Stress-Dilatancy Relationship of Zipingpu Gravel under Cyclic Loading in Triaxial Stress States

Abstract

AbstractIn this study, cyclic triaxial tests were performed on Zipingpu gravel, and they were followed by a discrete element study that was designed to investigate the stress-dilatancy relationship of gravelly soils under cyclic loading in triaxial stress states. Several conclusions emerged from the results. (1) A nearly linear relationship was found between the stress ratio η=q/p and the dilatancy ratio Dp=devp/desp under both conventional compression and extension monotonic loading. The slope parameter α, which relates η and Dp, was smaller during triaxial compression; (2) The stress-dilatancy relationship was different during the virgin and cyclic loading. The dilatancy line under cyclic loading was located inside the virgin/monotonic loading dilatancy lines, and the dilatancy relationship was related to the location of the most recent load reversal point; and (3) A nearly parallel linear relationship was found between η and Dp in the dη>0 and dη<0 paths under cyclic loading, with α smaller under cycli...