Mesolevel simulation of reinforced concrete structures under impact loadings

Reinforced concrete structures are often subjected to extreme dynamic loading conditions due to direct impact. This paper deals with the numerical simulation of the effect of impact loadings on reinforced concrete structural members such as columns, beams and slabs. Concrete is modeled by a three-dimensional mesolevel lattice model, which can predict accurately concrete behavior in a wide range of loading conditions. The adopted constitutive law simulates fracture, friction and cohesion at the meso-level and takes into account the strain rate dependence of concrete behavior. A mesh of plastic beam elements simulates the effect of steel reinforcement. Since the nodes of the reinforcement do not coincide, in general, with the nodes of the lattice system ad hoc coupling algorithms are proposed. The mesolevel model for concrete and the concrete-rebar coupling algorithm are implemented in the framework of the object oriented dynamic finite element code MARS. Finally, numerical simulations of the behavior of reinforced concrete structural members subjected to impact loading are performed and the numerical results are compared with experimental data gathered from the literature.