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Dilatometer test

Fernando SchnaidUniversidade Federal do Rio Grande do Sul, Brasil

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STANDARDS

Eurocode 7 (1997). Geotechnical design - Part 3: Design assisted by field testing, Section 9: Flat dilatometer test (DMT).

ASTM D 6635-01 (2001). "Standard Test Method for Performing the Flat Plate Dilatometer ".

MANUALS

Marchetti, S. & Crapps, D.K. (1981). "Flat Dilatometer Manual". Internal Report of G.P.E.

Schmertmann, J.H. (1988). Rept. No. FHWA-PA-87-022+84-24 to PennDOT, Office of Research and Special Studies, Harrisburg, PA, in 4 volumes.

US DOT - Briaud, J.L. & Miran, J. (1992). "The Flat Dilatometer Test". Dept. Transp., Fed. Highway Adm., Washington, D.C., FHWA-SA-91-044, 102 pp.

ISSMGE TC16 (2001): DMT in Soil Investigations

DMT on the INTERNET

Bibliographic site <www.marchetti-dmt.it> download papers

Basic reference

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DMT: LAYOUT

Slides:courtesy from Silvano Marchetti

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PenetrationDMT USING APENETROMETER

DMT USING ADRILL RIG

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6

7

8Dilatômetro sísmico

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Measurements and parameters

A- pressure: “lift-off”pressure – membrane starts to expand

B- pressure: 1,1 mm movement of centre of membrane

C-pressure: closing pressure (≈ uo)

Calibration in arΔA = external pressure to be applied to membrane

ΔB = internal pressure required to move 1,1 mm

( ) ( )BZBAZAp mm Δ−−−Δ+−= 05.005.10

( )BZBp m Δ−−=1

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Measurements and parameters

a) Material Index: ID

b) Horizontal stress index: KD

c) Dilatometer modulus ED

'vo

ooD

upKσ−

=

( )oD ppE −= 17.34

oo

oD up

ppI−−

= 1

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Typical results

• Id : soil type • Courtesy from Marchetti

Obs :Kd = 2 →OCR ≈ 1

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Typical results: seismic

Courtesy from Marchetti

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Repeatability Cestari (SGI), Lacasse (NGI), Lunne (NGI), Marchetti (Aq)

NC clay Onsoy, Norway

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InterpretationMarchetti, 1981From A, B (p0, p1) :

Kd : an amplified Ko

Theory of elasticity

Rm=f(Kd,Id)Distortion, Horiz to VertDrained-undrained

Undrained shear strength

after Powell & Uglow, 1988after Powell & Uglow, 1988

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DMT: NC Clay

Cu in Tokyo Bay Clay

Geotechnical Research Center Kiso-Jiban Consultants Co., Tokyo

Iwasaki K., Tsuchiya H., Sakai Y., Yamamoto Y. (1991). "Applicability of the Marchetti Dilatometer Test to Soft Ground in Japan", GEOCOAST '91, Sept. 1991, Yokohama 1/6

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Cu: Skeena Ontario Canada

Vs Field Vane

Mekechuk J. (1983). "DMT Use on C.N. Rail Line British Columbia",First Int.Conf. on the Flat Dilatometer, Edmonton, Canada, Feb 83, 50

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Cu: National Site BOTHKENNAR UK

Nash et al., Géotechnique, June 1995, p. 173

0

5

10

15

20

Z (m

)

kPa

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Cu: National Site FUCINO

Note the various Nc for CPT(U)A.G.I., 10th ECSMFE Firenze 1991, Vol. 1, p. 37

Z (m

)

kPa

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Cu: 2 Malaysian Clays

Vs Field Vane

Wong, J.T.F. & Dobie, M.J.D. 1990. Marchetti Dilatometer: Interpretation in Malaysian Alluvial Clays. Seminar on Geotechn. Aspects of the North-South Expressway, 5-6th Nov, pp. 87-96.

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Cu: Recife

Coutinho et al., Atlanta ISC'98

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OCR

Kamei T. and Iwasaki K. (1995). "Evaluation of Undrained shear strenght of cohesive soils using a flat dilatometer"

NoteMarchetti (1980) original: OK

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OCR

FEM, Yu (2004)FEM, Yu (2004)

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M: ONSOY Clay (NORWAY)

Norwegian Geotechnical Institute (1986). "In Situ Site Investigation Techniques and interpretation for offshore practice". Report 40019-28 by S. Lacasse, Fig. 16a, 8 Sept 86

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M: Tokyo Bay Clay

Geotechnical Research CenterKiso-Jiban Consultants Co., Tokyo

Iwasaki K, Tsuchiya H., Sakai Y., Yamamoto Y. (1991) "Applicability of the Marchetti Dilatometer Test to Soft Ground in Japan", GEOCOAST '91, Sept. 1991, Yokohama 1/6

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M: Bangkok Clay

Seah and Rasheed – unpublished results

SIMILAR CONCLUSIONS for MGenerally satisfactory for everyday practice, w/o local correlations (clay)

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DILATOMETRO SÍSMICO (SDMT)

ALTERNATIVAS

2 sensores

Amplificador

Independe do operatodor

SDMT S - DMT

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Seismic Dilatometer (SDMT)Seismic Dilatometer (SDMT)

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SDMT at Fucino (June 2004)

AS RECORDED RE-PHASED

9 m

10 m

11 m

12 m

13 m

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Comparison with other techniques (after Merchetti, 2006)

0

5

10

15

20

25

30

35

40

0 100 200 300 400Vs (m/s)

Z (m

)

SDMT P.I.

SDMT T.I.

SCPT P.I.

Fucino Research Site Venezia - Treporti

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G - γ curve

HARA (1973)

YOKOTA et al. (1981)

TATSUOKA (1977)

SEED & IDRISS (1970)

ATHANASOPOULOS (1995)

CARRUBBA, MAUGERI (1988)

MAUGERIS. Louis 1995

0.05 to 0.1%

Telespazio

Fucino Centro Telespazio, Marchetti (2006)

Zelazny Most, Poland, Marchetti (2006)

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Final comments

Validation is restricted to sedimentary depositsCimentation effects not known (structuration and destructuration)Empirical approaches will preveil

Easy to used deviceUsed worldwide

Grazie tanto

Muito obrigado

www.cesup.ufrgs.br/fernandofernando@ufrgs.br