Unified Modeling of Monotonic and Cyclic Behavior of Interface Between Structure and Gravelly Soil

This paper describes an elasto-plasticity damage model, termed the EPDI model, of the interface between a structure and gravelly soil. The formulations are derived on the basis of a new model framework, with test-basis concepts and assumptions, for a unified description of monotonic and cyclic behavior of such an interface. The model parameters, with physical meaning, are easily determined from a group of cyclic shear tests and a confining compression test. The comparisons of model predictions with the results for a series of tests under varying loading conditions demonstrate that the EPDI model is effective in accurate description of monotonic and cyclic stress-strain relationship of the interface between a structure and gravelly soil with capturing new features, including: 1) shear stress-strain relationship and comprehensive volumetric strain response (e.g., partly dependent on shear strain); 2) volumetric strain response that is dependent on the shear direction; and 3) evolution of behavior of the interface associated with the evolution of physical state.