Cyclic Testing and Modeling of Interfaces

TLDR

The study introduces a device for cyclic testing of large‑scale interfaces between structural and geological materials and rock joints. The device measures cyclic loading of interfaces, and the interface behavior is modeled as nonlinear elastic using a modified Ramberg‑Osgood model calibrated from cyclic displacement‑controlled tests. Test results on a sand‑concrete interface show shear stress depends on normal stress, displacement, cycle number, and density, and the model and finite element predictions agree with observed behavior.

Abstract

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.