Determination of the material damping ratio and the shear wave velocity with the Seismic Cone Penetration Test

The downhole seismic cone penetration test (SCPT) procedure has been extended to allow the measurement of material damping at small strains at minimum expense while one is measuring shear wave velocity. The nature of damping, the required equipment characteristics, and the recommended procedure and calculation methodology are presented in a practical way. SCPT results from four different sites give results that are in general agreement with laboratory measurements of damping for sands and clays and with values recommended by other authors. It appears, however, that previously reported measurements of damping by borehole methods are higher, by a factor of two or more, when compared with SCPT and laboratory results. Key words : in situ, damping, seismic, shear wave, cone penetrometers, procedures.

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Development of an empirical correlation for predicting shear wave velocity of Christchurch soils from cone penetration test data

Soil Dynamics and Earthquake Engineering ◽

10.1016/j.soildyn.2015.03.023 ◽

2015 ◽

Vol 75 ◽

pp. 66-75 ◽

Cited By ~ 24

Author(s):

Christopher R. McGann ◽

Brendon A. Bradley ◽

Merrick L. Taylor ◽

Liam M. Wotherspoon ◽

Misko Cubrinovski

Keyword(s):

Shear Wave ◽

Wave Velocity ◽

Test Data ◽

Shear Wave Velocity ◽

Cone Penetration Test ◽

Empirical Correlation ◽

Penetration Test ◽

Cone Penetration

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Seismic cone penetration test for evaluating liquefaction potential under cyclic loading

Canadian Geotechnical Journal ◽

10.1139/t92-075 ◽

1992 ◽

Vol 29 (4) ◽

pp. 686-695 ◽

Cited By ~ 122

Author(s):

P. K. Robertson ◽

D. J. Woeller ◽

W. D. L. Finn

Keyword(s):

Cyclic Loading ◽

Shear Wave ◽

Wave Velocity ◽

Shear Wave Velocity ◽

Penetration Resistance ◽

Penetration Test ◽

Cone Penetration ◽

Liquefaction Potential ◽

A Site ◽

Seismic Cone Penetration Test

Impressive progress has been made in the last 25 years in recognizing liquefaction hazards, understanding liquefaction phenomena, and analyzing and evaluating the potential for liquefaction at a site. Recent findings related to the application of the seismic cone penetration test (SCPT) for the evaluation of liquefaction potential under cyclic loading are presented and discussed. The SCPT provides independent measurements of penetration resistance, pore pressures, and shear-wave velocity in a fast, continuous, and economic manner. The current methods available for evaluating liquefaction using penetration resistance are presented and discussed. Recent developments in the application of shear-wave velocity to evaluate liquefaction potential are discussed, and a new method based on normalized shear-wave velocity is proposed. Limited case-history data are used to evaluate and support the proposed correlation. A worked example is presented to illustrate the potential usefulness of the SCPT for evaluating liquefaction potential at a site. Key words : liquefaction, in situ tests, seismic.

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Characterization of Norwegian marine clays with combined shear wave velocity and piezocone cone penetration test (CPTU) data

Canadian Geotechnical Journal ◽

10.1139/t09-133 ◽

2010 ◽

Vol 47 (7) ◽

pp. 709-718 ◽

Cited By ~ 32

Author(s):

Michael Long ◽

Shane Donohue

Keyword(s):

Shear Wave ◽

Wave Velocity ◽

Shear Wave Velocity ◽

Small Strain ◽

Cone Penetration Test ◽

Research Quality ◽

Penetration Test ◽

Cone Penetration ◽

Tip Resistance ◽

Marine Clays

A database of research-quality piezocone cone penetration test (CPTU) and shear wave velocity, Vs, information for Norwegian marine clays has been assembled to study the small-strain stiffness relationships for these materials and to examine the potential use of CPTU and Vs data in combination for the purposes of characterizing these soils. Data for sites where high-quality block sampling was carried out have mostly been used. Improvements have been suggested to existing correlations between the small-strain shear modulus, Gmax, or Vs and index properties for these soils. Recent research has shown that CPTU corrected cone tip resistance, qt, and especially the pore pressure measured during CPTUs, u2, and Vs can be measured reliably and repeatably and are not operator or equipment dependant. Therefore, a new soil classification chart involving the normalized cone resistance, Qt, and normalized shear wave velocity, Vs1, or Vs1 and Δu/[Formula: see text] (where u is the pore-water pressure and [Formula: see text] is the in situ vertical effective stress) is presented. Using this chart it is possible to clearly distinguish between clays of different overconsolidation ratios (OCRs).

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