Rotational kinematic hardening model for sand behavior.

摘要

Large stress reversals occur in the ground in many practical engineering conditions. More specifically this behavior is found in geotechnical engineering in routine cases, like foundation design as well as during earthquakes and blasting. Predicting the stress-strain behavior of soil under such reversals is the aim of the present work.; Based on a series of experimental studies (e.g. Boonyachut (1977), Geiger (1979), Tanimoto et al. (1987) and Yasufuku et al. (1991)), a rotational kinematic hardening constitutive relation is proposed. This mathematical model is based on the theories of plasticity and elasticity and it is an extension of an existing isotropic hardening model (Lade and Kim, 1988 a, b and Kim and Lade, 1988).; Verification of this formulation is made using experimental results from a series of true triaxial tests (Lade and Yamamuro, 1995), as well as of torsion shear tests (Lade and Nam, 1983). Both series were performed on Santa Monica Beach Sand with 74% relative density. A computer code was written and used in the verification process. The stress-strain behavior of those tests was captured with good accuracy by the proposed theory.; Obstacles were found to the generalization of this approach. Previous studies on this subject matter (Inel, 1992) were found to be inaccurate and some suggestions that may lead to a more complete theory are presented.