Shear coupling effect of monotonic and cyclic behavior of the interface between steel and gravel

Abstract

Three-dimensional behavior of the interface between a structure and gravelly soil is of great concern in the design and construction of large-scale projects. A series of three-dimensional tests were conducted to investigate the effect of shear coupling on the monotonic and cyclic behavior of such an interface. In these tests, monotonic shear was applied to the interface first and then the monotonic and cyclic shears were applied in the orthogonal direction while the original shear was maintained. Based on the test observations, the shear strength of the interface was found to be independent of the shear coupling and proportional to the normal stress. Significant tangential displacement is induced by the orthogonal shear application and the deflection direction of the tangential displacement is proportional to the square of the ratio between the orthogonal shear stress and shear strength. The interface exhibits significant dilatancy due to a three-dimensional shear application, which is divided into reversible and irreversible components. Shear coupling remarkably affects the magnitude and transition shear stress of the reversible dilatancy component. There persists a significant aeolotropy of the interface evenly under the shear coupling condition. Particle crushing near the structure was observed to be enhanced due to the shear coupling.