Analysis of Cyclic Shear Characteristics of Coarse-Grained Soil Reinforced with Geogrids

Abstract

To investigate the cyclic shear behavior of geogrid-reinforced coarse-grained soil and the interaction mechanism between the geogrid and the soil interface, a series of cyclic shear tests with a large number of cycles were conducted under various shear displacement amplitudes, as well as different normal stresses. The results indicate that under various shear displacement amplitudes, the geogrid-reinforced coarse-grained soil interface exhibits a slight softening characteristic, and a characteristic of shear dilation followed by shear contraction in terms of volumetric deformation. The peak strength of the interface gradually decreases as the shear displacement amplitude increases. The shear stiffness is negatively correlated with the shear displacement amplitude, and the damping ratio increases with increasing shear displacement amplitude. The geogrid-reinforced coarse-grained soil exhibits a softening behavior during the cyclic shear under different normal stresses. Furthermore, as the normal stress increases, the shear softening behavior becomes more significant. The geogrid-reinforced coarse-grained soil interface exhibits the characteristic of slight shear dilation followed by shear contraction during cyclic shearing, and the final shear dilation increases with an increase in the normal stress. In addition, the shear stiffness is positively correlated with the normal stress, and the damping ratio decreases with an increase in normal stress.