A coupled 2D RBSM-Voronoi model for simulating fracture behaviors of plain concrete components

With the aim to alleviate the influence of mesh grid on numerical results, a coupled 2D RBSM-Voronoi model is proposed in this paper to simulate the fracture process of plain concrete components. In the proposed model, voronoi diagram is introduced to generate random grid, and concrete is partitioned into a series of voronoi cells, which are regarded as rigid blocks. The adjacent cells can separate and intrude at the interface, which make the proposed model a convenient tool to simulate the propagation of cracks. A pair of uniform springs are defined at the interface of adjacent cells, and the constitutive model based on traction-separation criterion is proposed and modified to define the weaken behavior of interface spring. To identify the application and accuracy of the proposed model, numerical studies about concrete components are conducted and compared with experimental results. According to the comparison results, it can be concluded that the coupled RBSM-voronoi model is an efficient and accurate method to analyze the fracture process of concrete components, especially for the components under compression shear loading, and the random voronoi grid can greatly alleviate the sensitivity of mesh grid on numerical results.