In order to predict the mechanical responses of Haikou red clay under over-consolidation and cyclic loading conditions, this paper adopts a unified critical state model considering the over-consolidation and cyclic behaviour (i.e. CASM-kII) for the constitutive modelling. Although the CASM-kII can reasonably characterize the isotropic and hardening behaviours of soils, the dilatancy law of original CASM-kII is modified in this paper to achieve a better agreement with stress-dilatancy relation observed in laboratory test. Through the comparisons of a series of experiment data and simulated results, it is found that the modified CASM-kII can accurately characterize the over-consolidate and cyclic responses of Haikou red clay under different loading conditions.

来源平台：NATURAL GEO-DISASTERS AND RESILIENCY, CREST 2023