Coupled viscosity-damage model for concrete under high strain rate

A coupled viscosity-damage model of concrete under high strain rate is proposed based on the bi-scalar plastic-damage model. A rheological model is provided to explain the time delay mechanism of the damage under dynamic loading. A rate-dependent damage evolution is established by introducing the Duvaut-Lions type of the damage driving stress rate, and damage and viscosity are coupled. The operator splitting method is used to design an explicit calculation procedure. It is illustrated how the damage evolution predicted by the model differs for dynamic loading and quasi-static loading. Excellent comparisons between the simulated and experimental results show that the model can be used to reflect the strain rate effect of concrete under impact.