fernando schnaid - antonino di...
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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
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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
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5
10
15
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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
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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
