A 3D stochastic damage model for concrete under monotonic and cyclic loadings

A stochastic damage model previously proposed by the author and Li for concrete under monotonic and cyclic loadings is extended to 3D stress states. Specifically, a novel expression form of damage energy release rate, which is the damage driving force thermodynamically, is initiated, and some basic concepts related to concrete damage evolution are further demonstrated. Careful validation of the model against existing experiments reveals that the model is able to well capture the rate effect of concrete and to realistically simulate the monotonic strength, cyclic life, and their accompanying randomness for a wide range of stress states from uniaxial tension to confined compression.