ISSN: 1945-7545
CODEN: GTJODJ
Page Count: 7

G_max-qc Relationships for Clays

Mayne, PW
Associate professor and assistant professor, Georgia Institute of Technology, School of Civil Engineering, Atlanta, GA

Rix, GJ
Associate professor and assistant professor, Georgia Institute of Technology, School of Civil Engineering, Atlanta, GA

Abstract

Data are compiled from 31 clay sites where in-situ measurements of initial tangent shear modulus (G_max) and cone tip resistance (qc) were available. Values of G_max were obtained from either seismic cone penetration (SCPT), crosshole (CHT), downhole (DHT), or spectral analysis of surface wave (SASW) tests, and readings of qc were taken either by regular cone penetration (CPT) or piezocone (CPTU) tests. Multiple regression analyses indicate that in-situ values of G_max depend on void ratio (eo), overburden stress (σ′_vo), and stress history (OCR), as previously established from laboratory resonant column tests. Since qc also depends on σ′_vo and OCR, a moderate association between G_max and qc is possible, despite their incompatible strain levels. For preliminary correlative purposes, a power function relates in-situ G_max, qc, and eo in clay deposits having a wide range in plasticity, sensitivity, stress history, and consistency.

Keywords:
cone penetrometer, clays, cohesive soils, correlation technique, elasticity modulus, field data, field investigations, geophysics, penetration resistance, penetration tests, piezocones, seismic waves, shear wave, wave velocity, in situ testing, seismic investigations

Paper ID: GTJ10267J
DOI: 10.1520/GTJ10267J
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