Plastic-Damage Model for Interfaces in Cementitious Materials

Abstract

A new constitutive model for interfaces in cementitious materials is presented. The model uses a plastic-damage formulation in which the undamaged material component is assumed to remain elastic and plasticity is applied to the damaged component. A contact parameter is incorporated, which simulates particle separation. The constitutive model is implemented in a single-point stress–relative displacement program as well as a nonlinear beam analysis program for the simulation of notched beam fracture tests. The performance of the model is assessed against a variety of experimental data, including shear and indirect tension tests with both monotonic and cyclic loading regimes. The simulations demonstrate the potential of the new model to predict the response of joints in both shear and direct tension and to capture the major features of joint behavior including postpeak softening, stiffness degradation, postcrack friction, joint dilation, and complete crack closure under compressive loading.