Determination of parameters for a model for the cyclic behaviour of interfaces

Abstract

AbstractThe cyclic shear stress‐deformation response of dry sand‐concrete interfaces is described using a modified form of a Ramberg–Osgood (R‐O) model. The model permits the description of the interface secant stiffness as a function of the normal stress, shear stress, sand density and number of loading cycles. Stiffening behaviour, or an increase in secant shear stiffness with number of cycles, may be represented, as well as degradation behaviour.Typical results from a series of cyclic direct shear tests are presented. A methodology is described by which the parameters for the (R‐O) model can be determined from the laboratory shear tests, and the functional forms of the parameters for the sand‐concrete interface are provided.The model is verified by predicting the response of two displacement controlled laboratory tests that were used for the determination of the model parameters. An additional verification is presented in which the response is predicted for a test not used in the parameter determination. The model is shown to simulate satisfactorily the cyclic response, including the effect of number of loading cycles.