Determination and validation of Karagozian-Case Concrete constitutive model parameters for numerical modeling of dolomite rock

Abstract

The paper presents a methodology for the calibration of a Karagozian-Case Concrete (KCC) constitutive model for the simulation of dolomite rock. A series of basic experiments are performed under static and dynamic loading conditions, including uniaxial compression tests, triaxial compression tests at different confining pressures, and Brazilian tests for determining indirect tensile strength. A step-by-step procedure for determining the failure surface, the equation of state and damage parameters is proposed. The acquired data are validated using numerical simulations under loading conditions corresponding to those used in the experimental tests. A mesh sensitivity study is briefly discussed. Quantitative and qualitative comparisons of the numerical outcomes and experimental data reveal a good correlation. The KCC model reliably reproduces the rock behavior, including increased strength due to stress triaxiality and kinematic hardening with an increased strain rate. The damage evolution in the material is similar to that recorded by a fast camera during the experiments. The validated model will be used for modeling borehole blasting in further investigations.