Performance Evaluation of Elastoviscoplastic Concrete Model

In this study we examine the dynamic strength enhancement and the regularization properties of viscoplasticity with regard to strain softening in tension. To this end we extend the elastoplastic concrete model by Kang and Willam to the viscoplastic DuvautLions overstress formulation. Our main focus is (1) the difference of dynamic strength increase in tension, compression, and shear when only a single viscosity parameter is introduced in the form of the relaxation time, and (2) the regularization of localized failure when we compare elastoviscoplastic with elastoplastic strain softening. Thereby, it is understood that the brittle/ductile modes of failure in tension, compression, and shear depend not only on the loading path, but also on the loading rate at high-speed impact.