A two-scale stochastic damage model for concrete under fatigue loading

Abstract

The microscopic stochastic fracture model is extended by introducing a concept of microscale damage, whose evolution law is derived by an energy analysis on the propagation of the cracks from nano- to microscale. A material parameter termed nano-to-micro comprehensive fracture energy is found to play a key role in the random and nonlinear behavior of concrete. It is shown that the proposed model can simulate the mean and standard deviation of the complete stress–strain curve of concrete very well. Moreover, the fatigue life, stiffness degradation and their inherent randomness under various loading conditions can be well predicted by the model.