Fracture energy based bi-dissipative damage model for concrete

An isotropic damage model for concrete is presented. The main features of t he model are: limited number of constitutive parameters required; independe nt modelling of tension and compression behaviour by means of two damage va riables and two separate activation criteria (bi-dissipative model); indepe ndent definition of tension and compression fracture energies by means of c onstitutive parameters which do not affect the pre-peak behaviour; consiste nt modelling of the unilateral effect upon transition from tension to compr ession. To overcome the problem of mesh dependence in the softening regime, the effectiveness of a fracture energy based regularisation strategy is sh own and the conditions for its correct application are defined. Comparisons of numerical simulations with experimental tests reveal the good accuracy and the robustness of the proposed model. (C) 2001 Elsevier Science Ltd. Af t rights reserved.