An Experimental Study on Dynamic Characteristics of Coarse-Grained Soil under Step Cyclic Loading

Abstract

The accumulated plastic deformation induced by a cyclic traffic load will lead to destruction of the subgrade. Coarse-grained soil is a widely used subgrade filler. The GDS dynamic triaxial test was carried out on typical coarse-grained soil fillers to investigate the influence of different confining pressures, consolidation ratios and numbers of cyclic actions on the hysteresis curve under step cyclic loading. The results show that surrounding pressure can significantly reduce the energy lost from a soil sample under cyclic loading. Under the same stress level, increasing the consolidation ratio can effectively reduce the area enclosed by the hysteresis curve. When the stress is increased above a certain value, the strain of the response clearly changes with an increase in the number of cyclic loading. The research findings can theoretically guide the design of coarse-grained soil roadbeds in practical engineering.