FRACTURE MECHANISM AND PREDICTION OF DEFORMATION OF MORTAR UNDER TIME-DEPENDENT LOADS BY MESO-SCALE ANALYSIS

Abstract

   Time-dependent constitutive law of Rigid-Body Spring Model (RBSM) was developed by separating mortar deformation into four components based on material information from micro to meso scale. In addition, the analysis could track residual strength up to the failure under creep and fatigue loading by installing a new method for determining failure state for load-controlled analysis. The analytical model could simulate mortar behavior under monotonic, creep and fatigue loading in terms of change in strength, stress-strain-time and S-N relationship. Furthermore, fracture mechanism of mortar under creep and fatigue loading was numerically explained. That is, failure happens when the material strength becomes less than the applied stress as a result of crack propagation with stress release-redistribution due to relaxation or unloading-reloading.