Evaluating undrained cyclic strength of gravelly soil by shear modulus

The possibility of evaluating undrained cyclic strength of natural gravelly deposits using shear moduli was investigated. Through this study, the following conclusions are drawn. 1) It was found that cyclic shear moduli at relatively large strain amplitude were closely related with undrained cyclic strengths, irrespective of the effective confining pressure, grain size distributions and whether or not the samples are intact, whereas there seems no unique relationship between initial shear moduli and undrained cyclic strengths. 2) It was found that the G/G(0)similar togamma relation of a intact sample can be approximated by that of the reconsitited sample depending on the initial shear modulus of the intact sample. Based on this fact and the relationship mentioned in 1), a simplified procedure to evaluate undrained cyclic strength of gravelly soil by initial shear modulus of the ground and shear modulus of the disturbed sample was proposed.