including impactat joints under traffic, shear forces occur across the sealants.The depth (and width) of the sealant required to accommo-date the primary movement can more than provide any shearresistance required.

2.5 Behavior of sealants in lap jointsThe sealant as illustrated in Fig. 2 (2A, B , C) is always in

shear as the joint opens and closes. Tension and compressioneffects may, however, be added in the modified type of lapjoint used in many building applications.

2.6-Effect of temperatureChanges in temperature between that at installation and the

maximum and minimum experienced in service affect seal-ant behavior. This is explained by reference to Fig. 5.

The service range of temperature that affects the sealant isnot the same as the ambient air temperature range. It is theactual temperature of the units being joined by the sealantthat govern the magnitude of joint movements that must beaccommodated by the sealant. By absorption and transfer ofheat from the sun and loss due to radiation, etc., dependingon the location, exposure, and materials being joined, the dif-ference between service range of temperature and the rangeof ambient air temperature can be considerable.

For the purpose of this guide, the service range or tem-peratures has been assumed to vary from -20 to + 130 F (-29to + 54 C) for a total range of 150 F (83C). In very hot or coldclimates or where the joint is between concrete and anothermaterial that absorbs or loses heat more readily than con-crete, the maximum and minimum values may be greater.This is particularly true in building walls, roofs and in pave-ments. On the other hand, inside a temperature-controlledbuilding or in structures below ground the range of servicetemperatures can be quite small. This applies also to con-tainers below water line. However, where part of a containeris permanently out of the water, or is exposed by frequentdewatering, the effects of a wider range of temperatures mustbe taken into account.

The rate of movement due to temperature change for shortperiods (ie: an hr, a day) is quite as important as the totalmovement over a year. Sealants generally perform better, thatis, respond to and follow joint opening and closing when thismovement occurs at a slow and uniform rate. Unfortunately,joints in structures rarely behave this way; where restraint ispresent, sufficient force to cause movement must be gener-ated before any movement occurs. When movement is inhib-ited due to frictional forces, it is likely to occur with a suddenjerk that might rupture a brittle sealant. Flexibility in the seal-ant over a wide range of temperatures is therefore important,particularly at low temperatures where undue hardening orloss of elasticity occurs with many materials that would oth-erwise be suitable as sealants. Generally all materials per-form better at higher temperatures, though with certain ther-moplastics softening may lead to problems of sag, flow andindentation.

Furthermore, in structures having a considerable numberof similar joints in series, for example, retaining walls, canallinings and pavements, it might be expected that an equalshare of the total movement might take place at each joint.However, one joint in the series may initially take moremovement than others and therefore the sealant should beable to handle the worst combination.

These considerations are discussed in detail in Chapter 4.

2.7-Shape factor in field-molded sealantsField-molded sealants should be 100 percent solids (or

semi-solids) at service temperatures and as shown in Fig. 2,they alter their shape but not their volume as the joint opensand closes. These strains in the sealant and hence the ad-hesive and cohesive stresses developed are a critical functionof the shape of the sealant. For a given sealant then, its elastic


02. WATERSTOPS

These seals are normally in tension during their working range.(A) WORKING JOINT

AS INSTALLEDJOINT OPEN (B) NONWORKINGTO WATER JOINT

1 1Labyrinth ribs to anchorand form long path seal;

orDumbbell end to anchor -and form cork-in-a-bottle

--Center bulb or fold facilitatesnormal joint movements

seal.

(ii) Material (A) (i)requirements

(ii)

Flexible materials with properties similar to (B) (i)aabove

Rigid flat plates also used where movement iscomparitively small (otherwise sliding end orfold needed to permit movement). Must resistdeformation due to fluid pressure. High dur-ability since replacement not practical

(ii)

(iii) Deficiencies lead to failures shown in Fig. 3 0

Asphalt coating may be __-A

needed to assist seal andprevent bond at one end.

Rigid noncorrosive materialssuitable, some ductility andflexibility may be desirable

Flexible materials may beconvenient but not essential

Fig. 1 -How preformed compression seals, gaskets, and waterstops work

The behavior of these preformed sealants depends on a combina-tion of their elastic and plastic properties acting under sustainedcompression.

01 COMPRESSION SEALSAND GASKETS

(A) AS INSTALLED (B) JOINT OPEN (C) JOINT CLOSED

(i) Sealant is: . . . . . . . . . . . . . . . . Always in compression Always in compressionand

Sealant must: . . . . . . . . . . . . . . Change its shape as its width changes (Note 1)

- O u t w a r d pressure on faces(ii) Material requirements for good performance: maintains the sealing action

(A) (B) (C)(a) Good contact (bond (d) Rubber-like properties (e) Low compression set

not needed) (f) Webs should not weld(b) Correct size (g) Should not extrude(c) Suitable configuration from the joint

Also required (see Section 3.1) (1) Impermeability (3) Recovery (7) Nonembrittlement (8) Not deteriorate

(iii) Deficiencies in (b) (d) (e) (f) predisposes to loss of contact pressure. See Fig. 3 @ for consequences

Note 1Compression seals in working joints require to be compartmentalized or foldableto meet this criterion, gaskets in nonworking joints may not.


O1 IN BUTT JOINTS

(A) AS INSTALLED

(i) Sealant is: . . . . . . . . . .and

(B) JOINT OPEN (C) JOINT CLOSED

Sometimes in tension and sometimes in compression

Sealant should: . . . . . . . . Change its shape without changing its volume

Cohesive (tensile) stress in sealant 1 1 1Adhesive (bond) stress at interfaceJ 1 1Peeling stress at edge A 1Tensile stress in face material-

(ii) Material requirements for good performance:

(A) (B)

Compressive stress insealant

(C)(a) Ease of installation(b) Good bond to faces(c) Homogeneity(d) Low shrinkage

(e) High ultimate strengthin rubberlike materials

(f) Low elastic modulusin rubberlike materials

(g) Resistance to flow andstress relaxation

(g)

(h)

Resistance to flow andstress relaxationLow compression set

Also required (see Section 3.1) (1) Impermeability (3) Recovery (6) Resist flow (7) Not harden(8) Not deteriorate

(iii) Deficiencies in (b) (c) (f) predispose towards adhesion failure(c) (d) (e) predispose towards cohesive failure See Fig. 4 for(h) (3) (6) predispose towards permanent deformation consequences(g) (3) (6) predispose towards flow and stress relaxation(a) (7) (8) accelerate failures due to above causes

O2 IN LAP JOINTS

(A) AS INSTALLED (B) JOINT OPEN (C) JOINT CLOSED

(i)

(ii)

Sealant is: . . . . . . . . . Always in shear(Note ‘) Always in shear (Note 1)

Material Requirements: These are generally similar to those above for butt joints. Same materials used (seeChapter 3) with thickness of sealant (distance between the overlapping faces) equal to 2 times the deformationof sealant in shear (which is the joint movement) depending on installation temperature (See Fig. 5).

The behavior of field-molded sealants in service depends upon a combination of their elastic and plastic properties. Elas-tomeric sealants should behave largely elastically to regain after deformation their original width and shape, that is fullstrain recovery (no permanent set) is desirable. However due to plastic behavior some set, flow, and stress relaxation occurs.The extent of its effect depends on the properties of the particular materials used and conditions such as temperature,repetition and rapidity of cycles of stress reversal and duration of deformation at constant strain. Largely plastic behavior,that is, returns to original shape by flow, is only acceptable for sealants used in joints with small and relatively slowmovements.

Note 1 : If, as lap joint opens or closes, units move closer together or farther apart in plane at right angles tomain movement then compression or tension of the sealant will also occur. This combination ofmovements is common in many applications to buildings (see Fig. 8). Where both types of movement
are expected, the combined movement should be considered to determine the thickness of sealant.required in the joint design.
Fig. 2-How field-molded sealants work

504R-8

02

WaterstopDefects :

ImprovePerformance by:

@J Contamination of surface preventsbond to concrete

Complete break dueto poor or no splice

@ Over extended at joint - may split OB Honeycomb concrete areas permit leakage

00A i

(ii)

Selecting size suitable for jointmovementAvoid rigid anchored flat types

@ @ @ (i) Proper installation and concretingpractices

(ii) Since replacement is usually notpossible try grouting or secondarysealant as remedial measure

Fig. 3 -Defects in preformed sealants

@ CompressionSeal Defects:

ImprovePerformance by:

WATER AND DEBRISPENETRATES

O A Seal too small (@ Seal lost ability to recover

Seal is out of compression incold weather

UNFOLDS AND STANDS TRAFFICOUT WHEN JOINT OPENS TEARS SEAL

CONCRETE SPALLS

FILLER PUSHES UP

OC Folded or twisted at (@ Over compressed and extrudedinstallation at expansion joints

Failure noticed in hot weather

@(i) Use wider seal(ii) Form or saw cut joint with shoulder

@ Install seal straight, lubricate joint faces andalso to prevent breaks avoid stretching

support seal(iii) Avoid stretching during installation OD

@ Use seal with better properties to providelow temperature recovery and avoid (ii)compression set (iii)

Usually occurs in pavements with mixedsystem of expansion-contraction joints,avoid this designForm or saw groove widerLeave air gap on top of filler


0 DefectsGainlyAssociated withElasticBehavior

ImprovePerformanceby -

0 DefectsMainlyAssociated withNon ElasticBehavior

ImprovePerformanceby -

O3 DefectsMainlyAssociated withFlow and StressRelaxation

WATER AND DEBRIS CAN

/NOW PENETRATE

@Too deep compared to @ Overextended; may lead 0 Peeling at points ofwidth. Bonded at bottom to fatigue failure stress concentration

such as edges

WATER AND DEBRIS CAN NOW PENETRATE

(@ Adhesion (bond to @ Cohesion (internal @ Impact spall if concretejoint face) failure rupture) failure is weak

(i) m -Better shape factorm

(ii) Use of bond breaker and/or H

to reduce strains to those backup materialssealant can withstand

(iii) Closer joint spacings to reduceindividual movements

(iv) Select better sealant

(v) a Clean faces and prime (vi) @ S aw rather than formarmor edges

(vii) Improvements (i) to extend life of sealant. Eventual failure must be expecteddue to combinations of , viscous flow, stress relaxation, permanent set etc.,with repetitive cycles of stress reversals (Seem below) _

Unsightly elephant ears rundown vertical joints. Trackedby traffic -

Also staining anddamage due toexudation of volatiles

4I-w

@ Debris inclusion can lead to spalling, loss ofsealant material, change in properties

0

@ Extrusion or blistering @ Extrusion ofof sealant filler

@ a n d OI

(i) Select sealant that will resist intrusion(ii) Routine cleanup of debris(iii) Indentation by spiked heels, etc.

requires (i)

(i)(ii)(iii)

(iv)

(v)

Use better shape factorCloser joint spacingsAvoid mixed expansion contraction jointpavement designs so as to equalize movementAvoid trapping air and moisture atinstallationSelect better sealant and more compressiblefiller and do not overfill joints or set filler toohigh

(i)

0 (i) sags or (ii) humpsafter extension or (iii) necks after compression as direction of movementreverses

Little improvement possible if ‘best’ sealant is being used. Support may help somewhat.

Fig. 4 -Defects in field-molded sealants


Hypothetical cases showing the effect of installation temperatures in relation to the range of service temperatures,assuming the joint width at mean temperature equals the total joint movement between fully open and fully closedpositions. (for simplicity of analysis only temperature effects shown)

O1 SEALANT INSTALLED AT MEAN TEMPERATURE

(A) INSTALLATION AT MEAN (B) JOINT OPEN ATTEMPERATURES 55 F (13 C) -20 F (-29 C)

&I I+1’12 w

*I

Sealant must extend or compress by 50 percent in service.

@ SEALANT INSTALLED AT LOW TEMPERATURE

(A) INSTALLATION AT MINIMUM (B) JOINT HALF CLOSEDTEMPERATURES -20 F (-29 C) AT 55 F (13 C)

(C) JOINT CLOSED AT130 F (54 C)

__>I1/2 wI<__

(C) JOINT CLOSED AT130 F (54 C)

Sealant must compress by 66.66 percent in service.Probability of Permanent Deformation or Extrusion. 50 percent more sealant needed.

@ SEALANT INSTALLED AT HIGH TEMPERATURE

(A) INSTALLATION AT MAXIMUM (B) JOINT HALF OPEN (C) JOINT OPEN ATTEMPERATURE 130 F (54 C) AT 55 F (13 C) -20 F (-29 C)

L2w,I L 3w ,I

Sealant must extend by 200 percent in service.Adhesion, cohesion, or peeling failure certain.

CONCLUSION: The closer the installation temperature is to the mean annual temperature the less will be the strainin the sealant in service and the better it will perform in butt joints. Taking into account practical considerations(see Chapter 4 and 6) an installation temperature range of from 40 to 90 F (4 to 32 C) is acceptable for mostapplications.

Note: (i) Though not illustrated similar considerations govern the selection of the size of compression seals(see Section 4.5). Failure in case (3) above would however be by loss of contact with joint faces when

(ii)

seal passes out of compression.

Maximum deformation of a sealant in lap joints is also governed by installation temperature. Sealantthickness not less than joint movement acceptable for all temperatures (see Fig, 2.2) may be reducedto % provided installation temperature is between 40 and 90 F (4 and 32 C) (movement approximatelyM each way).

Fig. 5-Effect of temperature on field-molded sealants


Cases showing the effect of shape on the maximum strains ‘S’ which occur on the parabolic exposed surface ofelastomeric sealants. Sealant assumed to be installed at mean joint width so that ‘/2 change of width of sealant willbe extension and % compression.

BUTT JOINTS

O1. JOINT DEPTH TO WIDTH RATIO 2: 1

(A) AS INSTALLEDMEAN WIDTH

l+w+l

Units of SealantRequired: 4

(B) JOINT OPEN (C) JOINT CLOSED

S=0

O2 JOINT DEPTH TO WIDTH RATIO 1: 1

Wv


*

d=w

s^=o^

O3 JOINT DEPTH TO WIDTH RATIO 1: 2


S = 250%

S=32% S=20%

CONCLUSION: Increasing the width and reducing the depth generally reduces strains and hence improves per-formance of field molded sealants. At the same time less sealant is required. Shape Factor is less importantin mastic sealants since plastic not elastic behavior dominates.

@ PURPOSE OF BOND BREAKER AND BACK UP: In joints open on one face only the back face of the sealantmust not adhere to the bottom of the sealant reservoir so that the sealant is free to assume the desired shape.See (A) below. Control of depth of sealant is achieved as shown in (B) where the joint is formed or sawninitially deeper than the required depth to width ratio. (Bi) and (Bii) present cases as to desirable shape ofbackup.

(A) FUNCTION OF (B) FUNCTION OF (Bi) CURRENT PRACTICEBOND BREAKER BACKUP MATERIAL

BACKUP LIMITSSEALANT DEPTHAND CONTROLSSHAPE

-SHAPE ANDGREATER BONDFACE ASSUMEDTO REDUCEADHESIVESTRESSES

SEALANT CAN NOWFREELY ASSUMEPARABOLIC SURFACEON THE BOTTOM ASWELL AS TOP

ADDITIONAL BENEFITIS TO SUPPORT SEALANTAND PREVENT SAG

PREFORMED ROUND RODOR TUBE BACKUP

(Bii) While Detail (Bi) is widely accepted andused, some recent research suggests (B)may be better since, if backup materialpresents flat face to sealant, peeling stressesat corners are reduced.

Fig. 6-Shape factor and strains in field-molded sealants


CHAPTER 3-SEALANT MATERIALS3.1-General

This chapter deals with the functional properties of sealingand accessory materials. Because of their physical limita-tions many materials only perform well in joints of small ini-tial width and subsequent movement. The configuration ofthe joint, the process by which it is constructed (formed) andaccess for installation of the sealant also impose restrictionson the types of material that may be suitable for a particularapplication.

In service, environmental conditions often dictate addi-tional performance requirements beyond those needed to ac-commodate movements alone.

Selection of the most appropriate materials for a particularapplication is not a simple matter in view of all the variablesinvolved. Once an understanding is gained of the basic prop-erties of materials required, then available materials can beclassified and related to their suitability in various types ofjoints. This information is conveniently displayed in a seriesof tables and is cross referenced in later figures which illus-trate the details of various joint applications in concretestructures.

extensibility is a function of the shape of the mold in which itwas installed as well as the physical properties of the mate-rial. A mathematical analysis of sealant deformation wasmade by Tons ,4 whose laboratory measurements showed thatthe exposed surfaces of an elastically deformed sealant as-sume a parabolic shape until close to rupture. Tons concludedthat total extensibility is increased directly with width and in-versely with the depth of the sealant in the joint. From Tons’sdata and that of Schutz,5 Fig. 6 (lA, B, C, 2A, B, C, 3A, B,C) has been prepared to illustrate the critical importance (andeconomy) of using a good shape factor especially with ther-mosetting, chemically curing field-molded sealants. Shapefactor pertains to the ratio between the width of a sealant andits thickness (depth) determined by experience and lab tests.

It must be remembered that while selections of shape fac-tor are essentially based on accommodating cohesive stressesin the sealant, at the time of placement an adequate area mustbe provided at the joint face to accommodate adhesive (bond)stresses. For this reason, experience has indicated a prefer-ence in certain applications, such as in concrete pavements,for a minimum 3:2 (depth to width) shape factor rather thanthe theoretically more desirable ratio (shown in Fig. 6) of 1:1or l:2 in order to achieve a better service performance.

2.8-Function of bond breakers and backupmaterials

Bond breakers and backup materials are used, as illus-trated in Fig. 6 (4A, B), to achieve the desired shape factor infield-molded sealants. The principal material requirement fora bond breaker is that it should not adhere to the sealant.Important secondary benefits of a backup material are that itsupports the sealant and helps resist indentation, sag and al-lows a sealant to take advantage of maximum extension.These may often be important considerations when selectingthe appropriate type and shape of preformed backup mate-rial. The backup material must also be compressible withoutextruding the sealant and must recover to maintain contactwith the joint faces when the joint is open.

2.9-Function of fillers in expansion jointsFillers are used in expansion joints to assist in making the

joint and to provide room for the inward movement of theabutting concrete units as they expand. Additionally theymay be required to provide support for the sealant or limit itsdepth in the same manner that backup materials do. Theserequirements are usually met by preformed materials that canbe compressed without significant extrusion and preferablyrecover their original width when compression ceases. Stiff-ness to maintain alignment during concrete placement andresistance to deterioration due to moisture and other serviceconditions are also usually required.

2.10-Function of primersLaboratory and field experience indicates that priming

joint faces is essential for certain field-molded sealants andcan generally improve their bond strength and hence exten-sibility, especially at low temperatures. Depending on thesealant and condition of the sealant-to-joint interface, the im-provement in adhesion may result from one or more of thefollowing: sealing and penetration of the concrete pores, pre-coating of the concrete pores, precoating of the dust parti-

cles, reduction in bubble formation, and reduction in the ab-sorption of oils by the concrete.

This chapter discusses field molded sealing materials usedwhere one surface of the finished joint is open to permit thesealing operation. Sealants used for these applications arelisted in Table 1. The joint design for an expansion (isolation)
joint may consist of a filler strip below the area where thesealant will be placed, bond breaker material to separate thesealant from an adhering substrate, and backup materials tosupport the material from sagging. These appurtenant mate-rials are listed in Table 2. Preformed materials used in joints open on at least one surface, materials used as water stops andgaskets are listed in Table 3.
Table 4 shows some of the current uses to which the vari-
ous sealants are put, and consideration of storage and han-dling for installation. In cross-referencing types of materialsthe Roman numeral system is used in Tables 1 and 4 and inFig. 7 to 12. Individual field-molded sealant materials are let- tered A, B , C, and so on, as in Table 1. Individual preformedsealant materials are identified by numbers given in Table 3.
Appendix C lists various specifications and sources of cur-
rent specifications.
3.2-Required properties of joint sealantsFor satisfactory performance a sealant must:1. Be an impermeable material.2. Deform to accommodate the movement and rate of

movement occurring at the joint.3. Sufficiently retain its original properties and shape if

subjected to cyclical deformations.4. Adhere to concrete. This means that for all sealants; ex-

cept those preformed sealants that exert a force against theconcrete surfaces or are mechanically interlocked with an an-chorage, the sealant must bond to the concrete surfacesandnot fail in adhesion (lose its bond to the concrete) nor peelat corners or other local areas of high stress (see Fig. 4).


TABLE 1-MATERIALS USED FOR JOINT SEALING

GROUP FIELD-MOLDED I PREFORMED

TYPE I MASTIC THERMOPLASTICS I THERMOSETTING COMPRESSIONII HOT APPLIED 1 III COLD APPLIED 1 IV CHEMICALLY CURING VSOLVENT RELEASE V I SEAL

Composition (A) Drying Oi ls(B) Non-drying Oi ls(C) Low Melt. Point

Asphalt(D) Polybutenes

(E) Polyisobutylenesor combination of D & E

All used with fillers,

all contain 100% solids,except D & E which maycontain solvent.

Colours (A) (B) Varied(C) Black only

(D) (E) LImIted

(F) Asphalts

(G) Rubber Asphalts(H) Pitches(I) Coal Tars

(J) Rubber Coal Tars

All contain 100%solids(W) Hot applied PVC

coal tar

Black only

(K) Rubber Asphalts(L) VInyIs(M) Acrylics(K) Contalns 70.80%

sol ids(L) (M) Contain 75.

90% solidsAll contain solvent,(K) may be an emulsion(60-70% solids).

(X) ModifiedButyl Rubber

(K) Black only(L) (M) Varied

(N) Polysulfide(0) Polysulfide Coal Tar(P) Polyurethane

(0) Polyurethane Coal Tar(R) Silicones

(S) Epoxy(N),(R) contain 95-100% sollds(O),(Q),(S) contain 90-100%

solids

(P) contains 75-100% solids(N),(P),(R) may be either one

or two component system

(O),(Q), (S) two componentsystem.

(T) Neoprene

(U) ButadleneStyrene

(V) Chlorosul-

fonatedPolyethylene

(T) (V) contain80-90% solids

(U) contains85-90% solids

(R) Silicones

Neoprenerubber

(N) (R) (S) Varied

(0) (PI LImited

(Q) Black only

(T) LImited(V) Varied

Black. Exposedsurfaces may be

treated to givevaried colours

Setting

OrCuring

Release of solvent . . . . .

Aging andWeathering

Resistance

Increase in

Hardness inRelation to

(1) Age

Low

High

Moderate

(W) High resistanceto weather

High to Moderate(W) No hardness

Moderate

H igh

High H igh High

(S)

(N) (O) (P) (Q) (R) ModerateH’gh 1 High; Low

or (2) Low temp High High to Moderate(W) No hardness

High (S)

(N) (0) (PI (Q) (R) L o w

H igh Low

Recovery

Resistance toWear

Resistance to

Identat ionand Intrusion of

Solids

Low

Low

Low

Moderate

(W) High

Moderate

Low at Hightemperatures(W) High

Low

Moderate

Low at hightemperatures

(N) (0) Moderate Low High(P) (Q) (R) High(S) Low

(P) (0) (R) (S) ~~~,,,,,(N) (0)

High

High

1 Moderate

Low High

ShrInkage afterInstallation

H igh

IVaries High Low

IHigh None

(W) None

Resistance toChemicals

High except tosolvents and fuels

(F) (G) High exceptto solvents and fuels(H) (I) (J) High a n dfuel resistant(W) High

(K) High except tosolvents and fuels

(L) (M) High exceptto alkalis and

oxldlzlng acids

(N) (P) Low to solventsfuels, oxidizingacids

(O) (Q) Low to solvents

but moderate fuel

resistance

(R) Low to alkalis

(S) High

Low to solvents,fuels and oxldlzlng

acids

High

Modulus at

100%Elongation

Not applicable Low Low(R) (0) (P) (Q) L o w(R) High and Low

(S) Not applicableModerate

AllowableExtension andCompression

+3%+ 5%-(W) +25% extension

&7% _+25% except (S) less

+ 100% some (R)5 0 %

27%

Must be compressedat all times to 45-

85% of its originalwidth

OtherProperties

(A) (B) (D) (E)Non-staining(D) (E) Pick up dirt,use in concealedlocation only.

Due to softening in hot (K) Usable i n (N) (P) (R) (S) (U) (V) Non-

weather usable only in inclined joints Non-stalning staining

horizontal joints (V) Good vapour

(W) No flow at elevated and dust sealer

temperatures

Unit first cost (A) (B) (C) very low

(D) (E) Low(F) (G) (H) (I)(J) Very low(W) Medium

(K) Very low

(L) Low

(Ml High

(0) (Q) (R) High

(N) (P) (R) (S)Very High

(T) (U) (V) L o w (3) High

5. Not internally rupture or pull apart within itself (that is,fail in cohesion) (see Fig. 4).

6. Resist flow due to gravity (or fluid pressure) or un-acceptable softening at higher service temperatures.

7. Not harden or become unacceptably brittle at lowerservice temperatures.

8. Not be adversely affected by aging, weathering or otherservice factors for a reasonable service life under the range oftemperatures and other environmental conditions that occur(see Fig. 7 to 12).

In addition, depending on the specific service conditions,the sealant may be required to resist one or more of the fol-


TABLE 2-PREFORMED MATERIALS USED FOR FILLERS AND AS BACKUP WITHFIELD MOLDED SEALANTS

COMPOSITION AND TYPE USES AND GOVERNING PROPERTIES I INSTALLATION

(1) Natural rubber(a) Sponge(b) Solid

Expansion joint filler. Readilycompressible and good recovery.Closed cell. Non-absorptive. Solidrubber may function as filler butprimarily intend as gasket, seeTable 3(8).

High pliability may cause instal-lation problems. Weight of plasticconcrete may precompress it. Inconstruction joints attach to firstplacement with adhesive.

(12) Neoprene or Butyl Sponge Backup Compressed into joint with handtubes Where resilience required in tools.

large joints. Check for com-patibility with sealant as tostaining.

1. I(13) Neoprene or Butyl Sponge Backup

rods Used in narrower joints, e.g. con-traction joints in canal linings andcoverslabs and pavements. Checkfor compatibility with sealant as

I to staining.I

(14) Expanded polyethylene poly-urethane and polyvinyl chloridepolypropylene flexible foams

(a) Expansion joint fillers. Readilycompressible, good recovery,Non-absorptive.

Compressed intotools or roller.

Must be rigidly supported for fulllength during concreting.

I (b) Backup Compressed into joint with handCompatible with most sealants tools.

(15) Expanded polyethylene, poly- Expansion joint filler. Useful tourethane and polystyrene form a gap but after significantrigid foams compression will not recover.

Support in place during concreting.In construction joints attach tofirst placement. Sometimes removedafter concreting where nolonger needed.

(16) Bituminous or ResinImpregnated corkboard

Expansion joint filler. Readilycompressible and resilient. Not

compatible and must be isolated

Support in place during concreting,or attach to preceding placement.Boards easily damaged by careless

(17) Bentonite or DehydratedCork

Filler with self-sealing properties.Absorption of water after instal-lation causes material to swell.Cork can be compressed. Bentoniteincompressible.

Cork available in moisture-proofliners that require removal beforeinstallation. Bentonite in powderform, loose or within cardboardliners.

(18) Wood Cedar, Redwood, Expansion joint filler, has been Rigid and easily held in alignmentPine, Chipboard, Untreated widely used in the past. Swells during concreting.Fibreboard when water is absorbed. Not as

compressible as other fillers andless recovery. Natural woodsshould be knot-free.

(19) Bituminous impregnatedfiberboard

Expansion joint filler. Widelyused. Resilient cane fibre used.Has moderate recovery after com-pression. Should not be com-

I pressed more than 50 percent or bitumenextruded which may damage sealant.

Reasonably rigid to hold alignmentduring concreting or placed againstpreceding placement.

(20) Metal or Plastic

(21) Glass Fibre, Mineral wool

(a) Expansion joint filler. Hollow com-pressible thin gauge box. Usedonly in special applications.

(b) Backup, Foil, inert to sealants,but shape irregular.

(a) Expansion joint filler. Made inboard form by impregnating withbitumen or resins. Easily com-pressed.

(b) Backup. Inert without impreg-nation so as not to damagesealant.

Installed as for wood or fibreboardmaterials.

Crumple and place in joint.

Installed as for wood or fibreboardmaterials.

In mat form or packedmaterial or yarn.

loose

(22) Oakum, Jute, Manila yarnand rope, and Piping Uphols-

tery cord

The traditional material forpacking joints before installingsealant. Where used as backupshould be untreated with oils, etc.

(23) Portland CementGrout or Mortar

Packed in joint to required depth

Used at joints in precast units andpipes to fill the remaining gapwhen no movement is expectedand sometimes behind waterstops.

Bed (mortar)Inject (grout)


TABLE 3-PREFORMED MATERIALS USED FOR COMPRESSION SEALS, STRIPSEALS, TENSION-COMPRESSED SEALS, WATERSTOPS, GASKETS, AND

MISCELLANEOUS SEALING PURPOSES

COMPOSITION AND TYPE PROPERTIES SIGNIFICANT AVAILABLE IN USESTO APPLICATION

(1) Butyl - Conventional I High resistance to water, vapour 1 Beads, Rods, tubes, flat 1 Waterstops, Combined crackRubber Cured and weathering. Low permanent

set and modulus of elasticity form-ulations possible, giving high co-hesion and recovery. Tough.Colour - Black, can be painted.

sheets, tapes and purpose-made shapes.

inducer and seal, Pressuresensitive dust and water seal-ing tapes for glazing andcurtain walls.

(2) Butyl - Raw, Polymer High resistance to water, vapour Beads, tapes, gaskets, Glazing seals, lap seams inmodified with resins and and weathering. Good adhesion to grommets. metal cladding. Curtain wallplasticisers metals, glass, plastics. Moldable panels.

into place but resists displacement,tough and cohesive. Colour -Black, can be painted.

I I(3) Neoprene - Conventional High resistance to oil, water, Beads, rods, tubes, flat-

Rubber cured vapour and weathering. Low sheets, tapes, purpose-madepermanent set. Colour - shapes. Either solid or openbasically black but other surface or closed cell sponges.colours can be incorporated.

Waterstops, Glazing seals,Insulation and Isolation of servicelines. Tension-Compression seals.Compression Seals. Gaskets, StripGland Seals.

(4) PVC High water, vapour, but only Beads, rods, tubes, flatPolyvinylchloride moderate chemical resistance. sheets, tapes, gaskets,Thermoplastic, Low permanent set and modulus of purpose-made shapesExtrusions or Moldings elasticity formulations possible,

giving high cohesion and recovery.Tough. Can be softened by heatingfor splicing. Colour - Pigmentedblack, brown, green, etc.

(5) Polyisobutylene High water, vapour resistance. Beads, tapes, grommets,Non curing High flexibility at low temperature gaskets.

Flows under pressure, surfacepressure sensitive, high adhesion,Sometimes used with butyl com-pounds to control degree of cure.Colour - Black, grey, white

I I I

Waterstops, Gaskets, Com-bined crack inducer and seal.

Gaskets, Glazing Seals,Curtain wall panels,Acoustical partitions.

Waterstops, Gaskets for pipesInsulation and Isolation ofService Lines

(6)a S B R (StyreneButadiene Rubber)

High water resistance, NBR hashigh oil resistance.

Beads, rods, flat sheetstapes, gaskets, grommets,purpose-made shapes.Either solid or cellular(6)b N B R (Nitrile

Butadiene Rubber)Polyisoprene - poly-diene - ConventionalRubber cure

sponges.

Gaskets, Compression Seals .Rods flat sheets (strips)open cell spongesEVA closed cell

(7) a Polyurethane, Foamimpregnated with poly-butylene

(7) b Ethylene Vinyl Acetate

Low recovery at low temperature,can be installed in damp joints,Colour - Variety

Waterstops, Gasket for pipes.Strip-Gland SealsTension-CompressionCompression Seals

Purpose-made shapes.High water resistance but deter-iorates when exposed to air andsun. Low resistance to oils andsolvents. Now largely supersededby synthetic materials, Colour black

For waterstops:(a) Ductile and Flexible, but work

hardens under flexing andfractures.

(b) Rigid must be V or U corr-gated to accommodate anymovement and anchored.

(c) Deforms readily but inelastic

(8) a Natural Rubber - cured(vulcanized)

(8) b EPDM(8) c Silicones

(9) Metals(a) Copper(b) Steel (stainless)(c) Lead(d) Bronze

I-(a) (b) Waterstops(c) Protection for joint edges in

floors.(d) Panel dividers in floor toppings

Flat and preshaped strips,Lead also molten or yarn.

to deformation under movement. -As alternative to hot or coldapplied Rubber asphalts(IIG IIK), Gasket forpipes.

Beads, rods, flatsheets(strips)(IIG IIIK),Gasket for

I(10) Rubber Asphalts Natural Rubber 8, Butyl 1, or

Neoprene 3 digested in asphalt.High viscosity, some elasticity.Moldable into place.

I .

g*$,s I/

1

TABLE 4-USES OF FIELD MOLDED AND PREFORMED SEALANTS*

TYPE OF APPLICATION FIELD-MOLDED PREFORMED

THERMOPLASTIC THERMOSETTING . VI COMPRESSIONI MASTICS II HOT APPLIED 1 Ill COLD APPLIED IV CHEMICAL CURE1 V SOLVENT RELEASE STRIP SEAL VII WATERSTOPS I.A B D EA B D EA B D E

L MM

Caulking and GlazingPrecast PanelsWalls(Verticai joints)Roof Deck (Horiz. joints) F G WGeneral FloorsIndustrial Floors G H W KFloors with oil & solvents H I J WServices 3 6Bridges G W 378

Canal Linings C G W K 0 R+ 38 1 4Precast Pipes 1 3 4 5 6 8 10Tanks & Monolithic Pipe 134689a9b 10Swimming PoolsDamsWalls & floors with water outside 3 Note 2

1 N P R SN P R

~ N P RN O P Q R

NOPQRN P Q R

NOQRS

IN O Q R

T U VT VT VT V

3838378378383838

1 21 2 101010149d1 3 9 c

111 0 3Note2

Structures notunder fluidpressure: e.g.,buildings, bridgesstorage bins,retaining walls

Note 3

Containerssubject tofluid pressure:e.g., water containingor excludingstructuresNote 3

Pavements WalkwaysHighwayAirportAreas with fuel spillage

Grouting nonworking cracks I I I K I S I I I I I 23

Suitable inabove applicationswhere jointmovement is:Note 4

None or very small Contraction A B C D E F G H I J K L M N O P Q R S T U V 38 134689a9b 1 3 4 5 6 7 8 1 2 9c 9dsmall

1

> joints F G H I J K L M N O P Q R T U V 38 134689a9b 7large Expansion N O P Q R 38 3 4very large joints 38 3 Note 2

Storage Life: Limited (1) Over 1 year (0)Emulsions are damaged by freezing

A B C D E(o) F G H I J(o) I K L M(o) N O P Q R S ( l ) T(o) U V(1) 1 -9(o) 1 -8(o)I I I I 3 7(c) 8(c) 1 -11(o)

Installation: Knife or Trowel (k)Insert (i), Heat 81 pour (h)Mix if two component (ml, Note 5Hand Gun (g), Pressure Gun (p)Preposition (pp)

A B(k)(g)(p) F G H I J (h) K L(g)(k)(p) N O P Q R S T U V(k)(g)(p) 3(i) 8(i) 1 - 9(pp)C(k)(g) (WI (h)

1 - 8(pp)M(g) preheat

1 2 3 4 9d lO(pp)(m)(k)(g)(p) 9c(i) (h)

D E(g)(p) to 100 F(40 C) 11(P)

NOTES TO TABLE 4

Note 1 - Table 4 is only a general guide. Before deciding on a particular material for a specificapplication all circumstances, in particular the joint movement to be expected and a suitable jointdesign (Chapter 4) and joint detail (Chapter 5) must be considered.

Note 2* - 3 refers to Tension-Compression described in

Note 3 - Certain sealantsnational restrictions that

contain substances toxic to potable water orgovern use in areas exposed to these.

Note 5 - Pot lifemixing is critical

(time material still usable after mixwith two component materials.

ing) is limited and correct proportioning

Note 6 - Field-Molded Sealants Furnished as follows:3.6.

foodstuffs. Check local or

Note 4 t - Certain materials are equally suitable for both vertical and horizontal joints. Others arenot and while they may stay in place in horizontal joints they would sag or flow out of vertical jointsin hot weather. Asphalt and rubber-asphalt materials are examples of these. Some materials are availablein two grades. One known as nonsag or gun grade is thixotropic and is suitable for vertical joints. Theother known as self-levelling or pour grade is intended for use in horizontal joints.

Liquid in Drums, cans or cartridgesLiquid in DrumsLiquid in Drums or cansLiquid in CansLiquid in Cans or cartridgesLiquid in CartridgesSolid in Cakes for Melting

for preformed Materials see Table 3

ABDERCKWOQPSLNTUVMFGHIJ

*Identifying numbers and letters are found in Tables 1 and 3.

+ With primer.


O1 E x p a n s i o nConstructionCombined

0 ContractionConstructionCombined

O3 ContractionMonolith

SEALANTS: TABLE 4; FIELD-MOLDED TYPE IV COMPRESSION SEALS TYPE VI3 ONLY

G A S K E T S V I I I : 1 3 4 5 6 7-

JOINT TYPEBUTT

EXPOSURE AND SERVICE ENVIRONMENT

Exterior Walls and Roof: rain, sun, wind, low and high temperaturesInterior Walls, Columns and Floors: dry, room temperature; traffic-light or spiked heels

Direction of exposure in sketches =

@ May behorizontalor vertical

0B As far as sealant OC Where units @ Cases @@@ ,is concerned this abut at right can be sealed onis a butt not a lapjoint

angles both sides ifrequired

i

FILLER SEAL IFREQUIRED

J

(i) Do not carry water-proofing over jointunless it is extensible

(ii) Insulate roof to reducejoint movement

OD Floor to 0 Roofs OF Isolation joint forWall columns from floor

OA May be horizontalor vertical @In floors and roofsmay be bonded andtied.

OC Between precast units - preformed gasket (i) buried or (ii) may be at surface

I

SANDBLASTI

ISTFOR BOND I

A Horizontal

8B Vertical as 2@butomit bond breakerand preferably include

I waterstop-----_ -_.- - _ _-- - _ - -

OB Cases O1 OB OC OD above used as Contraction Joints with filler omitted. Mortar bedding or grout often, used between precast units as rigid filler

(i) For large move-ments improveshape factor anduse bond breaker

Extra Tips

(ii)

for BetterPerformance WITH BACK

AS REQUIR(iii)

Where seepage may occur due to slightback pressure, steel plates and angles ormortar plugs are sometimes used on topof seal to hold it in the joint.Or better still:

Use waterstops across joint as shown inFigure 11.

Fig. 7-Joints for structures; concrete to concrete


JOINT TYPEButt Joints SometimesCombined with LapFeatures

0 & @ O f t e nCombined

4I t

0I ONE STAGE JOINTS

OI OC WALL PANEL

O2 TWO STAGE JOINTS

OD W I N D O W

OE W A L L P A N E L

EXPOSURE AND SERVICE CONDITIONS

Exterior: Rain, sun, wind, low and high temperatures. Nonconcrete materials may be at higher orlower temperatures than concrete and move differentially.

Interior: Dry moderate temperatureAppearence and color of sealant important

Direction of exposure in sketches =I I IIII~ :

l/l-)-

SEALANTS: TABLE 4 FIELD-MOLDED GENERAL CAULKING NO MOVEMENT TYPE I A-H-D-E. SOMEMOVEMENT TYPE II LM; TYPE V T-U-V- CAULKING AND SEALING LARGER MOVEMENTS; TYPE IVN-P-R-S COMPRESSION SEALS VI 3 GASKETS VIII 1 34567 MISCELLANLOUS IX TAPFS ALL AS APPROPRIATE

3A DIRECT TO CONCRETE OB WITH FRAME

ALTERNATIVES FOR @

(I) Speed (II) (‘irculdr

purpow hckup

gaket and wpport (I) llorl/ontJl

rod often used Joint

(II) VertiulJoint

SealedVerticalConnectionBetweenSections

AirSeal

RainBarrier

(1) Parapet

(iii) Vertical

Jo in t

(Ill) Horizontal

Joint

Weep

OD TWO STAGE OE TWO STAGE OC ONE STAGE

WINDOW JOINTS WALL PANEL JOINTS WALL PANEL JOINTS

Fig. 8 -Joints for buildings; special purposes

504R-19

04

Preformed tension-compression seals forsmall to large spans andmovements up to 13 in.(330 mm).

Groove Bridging plate Total movement accomodated by one or more grooves anddeformation of elastomer. Embedded or surface bridgingplates required for wider joints.

JOINT SEALANTS

JOINT TYPEUSUALLY BUTT

-I-

+I I--,Usually ExpansionConstruction Com-bined

O1

Field molded sealant forsmall spans, and move-ments generally lessthan in.3/4 (19 mm).

O2

Preformed single unitcompression seals forsmall spans, and move-ments less than 2 in.(50 mm).

O3

Preformed strip (gland)seals for small to medi-um spans, and move-ments up to 4 in.(100 mm).


Exterior: rain, sun, wind, low and high temperatures salt traffic, rubbertires, sand and debris, and possible fuel and oil droppings.


Sealants: TABLE 4, FIELD-MOLDED TYPE IIG (VERY SMALL MOVEMENTS ONLY). TYPE IV N 0 QCOMPRESSION SEALS VI 3,8 (SMALL TO VERY LARGE MOVEMENTS IX 3 TENSIONCOMPRESSION SEAL. STRIP SEALS VI 3,8.

Concrete Riding Surface Saw and seat groove Steel cover plate

0A For betterperformance, OAi Additional OAii Seal at the OB Sealed sliding

treatment for or Surface cover plate jointasphalt-

Oor

surfaced decks Bi Sealant may beunder cover plate.

Bleeder holes

Shoulder tosupport seal Concrete

end dam ,and blockout.

Retain seal byimechanicalIinterlocking

OA Single unit compres- Better-, BOsion seal Note, armored joint faces and anchorage

All devices accomodate movementby one or more folds or flexing ofa waterstop. Steel armoring andanchoring of various designs areneeded, depending on (B). Somedevices may be nosed or bedded inelastomeric concrete, e.g., right-hand side B iv.

OB Strip (gland) seal may fold:(i) Upwards A

a ( i i ) Downwards -7(must not protrude)

and may be anchored to joint faces by:(i) Clamping Down or (ii) Up

or (iii) Horizontally or (iv) Press Fit

O5

Preformed compressionor strip (gland) seal mod-ular systems for largespans and movements upto 48 in. (1220 mm).

Separation beams carrytraffic and retain seals

Preformed compression or strip (gland) seals, used in asmany modules as needed in series to accomodate totalmovement. Mechanical devices of various designs areused in conjunction with the supports to equalize move-ment between units and reduce impact and friction forces.

Note: (i) Traffic impact can cause serious damage unless joint faces are armoured and assemblies and devices securelyanchored and embedded (see 2 B and 3 B iv).

(ii) Any leakage can lead to serious deterioration of substructure, carry seals through curblines.

(iii) Longitudinal joints and skewed transverse joints induce extra strain in sealant from out-of-planemovements.

Fig. 9-Joints for bridge decks


JOINT TYPEUSUALLY BUTT

-1 I--


Below Water: wet, small temperature range, various hydrostatic pressures flow.Above Water and Dewatering: rain, sun, wind, low and high temperatures.Exterior Below Grade: ground water sulfates, organic matter, soil infiltration:

water, but may be other fluids or gases.

Direction of exposure in sketches = unless otherwise shownSEALANTS: TABLE 4, FIELD MOLDED TYPE IC, IllK (SMALL MOVEMENTS) IVN, VI 3,(LARGER MOVEMENTS) VII 1 3 4 5 6 AND 8.

@ Lining and wall jointsfor low heads

Contraction orconstruction,combined transverseor longitudinal

@ For heads @ A improved @ Corn- @ Insert @ Swellingup to 15 for heads pression (Crack Bentonite cutsft. over 15 ft. Seals inducer) off water flow

sealant

O2 Lining and wall jointsfor higher headsincluding dams

Waterstop is primarysealant, other sealantfor inside or outsideface sometimes used.

O3 Pipes, culverts, siphons, joints for low heads.

For Precast Units

@@O

~~l~df~~~~~~ads

@ for higher pressures.

Monolithic pipe jointsuse @ @ , omit bondbreaker

-

AR KEYWAYS MAY BE INCORPORATED

xi

.

.

.

\tGROUT INJECTEDTO FILLCONTRACTION \

@ Expansion Joint OB Contraction joint-GAP IN DAMS C Replaceable

vertical, horizontal Waterstopconstructed asFigure 8 @

CEMENT BITUMINOUSMORTAR REINFORCED HOT APPLIED

@ Mortar bedding-no @ Grouted spigot andsealant socket - sealed inside

OC Bituminous hotapplied-sealed outside

-

O4 Pipes and syphons withheads up to 125 ft. (38m)

@@ Commonly usedfor lower heads

@

TI I II I I@ Rubber gaskets( i ) may or may not have

steel bell ring(ii) gap between spigot

and socket may bemortared or grouted

Fig. 10- Joints for containers; canal linings, walls, dams, pipes, culverts, syphons

CEMENT MORTARREINFORCED

. *:*I I*. .. STEEL BAND..I.

Itl I-d,, Itl

@ Rubber gasketscompressed byexternal circum-

compressed betweenpipe and internalsteel ring, which mayhave asbestos cementliner

ferencial steel band


JOINT TYPEBUTT


Below Water: wet small temperature range, hydrostatic pressure, no flow.Above Water and During Dewatering: rain, sun, wind, low and high temperatures.Exterior Below Grade: ground water, sulfates, organic matter, soil infiltration.

Contents usually water but may be other fluids or gases.Appearance and color of sealant im ortant in swimming pools.

Direction of exposure in sketches =I IRll111

unless otherwise shown.

SEALANTS: TABLE 4WATERSTOPS: 1 3 4 6 8 9A 9B AND OTHER SECONDARY SEALANTS

O1 Joints in Walls

O2 Joints between walls.floors and roofs

OA Walls: Contraction OB Walls: Monolithicas Fig. lo,@@

@ Expansion asFig.10 m

without grouting or this detailbut with sealing which hasgroove on internal greater resis-face. with waterstop tance to

and often keyway. pressures.

Wall free to move Wall fixed, floor can move

either

MONOLITHICCONSTRUCTION

1 BASE

I 1 S L A B

OA Wall to floor OB Wall to floor

OE

This is alap jointsealantin shear

@ Wall to roof for @ @ Wall to roof for OB aboveabove

@ and @ will also workthe other way to keepwater out. They are thenused in building basementretaining walls, tunnels,secondary sealant on outsidewhere possible

Fillers and backupmaterials used in theapplications in Fig. 10and 11 should be waterresistant and additionallythey should support thesealant against thefluid pressure

O 3 Joints in floors Treat as for slabs on grade Fig.12 but include waterstop at middepth or bottom(where base plate shown).

O 4 How to installwaterstops

Depending on type,three methods usedin vertical joints

For horizontaljoints embed ‘/zway vertically inlower lift

@ Split forms OB Nail-on unfold @ Nail-on labyrinth

EXPANSION JOINT

2ND

Fig. 11-Jointss for containers; tanks, reservoirs, swimming pools; waterstops


JOINT TYPEINVARIABLY BUTT

@ Expansion

O 2 Contraction


Rain, sun, low and high temperatures (except inside floors); salt (highways, walkways); oil,fuel, organic deicers (airports, etc.); solvents, acid, oil (industrial floors); curling (outsideexposure); traffic, rubber tires, steel wheels (industrial floors); spiked heels (floors andwalkways); sand and debris.


SEALANTS: TABLE 4: FIELD-MOLDED TYPES II AND IV (FUEL RESISTANT IF NEEDED). COMPRESSION

SEALS VI 3 ONLY

3A Better -

Construction steps:

OULDER

(1) Preposition filler(2) Place concrete(3) Form or saw sealant reservoir(4) Seal

@ Step improves shape OBii With addition of back-up.factor. Less sealant used

O Bi Bond breaker also used

@ or better @suitable for compressionseal

Construction steps:

( 1) Form, tool or saw f/4 depthto induce crack

(2) Enlarge sealant reservoir ifneeded

(3) Seal

O A Better --+ OB Better - OBi or - BiiOOB is also suitableBetter shape factor. Even better, shapeBase plate prevents factor due to use of

for compression

subgrade infiltration back-up. Less sealant seals no back-up

needed

CRACK INDUCERSTRIP OR TAPE

Construction steps:

@ Construction ‘I 5 lrPtiELl:l_. . . .@ Transverse @ Longitudinal or @ Longitudinal with

with keyway crack inducer (4)

O Ai If filler ispositioned against @ and @ also known1st placement this as hinge (warping)will serve as jointsexpansion joint

Bulkhead fortransverse joints (A)Form keyway (B) orinduce crack (Bi) forlongitudinal jointForm or saw sealantreservoirSeal

(i)

Extra Tips forGoodPerformance

(ii)

(iii)

(iv)

Base plate (or stabilized base) will prevent infiltration of solids frombeneath, return base plate up, or sealant down, outside slab edges tokeep out shoulder material.

Seal between pavement and paved shoulder or drainage gutter.

For industrial floors armor faces, protect sealant with steel plate (similar)to Fig. 9 @ @ or (@Sealant usually installed slightly below level of pavement surface to avoidcontact with traffic. In airports flush installation may be required as anoperational safety requirement.

Fig. 12-Joints for slabs on grade; highways, airports, walkways, floors


lowing: intrusion of foreign material, wear, indentation,pickup by traffic, fire or attack by chemicals present. Furtherrequirements may be that the sealant has a specific color, re-sists change of color or is nonstaining to the substrate.

Finally, the sealant must not deteriorate when stored for areasonable time prior to use, it must be relatively easy to han-dle and install, and be free of substances harmful to the userand concrete or other material that it may abut (see Section6.14). In certain locations regulations may restrict the use of
sealants which contain solvents deemed to be pollutants.
3.3-Available materialsNo one material has the perfect properties necessary to

fully meet each and every application. It therefore is a matterof selecting a material that is economically and physically ac-ceptable for each application.

For many years oil based mastics or bituminous com-pounds and metallic materials were the only sealants avail-able. For many applications these traditional materials didnot perform well and in recent years there has been active de-velopment of many types of “elastomeric” sealants whosebehavior is largely elastic rather than plastic and which areflexible rather than rigid at normal service temperatures.Elastomeric materials are available as field molded and pre-formed sealants. Though initially more expensive, pre-formed sealants may be cheaper in the long run because theyusually have a longer service life.

Furthermore, as will be seen, they can seal joints at whichconsiderable movements occur that otherwise could not pos-sibly be sealed by the traditional field-molded materials. Thishas opened up new engineering and architectural pos-sibilities to the designer of concrete structures.

No attempt has been made in this guide to list or discussevery attribute of every sealant. Discussion is limited to thosefeatures considered important to the designer, specifier anduser so that he can make a suitable choice.

3.4-Field-molded sealants3.4.1 Mastics-Mastics are composed of a viscous liquid

rendered immobile by the addition of fibers and fillers. Theydo not usually harden, set or cure after application, but in-stead form a skin on the surface exposed to the atmosphere.Mastics listed in Table 1, Type 1, are (A) or (B) drying or non-drying oils (including oleoresinous compounds), (C) low-melting point asphalts, (D) Polybutenes, (E) Polyisobutyleneor combinations of these materials. With any of these, a widevariety of fillers is used, including fibrous talc or finely di-vided calcareous or siliceous materials. The functional ex-tension-compression range for these materials is approx-imately + 3 percent.

They may be used where only very small joint movementsare anticipated and economy of first cost outweighs that ofmaintenance or replacement. With aging, most mastics tendto harden in increasing depth as oxidation and loss of vol-atiles proceeds, thus reducing their serviceability. Poly-butene and polyisobutylene mastics have a somewhat longerservice life than do the other mastics. The main use of mas-tics is in caulking and glazing in buildings.

3.4.2 Thermoplastics, hot applied-These are materialswhich become soft on heating and stiff to hard on cooling

usually without chemical change. They are generally black,are listed in Table 1, Type II, and include: (F) asphalts, (G)rubber asphalts, (H) pitches, (I) coal tars, and (J) rubber coaltars. They are useable over an extension-compression rangeof + 5 percent. This limit is directly influenced by servicetemperatures and aging characteristics of specific materials.Though initially cheaper than some of the other sealants,their effective life is, in practice, shorter. They tend to loseelasticity and plasticity with age, to accept rather than rejectforeign materials, and extrude from joints that close tightly orthat have been overfilled. Physical properties may be ad-versely affected by overheating during installation (see Sec-tion 6.6).

Those with an asphaltic base are softened by hydrocar-bons, such as oil, gasoline, or jet fuel spillage. Tar-based ma-terials are fuel and oil resistant and are preferred for servicestations, refueling and vehicle parking areas, airfield apronsand holding pads.

The use of sealant types F, G, H, I and J are restricted tohorizontal joints because they would run out of vertical jointsduring installation or subsequently in warm weather. Theyhave been widely used in pavement joints, but they are tend-ing to be superseded by chemically curing thermosettingfield-molded sealants or compression seals. They are alsoused in building roof decks and containers.

Polyvinylchloride coal tars listed in Table 1, Type II (W)have the following enhanced characteristics and properties:

1. Do not flow at elevated service temperatures;2. Are resilient;3. Have good resistance to weathering and aging;4. Are resistant to jet fuels or other similarly aggressive

chemicals;5. The allowable extension and compression is up to + 25

percent;6. Unit cost is medium.Polyvinylchloride coal tar sealants are being used in pave-

ment and canal liner joints as illustrated in Fig. 12 and 10,respectively.

3.4.3 Thermoplastics -Cold-applied solvent or emulsiontype-These materials are set either by the release of sol-vents or the breaking of emulsions on exposure to air. Some-times they are heated to a temperature not exceeding 120 F(49 C) to facilitate application but usually they are handled atambient temperature. Release of solvent or water can causeshrinkage and increased hardness with a resulting reductionin permissible joint movement and in serviceability. Productslisted in Table 1, Type III: (K) rubber asphalts, (L) vinyl, (M)acrylics and (X) modified butyl rubbers are available in a va-riety of colors. Their maximum extension-compressionrange is + 7 percent. Heat softening and cold hardening may,however, reduce this figure.

These materials are restricted in use to joints with smallmovements. Rubber asphalts listed in Table 1, Type III (K)are used in canal linings, tanks, and fillers for cracks. TypeIII (L) vinyl, (M) acrylics and (X) modified butyl rubbers aremainly used in buildings for caulking and glazing.

3.4.4 Thermosetting, chemically curing-Sealants in thisclass are either one or two component systems which cure bychemical reaction to a solid state from the liquid form inwhich they are applied. Listed in Table 1, Type IV are (N)


polysulfide, (O) polysulfide coal tar, (P) polyurethane, (Q)polyurethane coal tar, (R) silicone, (P) urethane and (S) ep-oxy-based materials. The properties that make them suitableas sealants for a wide range of uses are their resistance toweathering and ozone, flexibility and resilience at both highand low temperatures, and inertness to a wide range of chem-icals, including, for some, solvents and fuels. In addition,the abrasion and indentation resistance of urethane sealants isabove average. Thermosetting, chemically curing sealantshave an expansion-compression range of up to: silicones+ 100/-50 percent; polyurethanes 25 percent; polysulfides 25percent; epoxy-based materials less than 25 percent.

Silicone sealants remain more flexible over a wider tem-perature range than other field-molded liquid sealants.

If substrate conditions are clean and otherwise suitable,then thermosetting, chemically curing sealants can standgreater movements than other field-molded sealants and gen-erally have a much greater service life.

3.4.5 Thermosetting solvent release-Another class ofthermosetting sealants are those which cure by the release ofsolvent. Listed in Table 1, Type V are (V) chlorosulfonatedpolyethylene, (U) butadiene styrene and (R) silicone mate-rials. Their performance characteristics generally resemblethose of thermoplastic cold applied solvent release materials(see KSection 3.4.3). They are, however, less sensitive tovariations in temperature once they have “setup” on exposureto the atmosphere. They are mainly used as sealants for jointsin buildings, where both horizontal and vertical joints havesmall movements. Their cost is somewhat less than that ofother elastomeric sealants and their service life is consideredadequate.

3.4.6 Accessory materials3.4.6.1 Primers-Where primers are required, a suit-

able priming material compatible with the sealant is usuallysuppled along with it. In the case of hot-poured field-moldedsealants, these are usually high viscosity bitumens or tars cutback with solvent. To overcome damp surfaces, wettingagents may be included in primer formulations, or materialsmay be used that preferentially wet such surfaces, such aspolyamide-cured coal tar-epoxies.

3.4.6.2 Bond breakers-Many backup materials do notadhere to sealants and thus, where these are used, no separatebond breaker is needed. Polyethylene tape, coated papersand metal foils are often used where a separate bond breakeris needed.

3.4.6.3 Backup materials-These materials serve tolimit the depth of the sealant; displacement by traffic andfluid pressure; facilitate tooling and shaping; and may serveas a bond breaker to prevent the sealant from bonding to theback of the joint. Suitable preformed materials are listed inTable 2. In selecting a backup material, it is advisable to fol-low the recommendations of the sealant manufacturer to in-sure compatability.

The backup material should preferably be compressiblewithin itself so that the sealant is not forced out as the jointcloses and it should recover as the joint opens. Care must betaken to select the correct width and shape of material so thatafter installation it is compressed approximately 50 percent.Stretching, twisting or braiding of tube or rod stock should beavoided. Backup materials and fillers containing bitumen or

volatile materials should not be used with thermosettingchemical curing field-molded sealants, since they may mi-grate to, and/or be absorbed at, joint interfaces, impairingadhesion.

3.5 Preformed sealsTables 3 and 4 cover preformed sealants for two applica-

tions, distinguished by how they are installed in the work andtheir subsequent accessibility.

Traditionally, preformed sealants have been subdividedinto two classes; rigid and flexible. Most rigid preformedsealants are metallic; examples are metal waterstops andflashing. Flexible preformed sealants are usually made fromnatural or synthetic rubbers, polyvinyl chloride and like ma-terials, and are used for waterstops, gaskets and mis-cellaneous sealing purposes. Preformed equivalents of cer-tain materials, e.g., rubber asphalts, usually categorized asfield molded, are available as a convenience to handling andinstallation.

In recent times, however, a new and very important use ofpreformed sealants has been in the form of strip (gland) seals(see Section 3.5.4). Flexible seals which can be installed in
joints open on at least one surface after the main concretingoperations are complete and may be replaced in service, ifnecessary.
3.5.1 Rigid waterstops and miscellaneous seals-Rigidwaterstops are made of steel, copper and occasionally oflead.The stiffness of steel waterstops may lead to cracking inthe adjacent concrete. Steel waterstops are primarily used indams and other heavy construction projects. Stainless steelsmay be desirable in particularly corrosive environments. An-nealing of steel, after welding, is sometimes required for im-proving its flexibility at the weldment.

Copper waterstops are used in dams and general construc-tion; they are highly resistant to corrosion, but must be han-dled with care to avoid damage. For this reason and cost,flexible waterstops are often used instead.

3.5.2 Flexible waterstops-The types of materials suit-able and in use as flexible waterstops are shown in Table 3.Butyl, neoprene and natural rubbers have good extensibilityand resistance to water or chemicals and may be formulatedto give good recovery and fatigue resistance. Polyvinyl chlo-ride (often called PVC) compounds are, however, probablynow the most widely used. While it is not quite as elastic asthe rubbers, and it recovers more slowly from deformationand is susceptible to oils, grades with sufficient flexibility(especially important at low temperatures) can be formu-lated. PVC has the great advantage of being thermoplasticand hence it can easily be spliced on the job or special config-urations made for joint intersections.

Flexible waterstops, as shown in Table 4, are widely usedas the primary sealing system in dams, tanks, monolithicpipe lines, flood walls, swimming pools, etc., to keep thewater in, and in buildings below the grade or in earth-retain-ing walls to keep the water out.

3.5.3 Gaskets and miscellaneous seals-Gaskets and ma-terial in the form of a thick ribbon (tape) are sealants widelyused with glazing and for precast concrete panels in curtainwalls. Gaskets are also extensively used at joints betweenprecast pipes and where mechanical joints are needed in serv-


CHAPTER 4-JOINT MOVEMENTAND DESIGN

4.1-DiscussionThe location and width of joints that require sealing can

only be specified with the following consideration in mind:“Is there a sealant available which will take the anticipatedmovement, and what shape factor (or in the case of pre-formed sealants - size) is required?” If the first answer is no,then the joint system for the structure must be designed toreduce the movement at the joints. Sealing systems currentlyavailable can accommodate (at increasing costs) movementsto about 48 in. (1220 mm). With due forethought it shouldtherefore be possible to design and specify a suitable sealedjoint for almost any type of concrete structure.

3.5.4 Strip (gland) seals-These sealing systems are es-sentially exposed flexible waterstops and are finding wide usein bridge expansion joints, either in single units [see Fig. 9(3)] or in series in modular systems [see Fig. 9 (5)].

Neoprene, natural rubber and EPDM (ethylene proplenediene monomer) natural rubber are the main materials cur-rently being used and, as illustrated in Fig. 9 (3), the seals areanchored at the ends and configured so that they are permittedto fold or flex as the joint opens and closes.

ice lines. Suitable materials are listed in Table 3 and uses inTable 4. The sealing action is obtained either because thesealant is compressed between the joint faces (gaskets) or be-cause the surface of the sealant, as in the case of poly-isobutylene, is pressure sensitive and thus adheres.

3.5.5 Compression seals-Preformed compression sealsare compartmentalized and extruded, to the required config-uration, from elastomeric compounds, most commonly neo-prene and EPDM. For effective sealing, sufficient contactpressure must be maintained at the joint face. This requiresthat the seal is always in some degree of compression. This isaccomplished by internal webs, which fold and flex to ac-commodate movement, yet keep the side faces of the seal incontact with the joint faces. To obtain these characteristics,good resistance to compression set (that is, the material mustrecover to its original size and shape sufficiently when re-leased) is required.

To facilitate installation of compression seals, lubricantsare used. For machine installation, additives to make the lu-bricant thixotropic (increased fluidity during agitation) havebeen found necessary. Special lubricant adhesives, whichboth prime and bond, have been formulated for use where im-proved seal to joint face contact is required.

Compression seals are effective joint sealants over a widerange of temperatures in almost all applications. Seals maybe used individually, or as components for modular systems[see Fig. 9 (5)].

3.5.6 Flexible foam (impregnated)-Another type of pre-formed compression seal is polybutylene-impregnated foam(usually a flexible open cell polyurethane). This material hasfound limited application in structures such as buildings andbridges, but its recovery at low temperature is too slow to fol-low joint movements, and when highly compressed the im-pregnant exudes and stains the concrete. This generally lim-its applications to joints where less than + 10 percentextension-compression occurs at low temperature or + 20percent where the temperature is above 50 F (10 C). The ma-terial often must be bonded to the joint faces.

3.5.7 Flexible foam (nonimpregnated)-One type of seal-ant which is in this category is a crosslinked, closed cell eth-ylene vinyl acetate expanded foam material which exhibitsgood chemical resistance properties to most mild nonoxidiz-ing acids and alkalines. It is usually custom cut to fit anyshape or size joint required. The material is heat-welded insheets and cut to lengths desired. Heat welding may be ac-complished on the job site, to either fabricate lengths or makealterations, with a PTFE-coated iron.

An adhesive compatible with ethylene vinyl acetate is usedto bond the sealant to the joint face. Based upon manufac-turer’s literature, the allowable movement should be less than50 percent of the nominal width. Although it has some ten-

sion capability, it is preferable that it not be used in tension.3.5.8 Tension-compression seal systems-Compared to

other preformed sealant materials, tension-compression sealsystems are composed of relatively massive, molded, blockstyle elastomeric material, commonly neoprene or EPDM, inwhich a metal bridging plate may be incorporated, either atits surface or embedded within.

The elastomeric element is anchored to both joint facesand movement is accommodated by a combination of groovesand shear deformation of the elastomeric component as illus-trated in Fig. 9(4). When this system is used in bridge deckexpansion joints, the elastomeric element must be tough andabrasion resistant against direct traffic loads or wear.

4.2-Determination of joint movements andlocations

The anticipated length changes within the structure mustbe determined and translated into joint locations and move-ments that not only fit the structural design and maintain theintegrity between the individual structural units, but whichalso take into account the fact that each type of sealant cur-rently available imposes specific limitations on both theshape of joint that can be sealed and the movement that can beaccommodated. It should be remembered that the sourcesand nature of the movement, both long and short term, can bevery complex in other than simple structures (see Section2.4) and that experience and judgement play a big part in de-signing joints that function satisfactorily. A more completediscussion of this is beyond the scope of this guide except todraw attention to the following simple facts, which if over-looked result in poor joint sealant performance.

1. The movement of the end of a unit depends on its effec-tive length, that is, on the length of the part of the unit that isfree to move in the direction of the joint.

2. Except where a positive anchor is a feature of the de-sign, experience shows that the preferred safe assumption isthat a joint between two units may be called upon to take thetotal movement of both units.

3. The temperatures of the materials being joined may varyfrom the ambient condition, affecting joint movements.

4. Where units to be joined are of dissimilar materials theymay not be at the same surface temperature (see Section 2.4)and the appropriate coefficient for each material must be usedin calculating its contribution to the joint movement.


PROBLEM : IA S S U M E W i - 1.0 IN.(254mm)

COMPUTED EXPANSION =0.5 IN.(l2 7mm),(50%)

MAXIMUM STRAIN FROM LAB TESTS= 60%

FROM CURVES d =,W i

dMAx= I x 1.0: I I N C H (25.4 mm)oim0 50 100 150

COMPUTED LINEAR EXPANSION - PERCENT

Note. (i) t/ dmux is less than ‘A in. (12.7 mm.) sealant may, with age lose extensibility.

Redesign joint system.

(ii) sealant free to assume parabolic shape on both faces.

(iii) factor of safety of 4 should be used in applying this chart

(iv) figure from Schutz (7).

Fig. 13 -Selection of dimensions for field-molded sealantsin butt joints

5. Where knowledge exists of actual movements that haveoccurred in similar situations, these should be considered inthe design to supplement those indicated by theory alone.

6. Allowance must be made for the practical tolerancesthat can be achieved in constructing joint openings or in cast-ing and positioning precast units.

7. In butt joints the movement to which the sealant canproperly respond is that at right angles to the plane of the jointfaces. Shearing movements in the plane of the joint facesmust be taken into account where they are large by com-parison, for example where very large skews (over 30 deg) ordeflections occur.

8. The width of the joint sealant reservoir must always begreater than the movement that can occur at the joint.

9. When viewing a structure the joints, either sealed or un-sealed, tend to stand out. It is therefore desirable to locateand construct them as a purposeful feature of the architecturaldesign or to hide them by structural or architectural details.

4.3-Selection of butt joint widths forfield-molded sealants

The selection of the width (and depth) for field-moldedsealants to accommodate the computed movement in a jointis based on the maximum strain allowable in the sealant. Thisoccurs in the outer fibers, usually when the sealant is ex-tended (see Sections 2.2, 2.4 and 2.5) though in some casesmaximum strain may occur while the sealant is compressed.The part of the total movement which extends the sealant is

the difference between the width of the joint at the time thesealant is installed and the width of the joint at its maximumopening. The temperature difference between that at installa-tion and that at maximum opening is the main contribution tothe extension of the sealant; but any residual dryingshrinkage or creep of the concrete that has yet to occur, andshrinkage in the sealant as it sets or cures, will also imposeadditional extension on the sealant.

When the suitability of a new joint sealant is first beingconsidered and a precise determination of the dimensions ofthe sealant reservoir are required, the approach using Fig. 13from Schutz5 may be followed. This figure relates the max-imum allowable strain in a sealant to an assumed joint widthand various shape factors. First, the maximum allowablestrain for the sealant under consideration must be determinedby testing at a specified temperature. Next, a likely approx-imation to the joint width is assumed and the computed linearextension that the sealant would undergo between the as-in-stalled width and the width at maximum opening of the jointis calculated.

The various curves then permit the computed extensionand shape factor to be interrelated so that the maximum al-lowable strain will not be exceeded. More than one solutionis usually possible and where the upper limits of the curvesare approached, a wider assumed joint width should be tried.In practice, to allow for unforeseen circumstances, a safetyfactor of four should be applied in using this chart.

This detailed procedure is simplified for practical use bythe aid of the percentage extension-compression shown inTable 1 for each type of field-molded sealant. This figure hasbeen derived by considering the maximum allowable strainsfor materials of each type and then applying the suggestedsafety factor. The percentage extension-compression of thesealant is the percentage increase or decrease in the as-in-stalled width of the sealant that can be safely accommodatedas the joint subsequently opens and closes. The width of thejoint to be formed, which becomes the sealant mold and thusdetermines the as-installed sealant width, can then be ob-tained by simple calculation so that in service the permissibleextension-compression range is not exceeded. This calcula-tion should, of course, take into account (a) the anticipatedtemperature at the time of forming the joint, (b) the tem-perature at sealant installation, (c) any additional joint open-ing which will be caused by initial drying shrinkage of theabutting concrete units, and (d) the extremes of service tem-perature.

When the joint width is designed, a precise installationtemperature cannot usually be known or specified; otherwise,an intolerable restriction would be placed on the installationoperation. All that can be done is to specify installationwithin a general temperature range. This can be done easilyby insuring that for the worst installation temperatures theseal will still function as anticipated (for extension the top ofthe range is used, and for compression the bottom of therange). A practical range of installation temperatures takinginto account this and other factors, such as moisture conden-sation at low temperatures and reduced working life at hightemperatures, has been determined to be from 40 to 90 F (4 to32 C). This is generally because the tension case as the jointopens with fall of temperature is the more critical to sealantbehavior (see Fig. 2 and 5). Joint sealants installed at the low

.JOINT SEALANTS 504R-27

4.5-Selection of size of compression seals forbutt joints

end of this range may be expected to perform best. A warningnote should be included on the plans that, if sealing must takeplace, for any reason, at temperatures above or below thespecified range, then a wider than specified joint may have tobe formed, or changes in the type of sealant or shape factor tosecure greater extensibility may be needed.

Detailed calculations for selection of the joint width forsealants with an expansion-compression range of + 25 per-cent (which is the most common range for the widely usedclass of thermosetting-chemical curing sealants) can be dis-pensed with by the use of Fig. 14. This has been prepared
using the previous procedures to cover the range of servicetemperatures of -20 to + 130 F (-29 to + 54 F) and other con-ditions specified in this guide.
Similar charts can be prepared for other sealants and con-ditions. In addition, most sealant manufacturers publish aidsin the form of charts or tables for the proper selection of jointwidths to suit their products.

Where a reasonable joint width (see Section 4.6) cannot bedetermined by the previous considerations, nor those that fol-low in Section 4.4 as to sealant depth, the proposed jointlayout for the structure must be redesigned to accommodatemovements tolerable to the sealant.

4.4-Selection of butt joint shape forfield-molded sealants

When a suitable joint width has been established (see Sec-tion 4.3). the appropriate depth for the sealant reservoir mustbe determined so that the sealant has a good shape (see Sec-tion 2.7). Fig. 13 can be used for this purpose. Curves fordepth-to-width ratios of 1:1, 1:2 and 1:3 are shown onthis chart. Any depth-to-width ratio may be used providedthat at the computed extension or compression expected inthe sealant the maximum allowable strain is not exceeded.The benefits in both better performance and economy of ma-terial by using the smallest possible depth-to-width ratio havealready been pointed out (see Section 2.7 and Fig. 6). Thechosen depth should generally not, however, be less than ‘/in. (12.7 mm); otherwise, with aging sealant performancemay be adversely affected. The depth of sealant is controlledby using a suitable backup material as described in Sections2.8, 3.4, 6.3 and 6.5. To obtain full benefit of a well-de-signed shape factor a bond breaker must be used behind thesealant (see Section 2.8, 3.4. 6.2 and 6.5).

A positive contact pressure must be exerted against thejoint faces at all times for compression seals to function prop-erly. The development of suitable seal configurations toachieve this, while following the principles explained byDreher,6 has been largely based on the results of trial and er-ror, laboratory and field experiments in both America and Eu-rope. Compartmentalized compression seals (see Section3.5.5) must remain compressed approximately 15 percent (at85 percent of nominal width) at maximum joint opening tomaintain sufficient contact pressure for sealing and to resistdisplacement, and generally not compressed more than 50percent (50 percent of nominal width) at maximum closing toprevent overcompression. This limit of compressibility hasbeen established by the producers and users to be at a point

when the pressure on the seal reaches 35 psi. Higher pres-sures tend to accelerate pressure decay. Pressure decay is thefailure of the elastomeric seal to regain its original shape thuslosing its sealing pressure when the joint opens.

The allowable movement of compartmentalized compres-sion seals is thus approximately 35 to 40 percent of the un-compressed seal width. The allowable movement for impreg-nated foams (see Sections 3.5.6 and 3.5.7) is less, being ofthe order of 10 percent.

The critical condition for maintaining a positive contactpressure is when the joint is fully open at low temperaturesince compression set or lack of low temperature recoverymay adversely affect sealant performance. The principle ofsize selection is similar to that for field-molded sealants inthat original uncompressed width of seal is that required tomaintain the seal within the specified compression range,taking into account the installation temperature, width of nor-mal opening and the expected movement. A detailed methodfor doing this has been described by Koz10v.~ A simplifiedchart applicable to the conditions specified in this guide isshown in Fig. 15, and for specific products, charts of seal
sizes for various applications are available from thesuppliers.
4.6-Limitations on butt joint widths andmovements for various types of sealants

The applicability of various sealants to joints of differentmovements in different types of structures is summarized ingeneral terms in Table 4 and illustrated in Fig. 7 to 12.

Field-molded sealants generally require a minimum jointwidth of % in. (6 mm) to provide an adequate reserve againstloss of material due to extrusion (see Fig. 4) or to accommo-date unexpected service conditions.

The upper limit of joint width and permissible movementvaries with the type of material used. Mastic, thermoplasticand solvent-release thermosetting sealants may be used injoints up to 1% in. (40 mm) wide with a permissible move-ment not exceeding ti in. (6 mm). Chemically curing ther-mosetting materials have been used in joints up to 4 in. (100mm) wide with movements in the order of 2 in. (50 mm),though it is more usual to confine them to joints of half thatsize to insure good performance and economy in materials.In wide joints increasing care with sealant installation is nec-essary and where subject to traffic, protection of the uppersurface against damage with a steel plate or other means isrequired.

Turning to preformed sealants, single unit compressionseals are available in widths up to 6 in. (150 mm) permittingjoints with movements of about 2% in. (63 mm) to be sealed.The smallest compression seal available can be installed in atiin. (3.2 mm) wide joint, where the movement will be neg-ligible. By placing compression seals or strip (gland) seals inmodular series [Fig. 9(5)], movements of up to 48 in. (1220mm), as in the longest suspension bridges, have been accom-modated. Tension-compression seal systems have been usedto accommodate movements of 13 in. (330 mm).

4.7-Lap joint sealant thicknessAs mentioned in Section 2.5, shear governs sealant behav-

ior in lap joints and its magnitude is related to both the move-ment that occurs and the thickness of the sealant between the

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two faces. It is usually considered that for installations madeat normal temperatures of 40 to 90 F (4 to 32 C) the thicknessof the sealant should be at least one half the anticipated move-ment and where higher or lower temperatures prevail at in-stallation, the thickness of the sealant should be equal to theanticipated movement. Where there will be no movement,the sealant thickness can be as little as ‘/s in. (3.2 mm). How-ever, in assembling concrete units a minimum thickness of ‘/in. (6.4 mm) is desirable to compensate for casting toler-ances or any irregularities in the faces.

4.8-Shape and size of rigid waterstopsMetal waterstops may be either flat stock or folded in Z or

M cross-sectional shapes. The choice depends on the move-ment at the joint. End anchored flat shapes permit little or nomovement without inducing excessive stresses in the embed-ded portion of the waterstop. Coating one end with asphalt topermit sliding yet maintain some sealing compatibility maynot be entirely satisfactory because leaks may eventually oc-cur. The Z cross section can accommodate slight movementsand the M cross section greater movements.

4.9-Shape and size of flexible waterstopsFor certain applications, flat shapes may be used but the

traditional shape for flexible waterstops has a dumbbell con-figuration at each end intended to serve both as an anchorand, by pulling it inwards towards the joint as it opens, it actsas a “cork in a bottle” type of seal. This seal is not too effec-tive at small openings and the material is in considerable ten-sion at wider joint openings. To overcome these problems,quite elaborate shapes have been developed in recent years.Numerous ribs at the end now provide better anchoring andsealing, and O or U bulbs at the joint gap permit considerablejoint movements to be accommodated without undulystretching the material. Manufacturers may be helpful withrecommendations.

For easier installation, both rubber and PVC waterstops areoften specified in thicknesses greater than that required fortheir function as sealants.

4.10-Shape and size of gaskets andmiscellaneous seals

Seals used for concrete pipes or building components areusually sized and shaped to suit the joint configuration in-cluding the irregularity of the surfaces being joined. Sincethe movement is small, the width of the sealant may not bethe primary consideration. Square, rectangular, trapezoidal,O-ring and H, U and W purposely made shapes, some withribs, flanges and serrations, are used depending on the ap-plication and how they can be installed. Pressure sensitivetapes of suitable widths are used as auxiliary materials tomake window and door frames or panels weathertight.

4.11-Measurement of joint movementsA better understanding of in-service joint movements in all

types of concrete structures is needed in order to confirm thetheories and laboratory experiments upon which the designprediction of joint widths and sealant performance are based.The factors which influence the movement of joints and thefunctional performance of sealants are discussed in Chapters1 and 2 and the preceding part of Chapter 4.

In view of the many variables involved, it is impossible tospecify a standard procedure for the observation and assem-bly of data on joint movements, the causative factors andsealant behavior. However, it is important that both the shortterm rates of movement over a matter of hours or days and thelong term extremes of movements over the annual environ-mental cycle together with any permanent changes in inter-facial joint distance are established.

4.11.1 Means of measuring joint movements-Handgages, either a simple vernier caliper or reference bar with adial gage, may be used to measure the distance between refer-ence plugs set on each side of the joint. While this system issimple it only provides a discontinuous record and requiresan operator to make each reading. To overcome these disad-vantages a scratch gage may be employed. These gages havea scratch probe fixed to one side of the joint opening and aplate or a hand or power rotated disc attached to the otherside. The trace of the movement over the movement cycle isthen measured. The next stage of sophistication is to use anelectronic gage. Usually this is a transducer (or LVDT forgreater precision at a greater cost) to measure the movementwhich is then recorded continuously or intermittently on astrip chart or digitally for later analysis.

In most structures the measured movement of concern tosealant performance is horizontal (across the plane of thejoint). In skewed joints, lateral movement (along the plane ofthe joint) may also need to be measured or calculated since askew introduces shear in the sealant. Vertical movements (atright angles to the plane of the joint) can be measured by fastresponse transducers where, as in pavements, moving loadscross the joint. Measurement of other dynamic effects suchas vehicle braking, impact and noise generation require spe-cialized instruments.

Absolute measurements of the relative positions of struc-tural members can be made using standard survey practicetechniques against a reference datum clear of the structure.

4.11.2 Corresponding measurements of temperature andmoisture content-Corresponding data on the thermal andmoisture dependent behavior of abutting structural units areneeded to fully interpret joint movement measurements. Re-sponse to ambient temperature change and solar radiation ismuch greater and faster than that due to seasonal changes inmoisture content in the concrete. Since moisture content isdifficult to measure and is unlikely to significantly affect theoverall findings, it is often ignored.

Where a continuous record is needed, ambient, surface orinternal temperatures are easy to measure by thermocouplesand record on a strip chart or digitally for analysis. It must beremembered that, while surface temperature changes inducewarping and curling fairly rapidly in thin sections, the inter-nal temperatures of a structural unit control its overall dimen-sions and hence the end movements at joints. Especially inmassive concrete sections there is a considerable time lag be-tween change in external and internal temperatures. Thismust be taken into account in determining any corre-spondence between temperature and movement measure-ments. In massive sections or where the structural configura-tion is complex or where differential heating because of sunand shade is significant it may be prudent also to measureheat flow and solar radiation. Notwithstanding all these cau-tions, as a minimum observation, a thermometer reading of


CHAPTER 6-INSTALLATION OF SEALANTS6.1-Introduction

The most appropriate technique for installing (applying) ajoint sealant depends on the material, the width, shape, in-clination, and accessibility of the joint and on whether it is asmall or large project. Each step in the construction and prep-aration of the joint to receive the sealant and for its installa-tion requires careful workmanship and thorough inspectionto avoid initial defects that may be costly and time consumingto correct.

The specification for the work should state how the se-lected sealant is to be installed and any special features re-quired in the construction or preparation of the joint to re-ceive it. Before the containers of sealant are opened, theirlabels should be checked to make sure that the right sealanthas been supplied and that there is no conflict between the

CHAPTER 5-JOINT DETAILS

ambient shade temperature should accompany any singlemeasurement of joint width.

4.11.3 Survey of joint sealantperformance-In addition tothe measurement of movements and the factors that causethese movements, it is important to note the condition of theinstalled sealant, joint hardware and abutting concrete as partof any overall appraisal of joint performance.

5.1-IntroductionFig. 7 through 12 illustrate the application of joint sealants

to a wide variety of design configurations which occur in con-crete construction (for a key to symbols see Appendix A).
The details shown are representative of current practice andcover most standard variations, although other variations inuse may not be shown. These details are presented in outlineform, omitting for the sake of clarity structural details such asreinforcing steel, dowels, etc., not directly relevant to thesealing of the joint. The location of a joint is indicated onlywhere this is significant to delineate the type of joint and seal-ant that may be suitable. As stated in Sections 1.5 and 4.2, thelocation and spacing of joints for particular applications isbeyond the scope of this guide. Similarly, sealant reservoirs(grooves) and expansion or contraction gaps are not dimen-sioned as to width or depth because differing sealants have awide range of performance capabilities. The required config-uration should be determined as outlined in Chapter 4 and/ormay be obtained from supplier’s literature.
Exposure and environmental service conditions are shownfor each group of applications, since this is an important con-sideration in selecting a suitable sealant.

Often, alternatives exist for a particular application.Therefore no endorsement is intended for selecting one detailover another, or choosing one sealant rather than another. Theguide does endorse and promote those standard design fea-tures documented throughout the guide (e.g., improving theshape factor of field-molded sealants) that will insure the bestpossible performance of any given seal or sealant.

5.2-StructuresFig. 7 and 8 cover applications to structures in general and

buildings in particular, where sealing against significant fluidpressure is not a consideration. Where ground water must beexcluded, as for example in basements or earth-retainingwalls, reference should also be made to Fig. 11 since addi-tional sealing using waterstops may be indicated. Since theappearance of sealed joints in many buildings is important,additional architectural treatment not shown in the figures,for example, V-ing of joint edges may be required.

Bridge deck joints are treated separately in Fig. 9, sincelarge movements and special sealing problems are often in-volved. Joint details suitable for bridge substructures gener-ally follow those in Fig. 7, or where water pressure is in-volved those shown in Fig. 11.

Containers of all types are covered in Fig. 10 and 11. Ex-cept where the head is small, the use of waterstops in “inplace construction” or gaskets under compression for precastpipes is almost essential if the contents are to be kept in. In

certain uses, for example dams, a second waterstop may beused some distance behind the first as an additional line ofinsurance against premature failure.

Many of the details shown in Fig. 10 and 11 also serveequally well for keeping water which is outside the structurefrom passing through the joint to the inside face. The exclu-sion of water from basements, subways and tunnels are exam-ples of this application. Tunnel applications are discussed ingreater detail in ACI 504.lR.

5.3-Slabs on grade, highway, and airportsSlabs on grade are shown in Fig. 12. These may be outside

as on highways, parking garages and airports, or they may bewithin a building or container with the modifications indi-cated in the figures specific to these applications.

Many highway authorities are specifying short contractionjoint spacings in both plain and reinforced concrete pave-ments; some are using a random spacing averaging between15 and 20 ft (4.57 and 6.10 m) in plain pavements for whichthe repeating series 13, 18, 19, 12 ft (4.0, 5.5, 5.8, 3.7 m) ispopular; some are also skewing joints at 2 ft in 12 ft (0.61 m in3.66 m). While the objectives are reducing intermediate slabcracking and improving ride and load transfer, such designsplace less demand on the sealant because of the smallermovement that occurs at each joint. Fuller information on thedesign and construction of joints in concrete pavements willbe found in the reports of ACI Committee 325.

5.4-Construction and installationconsiderations

The practical aspects of constructing the joint and sealingit must be kept in mind when its details are being designed.The general construction steps for any expansion, contrac-tion and construction joints are stated in Fig. 12. The methodof making monolithic construction joints is outlined in Fig. 7(3). Fig. 9 (2B) shows the blockout required where later in-stallation of expansion joint devices is planned. The position-ing of waterstops is shown in Fig. 11 (4) and further discus-sion on their installation and that of sealants in generalfollows in Chapter 6. It must be remembered that a joint de-tail that makes it unnecessarily difficult to install the sealantis a poor one likely to lead to premature failure.


6.6-Installation of field-molded sealants,hot applied

As noted in Table 4, certain joint sealants are melted andapplied hot in the field. These hot-poured compounds areusually comprised of bituminous materials (either asphalt ortar) and may or may not contain rubber or other elastomericsubstances. Each has a manufacturer’s recommended pourpoint as well as a safe heating temperature which should notbe exceeded. The safe heating temperature usually is 20 F (11C) above the recommended pour temperature. Subjectingsealants to temperatures above the safe heating limit results ina breakdown or setting up of the compound which precludesgood field performance as well as longevity.

These materials are usually heated in double-boiler typemelting kettles equipped with a suitable agitation system inthe sealant melting chamber, a positive, pressure deliveryand recirculation system and a recording thermometer. Theinner tank should be oil-jacketed and the temperature of thehigh flash point heat transfer oil should be thermostatically

specification and the manufacturer’s instructions for installa-tion. Any discrepancy should be referred to the architect orengineer before work commences.

The most auspicious time for installing field-molded seal-ants, if the construction schedule permits, is on dry dayswhen the temperature is close to the annual mean. Compres-sion seals, especially the large ones, are easiest to install oncold days. However, a satisfactory job can and usually mustbe done in less than ideal conditions provided the effects ofthis are compensated for in the design of the joint.

Sealant storage and installation requirements are summa-rized for each material in Table 4. These operations are dis-cussed in greater detail as follows.

6.2-Joint construction with sealing in mindSome of the defects resulting from improper concrete joint

construction are shown in Fig. 16. These and others can beavoided by the following:

1. Saw or form the joint to the required (and uniform)depth, width and location shown on the plans. Manufactureprecast units to close tolerances and position them carefully.

2. Align the joint with any connecting joints to avoidblockage to free movement.

3. Judge the time of sawing to avoid edge spalling orplucked aggregate (too early) or random cracks (too late).

4. Correctly position dowels and other joint hardware, fill-ers, waterstops and bulkheads, and rigidly support them toavoid displacement during concreting.

5. Remove any temporary material or filler used to formthe sealant reservoir by raking out or rotary cutting to thespecified depth.

6. Keep curing compound and other materials from con-taminating joint faces. Apply supplemental curing where theoriginal curing is broken by construction operations beforethe joint edges and faces have fully cured.

6.3-Preparation of joint surfacesJoint faces must be clean and free of defects that would im-

pair bond with field-molded sealants or prevent uniform con-tact of preformed sealants. Removal of contaminants may re-quire washing out of debris left by sawing and wire brushingor routing and sand blasting. Though sand blasting is moreexpensive, it is more likely to succeed and therefore is war-ranted where relatively expensive thermosetting, chemicalcuring field-molded sealants are used.

Solvents intended to remove oil, etc., usually have the op-posite effect and carry the contaminants further into the poresof the concrete. Solvents are, however, distinctly useful incleaning nonporous surfaces such as glass or metal frames.Defects in the joint faces such as loose aggregate, embeddedforeign material and spalls in the case of compression seals orblockages to free movement require repair (see Section7.2.1). Final cleanup to remove dust is usually required. Thisis essential where a good bond must be developed with chem-ically curing thermosetting field-molded sealants. Finalcleanup can be done by a brush, but the use of oil-free com-pressed air or vacuum cleaner is more likely to be successful.

As a general rule, joint faces must also be dry since thesealant has to bond with the concrete. Exceptions are claimedby sealant manufacturers. They include neoprene compres-sion seals and emulsion and certain elastomeric sealants for-

mulated to displace water from contact faces. Not withstand-ing, better results will be achieved if sealant installation isdone in the dry.

6.4-Inspection of readiness to sealInspection of each joint to insure it is sufficiently clean and

dry is essential prior to placing backup materials, priming orsealant installation. It is also wise to check the joint widthand temperature (preferably that of the concrete rather thanthe ambient) against assumptions made in the joint design.Restrictions on joint width and temperature at the time ofsealant installation should be shown on the plans. In the ab-sence of these, installations at above 90 F (32 C) or below 40F (4 C) should generally be avoided. Installation at tem-peratures above or below these values may lead to various dif-ficulties. Extra strains may be induced on field-molded seal-ants (see Section 4.3). Problems may arise due to shortenedworking life at higher temperatures or moisture condensationand frost at lower ones. In the case of compression seals, it isharder to properly install them in tight joints or the lubricantmay be too fluid or viscous.

6.5-Priming, installation of backup materials andbond breakers

Where priming is required with the selected field-moldedsealant the necessary primer is usually supplied with the seal-ant and can be applied by brush or spray. (As a general rulepriming is required for all porous surfaces such as concrete,wood, and possibly plastics if thermosetting, chemical cur-ing field-molded sealants are to adhere satisfactorily). Brush-ing can be tedious and unless excess material is properlybrushed out to insure a uniform film over the whole joint face,adhesion failures may result. For horizontal joints on largerprojects, spray applicators may be more appropriate. Mostprimers require time to dry out before the sealant is installed.Failure to permit this action may lead to adhesion failure orexudation of the primer.

Backup materials and/or bond breakers require position-ing, usually by hand method, before the sealant is installed.They must be set at the correct depth avoiding twisting orcontamination of the cleaned joint faces.


Random cracksassociated withexpansion joint

-possible causes

Random cracksin plan-possiblecauses

Other Defects

*

Note in examples A B C D E F G movement will occur at the crack and not at the‘intended’ joint. Therefore, the crack rather than the joint should be sealed if repairs (whichwould be desirable) are not undertaken to correct the underlying cause.

INITIAL CRACK

PLUG OF CONCRETEBETWEEN SEALANTAND FILLER

@ Sealant reservoir (groove) @ Filler displaced during @ Sealant reservoirnot formed or sawn deep concreting narrower than fillerenough (or off center)

And also for short cracks and spalls Fig. 3 @ @ and Fig. 4 @@@

OD Crack followsand/or crosses

joint late after

MAYBESOMEDISTANCEAPART

01 RECTIONOF SAWING.

I

1

SLAB EDGEv

k--@(i) Crack ran ahead @ Sealant reservoir OG Joints at intersection

of sawing to (groove) or crack were not lined up.slab edge due inducer not deep Crack occurs toto late cutting enough to form complete omitted

(ii) Infiltration of plane of weakness continuityincompressible at desired joint

crack had alreadyformed

material fromshoulder

location

Joint opening not formed(or sawn) with uniformwidth (or depth). Whilemovement is the samesealant has varying shape

@ Edge spalled when grooveformer was removed or duringsawing. Inadequate bearing forcompression seal or poor shapefactor for field molded sealants

Fig. 16-Defects in joint construction

ACI COMMITTEE REPORT

controlled. Earlier models of melters were of the gravity-feedtype and some required the use of separate pouring devices.These are preferably oil-jacketed also, but all suitable unitswere insulated. The newer melting kettles equipped withpressure discharge through hoses, wands and nozzles shouldhave the application lines insulated.

Hot-poured materials are normally suitable for installationin horizontal joints only. They can be placed in vertical jointsbut adequate dams are necessary to prevent the sealant fromflowing to the bottom before it cools and sets. Horizontaljoints should be underfilled to slightly below the pavementsurface.

6.7-Installation of field-molded sealants,cold applied

Except for extremely short joints or in touch up work, coldapplied sealants are usually extruded under pressure from anozzle whose orifice may be sized and shaped to mold therequired bead of sealant to suit the joint opening. The sim-plest piece of equipment for this purpose is the familiar handoperated caulking gun. The sealant is either supplied pre-packaged in cartridges to suit the gun, or the chamber or car-tridges are loaded on the job from bulk containers as re-quired, or in the case of two-component sealants, they arefilled with the compound after mixing. Depending on the sizeof the project, more sophisticated pressure application equip-ment is available including models where two-componentmaterials are brought by individual lines to the nozzle wherethey are intimately and continuously mixed in a small cham-ber immediately prior to extrusion. Pumps, compressed airor gas may be used to supply the necessary pressure forextrusion.

With two-component sealing, full and intimate mixing isessential if the material is to cure out with uniform proper-ties. Little can be done with patches of sealant that do notharden except to remove and replace them with properlymixed material. Small quantities of two component sealantscan be mixed with a broad bladed putty knife. However, forany significant quantity of material, mechanical mixing is re-quired. For small batches hand held electric drills with pad-

dle blades can be used. Large batches need purposely mademixing machines.

Frequently, it is convenient to premix sealants at a locationremote from the job site. To prevent curing until it is time touse them, sealants may be frozen at -40 F (-40 C) or belowand held in storage. In some urban areas frozen premixed car-tridges are available from sealant suppliers. On the job, car-tridges are thawed out for about 30 min at a temperature of 70F (21 C) (additional heating to hasten thawing may be detri-mental and should not be used).

Application of a sealant to fill a joint reservoir requires askilled operator. The gun nozzle must be controlled at an an-gle (about 45 deg) and moved steadily along the joint so that auniform bead is applied without dragging, tearing or leavingunfilled spaces. A skilled applicator will be seen to push thebead rather than draw it with the gun leading. In large joints,several runs may be needed, building up the sealants inroughly triangular wedges at each run.

For nonsag sealants, when the joint has been filled with therequired amount of material it is tooled to insure intimate

contact with the joint faces, to remove any trapped air orvoids, to consolidate the material, and to provide a neat, uni-form appearance. At the joint faces the exposed face of thesealant should usually match the level of the edge of the con-crete. An exception is in areas subject to traffic where self-leveling sealants are used. In this case the surface should beleft slightly low.

It must be remembered that two-component sealants inparticular have a limited working (pot) life, especially on hotdays. Once the accelerator is mixed in, the curing reactionstarts, therefore the batch size should be limited to what canbe used within the pot life of the material.

6.8-Installation of compression sealsCompression seals require a uniform joint width along the

whole length with straight, smooth, spall-free, properlycleaned joint faces to permit proper installation and to pro-vide uniform contact. It is advantageous to remove sharp ar-rises at the joint edge or to form or saw the joint with a slightrounded or V-edge.

A neoprene-based or other lubricant (which may have ad-hesive properties for most applications) is applied in a bead tothe upper edge of each joint face to facilitate installation ofthe seal. The lubricant is fluid at normal temperatures and isusually applied by a hand-pressure applicator. Where ma-chine installation of the sealant is used for pavement joints,this unit may also be designed to apply the lubricant, whichthen generally should be a thixotropic formulation. The lu-bricant must be applied immediately ahead of inserting theseal so that it does not prematurely dry out.

For installation either by hand roller or with the machine,the seal is positioned vertically over the joint opening andthen, by pressing down and forward, it is forced into theopening. The seal must not be twisted, folded over on itselfor stretched during this operation. A small permissablyamount of stretching, up to 5 percent, may occur as the seal isforced in. The seal must not be willfully stretched (thus re-ducing its cross section) to make installation easier and theseal length go further. Near zero stretch can be achieved withboth hand and automatic machine installation which may bedesirable since the seal will not be under tension along itslength nor reduced in effective width.

It is important to install the seal at the specified depth. Inhighway pavements, this is usually slightly below the surfaceto keep it out of contact with traffic. The seal should be in-stalled in as long a continuous piece as possible. If fieldsplices cannot be avoided they should be made in the leastcritical location as far as maintaining a sealed joint is con-cerned. Usually the seal is spliced simply by butting itagainst the next length with some lubricant adhesive. How-ever, more sophisticated means are available and may be war-ranted where it is important that a splice should not part.

Where a compression seal is to be installed between pre-cast units, it may be attached to the face of one and com-pressed as the adjacent unit is positioned.

The polybutylene impregnated foam type of compressionseal is precompressed and inserted in the joint opening. Toachieve a good bond, the joint faces may first require primingwith an epoxy adhesive. Other cellular foams such as eth-ylene vinyl acetate are installed in a similar fashion.


6.14-Safety precautionsThere are certain hazards in using joint sealants. They can

be minimized, however, by taking simple precautions. Spe-cific warnings are stated on the containers together with ac-tion or antidote in case of accident. In addition, materialsafety data sheets (MSDS) are required by law and should beavailable for all products. Users of joint materials should ex-pect to receive MSDS with the best information regarding theuse of the particular material they will be handling.

1. Hot-applied materials can cause serious bums or a firemay be set if flammable materials are spilled. Excessivebreathing of fumes or skin contact with coal tar compoundsmay cause irritation.

2. Cold-applied materials (other than emulsions) andprimers may contain flammable solvents. Containers shouldbe kept closed and away from flames. Working areas must bewell ventilated.

6.9-Installation of preassembled devicesPlacing large seals 4 in. (100 mm) and over in bridge and

other large movement joints presents special problems.Firstly, these seals are not particularly easy to handle andthey cannot be bent or formed to suit an abrupt change of di-rection. Secondly, they require considerable force to com-press them as they are pushed and levered into the opening,especially if it is a warm day and the joint is partly closedbeyond its mid-range. For this reason (and because the sealmust be sized to the joint opening), there is merit in joint de-vices which are installed as a complete unit prior to concret-ing with the seal precompressed or preset to the requiredwidth. The joint is activated after the concrete has set by re-leasing the ties connecting the joint faces. Strip (gland) sealsand modular systems designed to accommodate large move-ments are similarly supplied precompressed or preset, readyfor installation and subsequent activation.

Tension compression devices as used in bridge decks (seeFig. 9) require setting flush with the pavement surface. Ex-cept where a subsequent bituminous surfacing is to be laid,this requires a recess in the concrete surface on each side ofthe joint. Provision for the holddown bolts required for themechanical anchoring of the device can be made either bypre-setting inserts using a template when the concrete isplaced, or subsequently by drilling and installing the anchorsafter the concrete is set.

In cases where the anchorage units are preattached to theedge elements (strip seals and armored type systems) the ex-pansion joint is set to line and grade and then the concrete isplaced.

6.10-Installation of waterstopsThree methods of positioning waterstops in vertical joints

are shown in Fig. 11 (4). Of these, placing between splitforms is still the most common, though nail-on types may bemore convenient and economical. In horizontal joints, water-stops are usually embedded halfway into the first lift. In allinstances, the waterstop should be securely held in positionso that it will not be displaced during concreting, and care isrequired in placing and consolidating the concrete so that novoids or honeycombing occurs adjacent to the waterstops toprejudice its sealing ability. Contamination of the waterstopsurfaces, for example, by form coatings, should be avoided.While rubber and polyvinyl chloride waterstops are not sus-ceptible to damage during normal handling or concreting op-erations, thin metal waterstops are easily bent or torn andtherefore require special care.

Waterstops may need splicing at intersections, abruptchanges of direction or to form long continuous lengths. It isoften convenient to order prefabricated junction pieces fromthe manufacturer so that these can be joined to the main runby simple butt splices in the field. Polyvinyl chloride water-stops can be spliced by trimming their ends to the requiredmatching shape and then butt-welding them together by soft-ening under heat and pressing them together until cool. Sinceexcess heat or an open flame would char the material and de-stroy its resilience, thermostatically controlled electric heat-ing tools should be used. Rubber waterstops can be joined bymitering the ends to mate and, after cleaning and roughen-ing, cementing them together. They must then be held in a

mold under heat and pressure until cured (vulcanized). Analternative is to use premolded splicing sleeves into whoseopposite sides the cemented ends of the waterstop areinserted.

6.11-Installation of gasketsGaskets are either positioned in the joint opening or are

prepositioned because they are attached to one of the units tobe joined, for example, on the spigot end of the pipe. Posi-tioning the unit in place closes the joint on the gasket which,under pressure, then forms the seal.

6.12-Installation of fillersMost compressible fillers in expansion joints are installed

ahead of the concreting operation in the required location andposition, and held either by the bulkhead if it is a constructionjoint, or by some rigid device at other expansion joint loca-tions until the concrete has been placed and set. Problems ofthe type illustrated in Fig. 16 have often occurred because duecare and attention has not been given to making sure fillersare accurately positioned and/or are not displaced.

6.13-Neatness and cleanupNothing esthetically looks worse on a new structure than a

sloppy job of joint sealing in which the sealant is uneven or isadhering to everything except the joint faces. Careful work-manship such as uniform depth of installation, proper toolingand lack of spilled or excess material on surfaces adjacent tothe joint are all signs of a good, conscientious job.

A very neat joint can be obtained with field-molded seal-ants if strips of masking tape are first placed on each side ofthe joint opening. These can be later removed carrying anyexcess sealant with them. Proper cleaning of equipment andtools immediately after their use ceases, for even a short pe-riod, will avoid contamination of the work or delays due tohardened sealant on their surfaces. The instructions on thecontainers of cold applied sealants usually list suitable sol-vents for this purpose. Unused hot applied sealants must notbe allowed to set up in heating vessels and applicator equip-ment.


7.2.2 At cracks-Where cracks have occurred because ofa nonworking or absent joint, or because of unanticipated de-formation of the structure, they can be routed out and sealedwith a suitable field-molded sealant to prevent damage to thestructure. ACI Committee 224 has done considerable work inthis area and their information regarding repairing of crackswould be of significant help. (See ACI 224.1R). An addi-tional problem occurs where water is flowing through thecrack and the upstream face cannot be reached for sealing.Before sealing can be successfully undertaken, the waterflow must be stopped. If the source of water cannot be cut offby dewatering, then depending on the circumstances one ofthe many alternatives such as cutting back the crack deeperand plugging with a quick setting or dry-pack mortar or ce-ment, chemical or epoxy resin grouting may be tried. Exter-nal plates are sometimes bolted to the concrete, or keyedgrooves are filled with mortar to hold the sealant in case waterpressure redevelops as the joint moves. Successful executionof any of these operations usually requires specialized knowl-edge, experience and workmanship.

3. Toxic chemicals may be present in many elastomericsealants. Skin, eye or internal contact must be avoided. Pro-tective gloves and sometimes masks and goggles are re-quired. Lunch pails should not be opened until the operatorhas cleaned up.

4. Sealants containing poisonous chemicals, for example,lead dioxide, may not be appropriate in joints open to potablewater or food processing areas.

5. Most liquid sealants are highly sensitive to liquid oxy-gen (LOX) creating a serious safety problem. The chemicalsin sealants are in a state such that they can easily react withoxygen to promote explosion and/or toxic gases. Special ma-terials have been developed for exposure to LOX; however,they are usually not durable and a service life of 12 monthsduration is as long as the user/owner should anticipate beforereplacement. Loss of bond may result in a safety hazard byallowing infiltration of LOX where otherwise inert materialswill become highly reactive due to contamination.

6. Since many joint sealants are combustible organic ma-terials, attention should be given to their effect on the fire re-sistance of the structure.

7. Solvents used in clean up or released during curing maybe restricted by some jurisdictions since they are deemed tobe atmospheric pollutants even though nonhazardous.

CHAPTER 7-PERFORMANCE, REPAIR,AND MAINTENANCE OF SEALANTS

7.1-Poor performanceMuch experience of poor sealant performance and result-

ing damage to a wide variety of structures exists. Concernwith problems arising from the use of low grade asphalts andasphaltic sealants spurred the development and introductionof higher class sealants, both field-molded and preformed.Failures have continued to occur, however, often within daysand weeks of installation rather than months or years, for fivemain reasons:

1. Design of the joint geometry was insufficient to accom-modate the movement.

2. Unanticipated service conditions resulted in greaterjoint movements than those allowed for when the joint designand type of sealant were determined.

3. The wrong type of sealant for the particular conditionswas selected, often on the false grounds of economy in firstcost.

4. New sealants have sometimes been initially over-promoted and used before their limitations were docu-mented.

5. Poor workmanship occurred during joint constructionand preparation to receive the sealant or sealant installation.

Some of the common problems with joints are shown inFig. 3, 4 and 16, together with advice as to how these defectsmay be avoided in future work.

7.2-Repairs of concrete defects andreplacement of sealants

7.2.l At joints-Minor touch-up of small gaps and soft orhard spots in field-molded sealants can usually be made withthe same sealant. However, where the failure is extensive it isusually necessary to remove the sealant and replace it.

Where the sealant has generally failed but has not come outof the sealing groove it can be removed using hand tools, oron larger projects such as pavements, by routing or plowingwith suitable tools. Alternatively, especially where wideningis required to improve the shape factor, the sealant reservoircan be enlarged by sawing.

After proper preparation to insure clean joint faces and ad-ditional measures designed to improve sealant performancesuch as the improvement of shape factor, provision of backupmaterial, and possible selection of a better type of sealant, thejoint may be resealed as described earlier.

Minor edge spalls to concrete joint faces may be repairedwith suitable repair materials, an essential operation if a com-pression seal is being used. Otherwise most repairs to correctdefects in the original construction of the joint involve major,exacting and often expensive work. The reason for the failuremust be identified and, depending on the cause, continuitymust be restored in the joint system either by the removal ofwhatever is blocking the free working of the joint or by cut-ting out the whole joint and rebuilding it.

7.3-Normal maintenanceFew exposed sealants have a life as long as that of the struc-

ture whose joints they are intended to seal. Fortunately, bur-ied sealants such as waterstops and gaskets have a long lifebecause they are not exposed to weathering and other deterio-rating influences.

Most field-molded or preformed sealants will, however,require renewal sooner or later if an effective seal is to bemaintained and deterioration of the structure is to be avoided.The time at which this becomes necessary is determined byservice conditions, by the type of material used and whetherany defects of the kind already enumerated were built in at thetime of the original sealing.

The opportunity should be taken when inspections arebeing made for other purposes, or in the case of buildingswhen the facade is cleaned, to establish the condition ofsealed joints and whether resealing is required immediatelyor is likely to be required in the near future. Far too often, inthe past, resealing has been postponed either because of lack


of knowledge that it was needed or failure to budget ahead,with inevitable costly consequences.

Sealant renewal follows closely the methods listed underthe repair of defects (see Section 7.2). When renewal isneeded prematurely, consideration must be given to improv-ing the sealing system from that originally used, otherwisemoney will be wasted since failure may soon recur. Ways ofevaluating this have already been described.

CHAPTER 8-SEALING IN THE FUTUREAND CONCLUDING REMARKS

8.1-What is now possibleThe cost of providing well-sealed joints by using the best

available sealants, carefully installed in joints of the correcttype, size and location, is usually only a small fraction of thetotal cost of a concrete structure. The available sealants andknowledge of the criteria for joint sealing are now adequateto insure success in at least 9 out of 10 situations; there is nojustification for poor sealing practices when the very integrityand service life of a structure may be at stake.

8.2-Advancements still needed8.2.1 Since joint sealing is done in a wide variety of en-

vironments with a large array of differing sealant materialsunder conditions less than optimum their performance is usu-ally less than perfect. The satisfactory working life of seal-ants still requires improvement in that we can expect as low asone year of performance to generally five years of perform-ance for most sealants. Modern structures are being designedto minimize maintenance and designers are looking for highperformance sealants with life cycles of 10 to 20 years.

It takes several years after the time of initial installation toevaluate the performance of a particular sealant. After severalyears have passed, the long term performance and ca-pabilities of a sealant become evident for a given type of jointor application. Obviously some sealants perform better thanothers. As a result, manufacturers are constantly improving aparticular sealant’s ability to perform. Thus this manual mustbe constantly updated to provide the latest information.

8.2.2 Research and development work is still required toimprove:

1. Knowledge of the movements which actually occur inevery type of concrete structure.

2. The materials available for use as joint sealants. Thechallenge is to achieve good performance in a wide variety ofjoints that are wet and dirty when the sealant is installed.

3. The methods by which sealants may be installed so thathuman error is avoided as far as possible.

4. Techniques for resealing leaking joints and cracks.8.2.3 Spreading the word-Public authorities and sealant

manufacturers and suppliers have been the source of copioustechnical data and advice that has greatly benefitted the art ofjoint design and sealing. However, many of the current seal-ant problems will continue unless improvements are made indisseminating and applying available knowledge and upgrad-ing skills. For example, improvements are required in:

1. Making designers more aware of the importance of jointdesign and the selection of suitable sealants.

2. Providing clear instructions on the plans, in the specifi-cations and on the sealant containers so that the workers onthe job can understand and implement what is required.

3. Educating and training at all levels of responsibility sothat joint sealing is no longer regarded as a necessary evil tobe left to the last moment for the low man of the scaffold.

8.2.4 Future codes, standards, recommended practicesand specifications-Appropriate criteria should be includedin the contract documents for joints in concrete structures (lo-cation, type, movement determination, width, shape, sealantselection and installation criteria).

CHAPTER 9-REFERENCES1. ACI Committee 504, “Revisions to Guide to Joint Sealants for Con-

crete Structures, ” ACI JOURNAL, Proceedings V. 74, No. 6, June 1977, pp.238-254.

2. Joint Sealing & Bearing Systems for Concrete Structures, SP-70,American Concrete Institute, Detroit, 1981, 2006 pp.

3. Joint Sealing & Bearing Systems for Concrete Structures, SP-94,American Concrete Institute, Detroit, 1986, 1553 pp.

4. Tons, Egons, “A Theoretical Approach to Design of a Road JointSeal,” Bulletin No. 229, Highway Research Board, 1959, pp. 20-44.

5. Schutz, Raymond J.,, “Shape Factor in Joint Design,” Civil Engineer-ing-ASCE, V. 32, No. 10, Oct. 1962, pp. 32-36.

6. Dreher, Donald, “A Structural Approach to Sealing Joints in Con-crete, ” Highway Research Record No. 80, Highway Research Board, 1965,pp. 57-73.

7. Kozlov, George S., “Preformed Elastomeric Bridge Joint Sealers,”Highway Research Record No. 200, Highway Research Board, 1967, pp.36-52.

8. Panek, Julian R., and Cook, John P., Construction Sealants and Ad-hesives, 2nd Edition, John Wiley & Sons, New York, 1984.

9. Klosowski, Jerome M., Sealants in Construction, Marcel Dekker,Inc., New York.


APPENDIX A-LAYMAN’S GLOSSARY FORJOINT SEALANT TERMS

This glossary is based on the terminology used orproposed by ASTM and ISO committees or commontrade parlance. The definitions are not definitive andare prepared for the purpose of understanding thisguide only.

Accelerator*- A compounding ingredient used insmall amounts with a curing agent to increase the speedof vulcanization and/or enhance the physical propertiesof the vulcanizate.

Adhesion-The state in which two surfaces are heldtogether by interfacial forces.

Adhesive-A substance having the capability of main-taining surface attachment by interfacial forces be-tween two or more surfaces.

Anti-foaming agent-Product which greatly increasesthe surface tension, thereby reducing the tendency tofoam during mixing or application.

Antioxidant-Compounding ingredient used to retarddeterioration caused by oxidation.

Applied skin-A thin surface layer of elastomericmaterial applied to a cellular product.

Backup-A compressible material used in the bottomof sealant reservoirs to reduce the depth of the sealantthus improving its shape factor. Also serves to supportthe sealant against sag or indentation.

Bleeding*-Exudation with possible absorption byporous surfaces of a component of a sealant.

Blister-A cavity or sac that deforms the surface ofa material.

Blowing agent-Compounding ingredient used to pro-duce gas by chemical and/or thermal action in manu-facture of hollow or cellular articles.

Bond breaker*-Material used to prevent a sealantbonding undesirably to the bottom of a joint; or tofacilitate independent movement between two unitsthat would otherwise behave monolithically.

Bond face-That part of the joint face to which afield-molded sealant is bonded.

Butt joint*-A joint in which the structural unitsbeing joined abut each other so that under movementany sealant is in tension or compression between thejoint faces.

Catalyst * -Substance added in small quantities topromote reaction between two other substances whileitself remaining unchanged.

Cellular material-A generic term for material con-taining many cells (either open, closed, or both) dis-persed throughout the mass.

Chemical cure-Curing (hardening) by chemical re-actions usually involving the formation of cross linkedpolymers.

Closed cell-A cell totally enclosed by its walls andhence not interconnecting with other cells.

Cohesion-The form of attraction by which the bodyof an adhesive or sealant is held together. The internalstrength of an ahdesive or a sealant.

Compound-An intimate admixture of a polymerwith all the ingredients necessary for the finishedarticle.

Compression seal -A compartmentalized or cellularsealant which by compression between the joint facesprovides a seal.

Conventional rubber cure-See vulcanization.Copolymer-Large molecule resulting from simul-

taneous polymerization of different monomers; morecommonly, the compound consisting of such molecules.

Cross linked-Molecules of a polymer that are joinedside by side as well as end to end.

Cure-To set up or harden through change in thephysical properties of a plastic, resin or polymer bychemical reaction.

Curing agent-Catalyst or hardener.Diluent* -Liquid which lowers viscosity and in-

creases the bulk but is not necessarily a solvent forthe solid ingredients; a thinner.

Drier* -Chemical which promotes oxidation ordrying.

Effective length-The length of that section of astructural unit which is free to move toward or awayfrom a joint.

Elastomer-Macromolecular material that returnsrapidly to approximately the initial dimensions andshape after substantial deformation by a weak stressand release of the stress.

Elastomeric-Having the attributes of an elastomer.Emulsion*-Water system containing dispersed col-

loidal resin or liquid particles.Expansion-compression-The percentage increase and

decrease in width from the installed width tolerable toa sealant in service.

Extender* -An organic material (usually cheaper)used as a replacement for a portion of the materialrequired in a sealant compound.

Extensibility* - T h e capacity of a sealant to bestretched in tension.

Field-molded sealant-A liquid or semi-solid mate-rial molded into the desired shape in the joint intowhich it is installed.

Filler*-(a) Finely divided material compounded insealant to give body. (b) Compressible, preformed ma-terial used between the faces of an expansion joint toform or maintain the space between them.

Gasket-A deformable material clamped between es-sentially stationary faces to prevent the passage ofmatter through an opening or joint.

Hardener*- Substance which enters into chemicalcombination with other substances to form a new,more solid material.

Hardness-The property of resisting identation. Note:When hardness is expressed as a number, the numberhas no quantitative meaning, except in terms of a par-ticular test in which the size and shape of the indenter,the indenting load, and other conditions of the test arespecified.

Hump-See sag. Sealant is, however, raised ratherthan depressed.

Joint-The interstice between component parts orunits.

Joint movement (total)-The difference in width of ajoint opening between the fully open and fully closedpositions.

Lap joint-A joint in which the structural units beingjoined override each other so that under movementany sealant is in shear between the joint faces.

*Terms designated by asterisk differ in some way from defini-tion given in ACI Committee 116, Cement and Concrete Termi-nology (ACI Publication SP-19).

APPENDICES


Low temperature recovery-Ability of a sealant torecover its original form at low temperature when thedeforming load is removed.

Mastic-A sealant with putty-like properties.Migration-Spreading or creeping of sealant vehicle

onto adjacent surfaces usually to the detriment of bond.Monomer-A composition of single molecules; a

basic chemical used to make polymers.Necking-An irrecoverable reduction in cross section

of a sealant under stress.Non-staining-Unable to stain or discolor adjacent

surfaces (see stain).O-ring-An elastomeric seal of homogeneous com-

position molded in once piece to the configuration of atorus with circular cross section.

Open cell-A cell not totally enclosed by its wallsand hence interconnecting with other cells or with theexterior.

Packing-A deformable material used to prevent orcontrol the passage of matter between surfaces whichmove in relation to each other.

Peeling*-Local pulling away or curling of the seal-ant from its substate at points of stress concentrationsuch as corners, edges or bubbles.

Pick-up-Unwanted adherence of solids in contactwith the open surface of a sealant, i.e., adherence ofsealant to tires.

Permissible movement-The safe joint movementwhich can take place without failing the sealant.

Polymer* A compound formed by the reaction ofsimple molecules having functional groups which per-mit their combination to proceed to high molecularweights under suitable conditions.

Positive anchor-Point of intentional restraint againstmovement.

Pot life-(Sometimes referred to as “work life”)-Time interval after mixing during which liquid materialis usable with no difficulty.

Preformed sealant-Sealant functionally preshapedby the manufacturer so that only a minimum of fieldfabrication is required prior to installation.

Pressure sensitive-Capable of adhering to a surfacewhen pressed against it.

Primer-A material applied to joint faces to improvethe bond (adhesion) of field-molded sealants.

Reinforcing agent-An ingredient used in rubber toincrease its resistance to destructive mechanical forces,e.g., resistance to abrasion, rupture, tear, etc.

Retarder*-Compounding ingredient used to reducethe tendency of a mix to vulcanize prematurely.

Reversion-Chemical reaction leading to sealant,back-up or filler deterioration due to moisture trappedbehind the sealant.

Rubber-A material that is capable of recoveringfrom large deformations quickly and forcibly.

Rubber latex-Colloidal aqueous emulsion of anelastomer.

Sag-Sealant flow within the joint so that it loses itsoriginal shape, usually becoming depressed in hori-zontal joints or alternately bunched and attenuated invertical joints.

Seal-A generic term for any material or device thatprevents or controls the passage of matter across theseparable members of a mechanical assembly.

Sealant-Any material used to seal joints or openingsagainst the passage of solids, liquids or gases.

Set: (compression), (tension) or (permanent)*-The change occurring in a sealant when deformedthat prevents full recovery when the deformation ends.More correctly, the strain remaining after completerelease of the load producing deformation.

Shape factor- The relationship between depth andwidth of a field-molded sealant.

Shelf life*-Maximum length of time a sealant canbe stored prior to use without adversely affecting itsproperties.

Skin-A relatively dense layer that forms at thesurface of a sealant on exposure to air.

Solvent-Liquid in which another substance may bedissolved.

Sponge-Cellular version, consisting predominantlyof open cells, of a solid material.

Stabilizer-Substance which makes a solution orsuspension more stable, usually by keeping particlesfrom precipitating.

Stain-The changed color or appearance of the sur-face of the substrate adjacent to an applied sealant;the change is usually penetrating and the coloring istransparent and without surface film.

Stock-The shape in which preformed materials aresupplied.

Stress relaxation* -Reduction in stress due to creepunder sustained strain (deformation).

Structural unit-That part abutting a joint between itand another part which may have a similar or dis-similar structural function.

Substrate-The surface to which a sealant must bond(or remain in contact) usually the joint face.

Swelling*-The increase in volume or linear dimen-sions of a specimen immersed in a liquid or exposedto a vapor.

Tack-free time-Measure of the period for which afield-molded sealant remains tacky and not yet fullyserviceable with respect to pick-up.

Tear strength-The maximum force required to tearapart a specified specimen, acting substantially paral-lel to the major axis of the test specimen.

Thermoplastic*-Mobile; softening with heat.Thermosetting-Becoming rigid by chemical reaction

and not remeltable.Vehicle*-Liquid carrier; binder (anything dissolved

in the liquid portion of the sealant is a part of thevehicle).

Volatile-Evaporating readily.Vulcanization-A process in which rubber through a

change in its chemical structure (e.g., cross-linking) isconverted to a condition in which the elastic propertiesare conferred or improved.

Waterstop* -Diaphragm used across a joint as asealant, usually to prevent the passage of water.

Work(ing) life-See pot lifeWrinkling-Crinkling of the surface skin of sealants

affecting appearance, but not usually affecting sealingcapability.

504R-40

ACI COMMlTTEE REPORT

.” .,t . .

. . :: .: I. I, ::

;‘_. ..‘.

.a.. ‘,_.....El.........

: .,: .........

.......... -*......L.

: .: & ::. ..

...

APPENDIX B-KEY TO SYMBOLS USED IN FIGURES

Sealant (general) - - - - Tie bars across joint

Specifically a compression seal Crack

Bonded concrete surface

Filler-compressible

Exposure from this direction

Back-up material

-I _+ Movement opening joint

Mortar filler, bedding or grout-not compressible

,[_ Movement closing joint

l 2 l Waterstop

Ground line

l oooo Bond breaker (Also intentionally non-bonded Keywayconcrete surfaces)

1ST2NDETC.

Sequence of placing concrete Wood or other forms

W Joint width (general) Wmin Joint width when closed (usually at 130F (54C)

Wi Joint width at installation of sealant d Depth of sealant (general)

Wmax Joint width when open (usually at -2OF dmax Maximum depth of sealant a t instal la t ion(-29C) width Wi to provide required shape factor

APPENDIX C-SOURCES OF SPECIFICATIONS

NUMBER AND TITLE DESCRIPTION-USE-REQUIREMENTS NUMBER AND TITLE DESCRIPTION-USE-REQUIREMENTS

I. FIELD-MOLDED SEALANTS

AMERICAN SOCIETY FOR TESTING & MATERIALS SPECIFICATIONS

(1)

(2)

(3)

(4)

(5)

(6)

(7)

ASTM C 920-87Specification for ElastomericJoint Sealants

For single or multi-component cold applied materials, used in building constructionother than highways, air fields and bridges

ASTM D 1190-80 (1980)Concrete Joint Sealer,Poured Elastic Type

Hot

ASTM D 1854-74 (1985)Jet Fuel-Resistant Hot-PouredElastic Type

ASTM D 3405-78Joint Sealants, Hot-Poured forConcrete and Asphalt Pave-ments

ASTM D 3406-85Specification for Joint Sealant,Hot-Applied, Elastomeric-Typefor Portland Cement ConcretePavements

ASTM D 3569-85Specification for Joint SealantHot-Poured Elastomeric Type,Jet Fuel Resistant for PCC Air-field Pavements

ASTM D 3581-80 (1985)Soecification for Joint SealantHot Poured, Jet Fuel ResistantType for Portland Cement~~m~~sand Tar Concrete

No specific material; mixture type forming a resilient sealant, forbridges, etc. Tests include pour point, penetration, flow, and bond.

use in pavement,

No specific material; composed of mixture of materials forming a resilient sealant foruse in concrete pavements exposed to jet fuel spillage and jet blasts. Tests includepenetration, bond, and safe heating temperature.

No specific material. Tests include penetration, flow, bond, and resilience.

PVC-coal tar; for use in PCC pavement, bridges, etc. Tests include penetration, flow,bond, resilience, tensile adhesion, and artificial weathering.

PVC-coal tar, for use in PCC airfield pavements subject to jet fuel spillage and jet blast.Tests include penetration flow, bond, resilience, tensile adhesion, artificial weathering,and jet fuel solubility.

For single or multicomponent hot applied materials, checks fuel resistance.

OFFICIALS SPECIFICATIONS

(8) Ml 73-60Hot Poured Elastic Type

FEDERAL SPECIFICATIONS

Same description, use, and requirements as in ASTM D 1190-74 (1980).

(9)

WV

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SS-S-1401 C, 8/l 5184Sealing Compound, Hot-Ap-plied, for Concrete AsphaltPavements

SS-S-1614A, 8/l 5184Sealant, Joint Jet-Fuel Re-sistant, Hot-Applied, for Port-land Cement and Tar ConcretePavements.

SS-S-POOE Amended 8123188Sealant, Joint, Two-Compo-nent, Jet-Blast Resistant,Cold-Applied, Concrete Paving

;;;V;0227E (COM-NBS)

Sealing Compound, Elas-tomeric Tynent (For e

e, Multi-Compo-aulking, Sealing,

and Glazing in Buildings andOther Structures)

~-lLSIO23Oc (COM-NBS)

Sealing Corn ound, Elas-tomeric Type, 8ingle Compo-nent, (For Caulking, Sealing,and Glazing in Burldings andOther Structures)

No specific material; mixture of materials which form a resilient and adhesive com-pound. It will not flow from the joint or be picked up by tires at temperatures up to 125F(51.7C). Tests include safe heating temperature, penetration, flow, resilience, bond, andcompatibility.

No specific material; mixture of materials which form a resilient and adhesive compoundresistant to jet fuel. Pourin temperature not over 450F (232.2C). Shall not be picked upby tires at 125F (51.7C). Qests include penetration solubility, flow, and fuel-immersedbond strength. The compound may be furnished as a solid or a liquid, both requiringfield heating.

Material shall be two-component elastomeric type consisting of base and activatorforming a rubberlike compound after mixing. Rate of curin shall permit traffic withinone hour after curing. Material shall be resistant to jet fuel. 9ests include tackfree time,ball penetration, resilience, bond, flow, self-leveling, weathering, solubility, volumechange, and flame resistance.

Covers multicomponent cold-applied elastomeric joint sealant. Two types: I, Flow, self-leveling; and II, Non-sag. Class A compounds resistant to 50 percent maximum totaljoint movement, Class B to 25 percent maximum. Tests include compression-extensioncycling at 158F (70C) and 15F (9X) with glass, aluminum, and concrete, peelstrength, stain, and others.

Covers elastomeric polymer type sealant for use without mixing. Types, classes, andrequirements essentially the same as in TT-S00227e. Some formulations require sev-eral weeks to reach full cure in the joint.

P?R

6

NUMBER AND TITLE DESCRIPTION-USE-REQUIREMENTSNUMBER AND TITLE DESCRIPTION-USE-REQUIREMENTS

(14) ;;T=&OO1543a (COWNBS)

Sealing Compound: SiliconeRubber Base (For Caulking,Sealing and Glazing in Build-ings and Other Structures)

Material is a single component cold-applied silicone rubber base sealing compound(joint sealants) for sealing, caulking, and glazing in building construction. Test require-ments are essentially the same as (15) except that extrusion at -15F (9.4C) is requiredand no water immersion test is required for porous masonry.

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1%GP-17MSealing Compound, One Com-ponent, Acrylic Emulsion Base

This standard applies to one-component acrylic water emulsion sealing compoundssuitable for sealing, caulking, or glazing interior building joints that experience up to+ 10%. The substrates may be concrete, glass, wood, or metal. Materials meeting thisstandard are not intended for use in experience continous water immersion nor forexterior building joints.

This standard applies to one-component silicone rubber based joint sealing com-

gounds that cure primarily by solvent evaporation intended for sealing interior or exterior

uilding joints that have movements up to +25% movement with an application airtemperature range of 5 to 30C (41 to 86F). Materials meeting this standard are notintended for traff ic or continuous water immersion conditions.

(15) mS-001657 10/8/70Sealing Compound-SingleComponent

Butyl rubber based, solvent release type (for buildings and other types of construction). Sealing Compound, One Com-ponent, Silicone Base, SolventCuring

CANXGSB-19.2~M87 This standard applies to cold-applies jet fuel-resistant sealing compounds intended forCold-Applied Sealing Com- sealing joints in portland cement concrete pavements where the air application tem-pound, Aviation Fuel-Resistant perature is between 4 and 35C (39 to 95F).CANADIAN GENERAL STANDARDS BOARD

CANEGSB-19.21 -M87Sealing and Bedding Com-pound, Acoustical

This standard applies to acoustical sealing and bedding compounds suitable for sealinginterior building joints that experience up to +5% movement and the application airtemperature range is between 5 to 30C (41 to 86F). The substrates may be concrete,masonry, metal, gypsum-board, plaster, or wood.

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CANEGSB-19.0-M77Methods of Testing Putty,C$.u.ul~~g and Sealing Com-

This document contains general physical and chemical methods of testing putty, caulk-ing and sealant compounds for conformance with the standards of the Canadian Gen-eral Standards Board. The intent is to provide a uniform basis for testing proceduresand eliminate variations in methods used.

CANEGSB-19.24-M80Sealing Compound, Multi-Component, Chemical Curing

This standard applies to two types (self-leveling and nonsag) and two classes (glazingand nonglazing) of multi-component joint sealing compounds that cure to a rubber-likesolid when properly mixed. Materials meeting this standard are intended for sealing orcaulking exterior or interior building joints that have movements up to + 25% and maybe used on concrete, masonry, metal, glass (class I only) or wood.

CAN(CGSB)-19.1 -M87Putty, Lrnseed Oil Type

This standard aglazing of wooc!

plies to two types of putty which are intended for exterior or interiorsash and should be used where the application air temperature is

between 4 and 27C (39 to 80F). It’s not intended to fill nail holes nor to be used wherejoint movement is anticipated.

CANICGSB-19.2-M87Glazing Compound, Nonhard-ening, Modified Oil Type

This standard applies to compounds suitable for glazing exterior or interior buildingsashes where the substrate is wood or metal. Materials meeting this standard areintended for face and channel glazing and in areas subject to vibration where only asmall amount of movement is anticipated. The application air temperature range isbetween 4 to 27C (39 to 80F). Materials are not intended to be used on poroussubstrates.

AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIFICATIONS

ASTM D 2628-81 Material shall be preformed and manufactured from vulcanized elastomeric compoundusing polychloroprene as the only base polymer. Tests include tensile strength, elonga-tion, hardness, oil swell, ozone resistance, low and high temperature recoveries.

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Specification for PreformedPolychloroprene ElastomericJoint Seals for Concrete Pave-ments

19-G P-5MSealing Compound, One Com-ponent Acrylic Gas, SolventCuring

This standard is for materials that are one-component, acrylic polymer based sealantsthat cure essentially by solvent evaporation. Used for sealing or glazing exterior orinterior joints in buildings where the substrate(s) is glass, metal, masonry or wood withmovements up to + 7%. Materials meeting this standard are not suited for traffic areas,or continuous prolonged water immersion as with horizontal deck joints. Tests includeweight loss, sag, hardness, staining and low-temperature flexibility. ASTM D 3542-85

Specification for PreformedPolychloroprene ElastomericJoint Seals for ConcreteBridges

Material shall be preformed and manufactured from vulcanized elastomeric compoundusing polychloroprene as the only base polymer. Tests include tensile strength, elonga-tion, hardness, oil swell, ozone resistance, low and high temperature recoveries, andmovement calibration.

CANICGSB-19-M87Caulking Compound Oil Base

This standard applies to two types of one-component oil-based solvent-release jointsealing compounds. Used for sealing interior or exterior building joints in wood ormasonry where the total expected movement is 2%. The temperature application rangeis 4C to 27C. Not intended for joints subject to traffic areas or immersion conditions.

ASTM D 994-71 (1982Specification for f’Pre ormedExpansion Joint Filler for Con-crete (Bituminous Type)

Material consists of bituminous mastic formed and encased between two layers ofbituminous impregnated felt. Mastic comprises mineral distortion, brittleness, waterabsorption, and compression.

CANICGSB-19.13-M87Sealing Compound, One Com-ponent, Elastomeric Chem-ically Curing

This standard applies to one-component materials that cureare suitable for sealing, caulking, or glazing applications.

to rubber-like solids and

ASTM D 1751-83Specification for PreformedExpansion Joint Filler for Con-crete Paving and StructuralConstruction (Nonextrudingand Resil ient BituminousTypes)

Material consists of preformed strips formed from cane or other cellular fibers which arebound together and saturated with bituminous binder, or strips formed from granulatedcork bound with bituminous material and encased between layers of bituminous felt.Tests include compression, extrusion, recovery, water absorption, weathering, andothers.

19-GP-14Sealina Comoound. One Com-ponent Butyl-PolyisobutylenePolymer Base, Solvent Curing

This standard applies to one-component solvent release butyl-polyisobutylene jointsealingjoints th

compounds suitable for sealing, caulkingat experience up to + 5% movements. Th

or glazing interior or exterior buildine substrated may be masonry, Bmeta ,

wood or glass. Materials meeting this standard are not suited for joints in traffic areas orwill experience continuous water immersion.

NUMBER AND TITLE DESCRIPTION-USE-REQUIREMENTScNUMBER AND TITLE DESCRIPTION-USE-REQUIREMENTS

Three types for use in concrete, brick, and stone: Type I, sponge rubber; Type II, cork;Type Ill, Self-expanding cork. Tests include compression, extrusion, expansion, re-sistance to acid, density, and weathering.

U.S. FEDERAL SPECIFICATIONS

(40) HH-F-341 F, 6/6/77Fillers. Exoansion Joint: Bi-tuminous (Asphalt and Tar)and Nonbituminous (Pre-formed for Concrete)

(41) HH-P-1 19a, 2/l 6167Packing Material, Sewer Joint,Asphalt Saturated CelluloseFiber

U.S. ARMY CORPS OF ENGINEER

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ASTM D 1752-84Specification for PreformedSponge Rubber and Cork Ex-pansion Joint Fillers for Con-crete Paving and StructuralConstruction (Nonextrudingand Resilient NonbituminousTypes [Similar to (34) below.])

Three types: I, bituminous fiber or bituminous cork -nonextruding and resilient; II,nonbituminous. Type II covers Class A, sponge rubber; Class B, cork; Class C, self-expanding cork; Ill, plain bituminous (encased asphalt or tar), nonresilient. Materialshall have little extrusion and sufficient recovery after compression. Tests include recov-ery, compression, extrusion, insolubility, etc.

Material consists of preformed shapes for gaskets and seals in building applicationsincluding glazing. Four rades are included depending on degree of firmness. Testsinclude compression-deflection stress relaxation, dimension stability, and low tem-

ASTM C 509-84Specification for Cellular Elas-tomeric Preformed Gasket and

Material shall be rope-like, asphalt impregnated cellulose-fiber packing for use betweenbells and spigots of sewer pipe prior to filling with bituminous cold-applied sealingcompound. Sizes range from 3/8 to 1 -l/2 in. (9.5 to 31.7 mm) in diameter. Tests include

8 resistance to acids K8H and H2S, and flexibility.Sealing Material perature brittleness.

SPECIFICATIONConsists of elastomeric material resistant to sunlight, weathering, flame, oxidation,permanent deformation and diminution of gripping pressure. Gaskets are generallyknown as “zipper type.” Tests include tensile strength hardness, compression set,ozone resistance.

ASTY .C 542-82 (1964);g;;rf;atron for Lock Strip

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cm-c 513-74Specifications for Rubber Wa-terstops

Covers waterstop of dimensions to be given elsewhere, made of natural or syntheticrubber or a blend. Samples from each 200 ft. (61 m) to be tested for tensile strength andelongation; other tests to be made on samples from the lot for hardness, stress for 300percent elongation, water absorption, compression set, strength after oxygen aging,and ozone cracking resistance.STATE HIGHWAY AND TRANSPORTATIONAMERICAN ASSOCIATION OF

OFFICIALS SPECIFICATIONS

Material shall be extruded from an elastomeric plastic compound, the basic resin ofwhich shall be polyvinylchloride. Tests include tensile strength, elon ation, low tem-perature brittleness, stiffness in flexure, accelerated extraction, and ewect of alkalies.

CRD-C 572-74Spec i f i ca t ions fo r Poly-vinylchloride WaterstopsMaterial shall be tar or asphalt impregnated with suitable filler to reduce brittleness at

low temperatures. Tests for absorption, distortion, brittleness, and compression. (Sameas ASTM D 994-71 (1982)

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M-33-81Preformed Expansion JointFiller for Concrete (BituminousType)

CRPC 527-88Specification for Joint Seal-ants, Cold Applied, Non-Jet-Fuel-Resistant, for Rigid andFlexible Pavements

Covers one and two-part formulations (Silicones and non-silicones) with acidic curingproducts not allowed. Test include application, leveling, change in volume, swelling, tackfree time, compatibility with bitumen, flow, penetration, and bond to Portland-CementConcrete.

Material shall be mixture of asphalt, fiber, and mineral ag regate formed by extrusionunder pressure. Two types, (a) plain asphalt plank, and b) mineral-surfaced asphalt?plank. Tests include absorption, brittleness, and indentation.

M-48-70 (1982)Asphalt Plank

CRD-C 548-88Specification for Jet Fuel andHeat Resistant PreformedPolychloroprene ElastomericJoint Seals for Rigid Pave-ments

Material shall be preformed and manufactured from vulcanized elastomeric compoundusing polychloroprene as the only base polymer. Tests include jet-fuel and heatresistance.

M-l 53-84Preformed Sponge Rubberand Cork Fillers for ConcretePaving and Structural Con-struction

Covers three types of fillers for use in concrete, brick or stone construction: I, spongerubber; II, cork; Ill, self-expanding cork. Tests include recovery, compression, extrusion,expansion, boiling in hydrochloride acid, density, and weathering. (Same as ASTM D1752-67 (1978).

ONTARIO HYDRO

(46) M-264-M-83Polyvinylchloride Waterstop

This specification covers preformed elastic joint seals of the open cell compressiontype, also covers lubricant adhesive.

M-220-1 985Preformed Elastomeric Com-pression Joint Seals Material shall be preformed from reworked and virgin polyvinylchloride. Shapes and

dimensions for flat-ribbed waterstops and premolded junctions are specified. Testsinclude tensile strength, elongation, tear, effect of alkalies, impact, low temperaturebrittleness.

Material consists of preformed strips formed from cane or other cellular fibers which arebound together and saturated with bituminous binders; or strips formed from granulatedcork found with bituminous material and encased between layers of bituminous felt.Tests include compression, extrusion, recovery, water absorption, weathering, and oth-ers.

M-21 3-81Preformed Expansion JointFillers for Concrete Pavin andStructural Construction 9Non-extruding and Resilient Bi-tuminous Types)

Synthetic rubbers and blends. Test include tensile strength, elongation, hardness, com-pression set, rear, ozone radiation pressure, water absorption, resistance, effects ofalkalies, low and high temperature. A guide to installation is provided in InstructionManual L-l 66 for these waterstops.

(47) L-l 219-88Standard Specification for Wa-terstop (Styrene ButadieneRubber)


SOURCES OF SPECIFICATIONSThe specifications listed were the latest editions at the time this report

was prepared. Since these specifications are revised frequently, gener-ally in minor details only, the user should check directly with the spon-soring society if it is desired to refer to the latest edition.

Information regarding the availability of the specifications listed canbe obtained from the agencies below.

ASTM SpecificationsAmerican Society for Testing and Materials1916 Race St.Philadelphia, Penn. 19103

AASHTO SpecificationsAmerican Association of State Highway and

Transportation Officials444 N. Capitol St., N.W. Suite 225Washington, D.C. 20001

Federal Speficiations

Business Service CenterGeneral Services Administration7th and D Streets SWWashington, D.C. 20407

Military SpecificationsCommanding OfficerNaval Publications and Forms Center5801 Tabor AvenuePhiladelphia, Pa. 19120

ANSI SpecificationsAmerican National Standards Institute, Inc.1430 BroadwayNew York, N.Y. 10018

U.S. Army Corps of EngineersChief, Concrete Laboratory, WESBox 631Vicksburg, Miss. 39180

Canadian General Standards

SecretaryCanadian General Standards BoardPhase III9C1 Place du PortageHull, Quebec KlA OS5

Ontario HydroDirector of Research800 Kipling Avenue S.Toronto, Ontario M8Z 5B2Canada

This report was submitted to letter ballot of the committeeproved in accordance with ACI balloting procedures.

and was ap-

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