Failure assessment of concrete shear walls under close-in blast based on viscous damage model

Abstract

In this research, failure of reinforced concrete shear walls under close-in blast is evaluated based on numerical analysis. By introducing the Duvaut–Lions type damage driving stress rate, a dynamic viscous damage evolution law for concrete materials is constructed under the framework of elastoplastic damage theory. The rate effect-induced increase in concrete strength is well captured by the suggested model. For validation, the response of reinforced concrete slabs in blast tests and their mechanical behaviors after explosion were calculated, and the results are in good agreement with the experimental findings. Under blast loads at various scaled distances, the failure of a series of reinforced concrete shear walls with different axial load ratios is simulated, and the post-blast residual bearing capacity is calculated using a three-step loading analysis process. The ratio of the residual axial strength is defined to assess the performance degradation of the shear walls after blast, and the effect of different factors on the failure of structures under blast is examined.