An improved peridynamic model for quasi-static and dynamic fracture and failure of reinforced concrete

In this paper, an improved peridynamic model is established to characterize the bond-slip behavior between ribbed steel rebar and concrete. An interfacial force term is introduced into the description of interaction between rebar and concrete considering the chemical bonding force, the friction, as well as the mechanical bite force, and a size-dependent non-uniform discretization algorithm for rebar and concrete is developped to reduce the calculation cost in numerical simulations. An equivalent modeling approach for ribs is presented as well, which can accurately reflect the interaction between ribs and concrete. Validation of the proposed model and approach is established through modeling pull-out problem of ribbed steel rebar, in which the crack initiation and propagation during the pull-out process can be accurately captured. Moreover, the dynamic fracture and impact failure of reinforced concrete are numerically modeled and analyzed. The numerical predictions are consistent with available experimental results, in terms of fracture characteristics of concrete, deformation of rebars, as well as the force-displacement curves.