Cyclic Testing and Modeling of Interfaces

A new device for cyclic testing of large size interfaces between structural and geologic materials and rock joints is described. Test results are reported for a sand‐concrete interface, and are used to express shear stress as function of normal stress, relative displacement, number of loading cycles and initial density. Constitutive behavior of the interface is expressed as nonlinear elastic and simulates loading‐unloading‐reloading response by using a modified Ramberg‐Osgood model. The parameters for the models are found from a series of cyclic displacement controlled tests. Predictions of the constitutive model and a finite element analysis are compared with observed test behavior.