Investigation into the quasi-plasticity damage model for concrete with micropores based on peridynamics

The non-linear performance of concrete is determined by the heterogeneous micro-structure of concrete. The existing methods mainly focus on numerical simulation of concrete at meso-scale. In view of this, the micro-calculation model based on bond-based peridynamics (BBPD) was established by the MATLAB-ABAQUS co-simulation method. In this study, based on the concrete plastic damage model in ABAQUS, combined with the quasi-brittle damage model and the basic characteristics of BBPD, a quasi-plasticity damage model was proposed which is suitable for the simulation of concrete. The calculation results show that the micro-model based on BBPD can well reflect the mechanical properties of concrete, and the crack propagation path is affected by the heterogeneity of concrete. At the same time, the quasi-plasticity damage model was established in which the mechanical behaviour of concrete in compression/tension can be considered simultaneously. For the distribution of pores, with the reduction of large capillary pores, the crack path inside the concrete is significantly simplified, and the distribution of cracks is significantly reduced. It can improve the mechanical behaviour of the material by optimising the pore structure and reducing the distribution of large pores.