Numerical simulation of the failure process of reinforced concretestructures based on the rigid body spring method

Abstract

Considering that continuous numerical methods cannot accurately describe the physical characteristics of cracks and discontinuous numerical methods cannot reflect structural stiffness,a rigid body spring model is proposed in this paper to analyze the failure process of reinforcement concrete(RC) structures.In the proposed method,concrete is simulated by the rigid body spring model based on Voronoi diagram random generated mesh.Reinforcement is modeled as a series of bar elements and the bond-slip characteristics between reinforcing steel and concrete are also considered by introducing special linkage elements.The spring stiffness of concrete is determined from the uniaixal stress-strain curve of concrete,and the shear failure behavior of concrete is judged by the Mohr-Coulomb criterion.A home-made program based on FORTRAN Language is developed and used to analyze the failure processes of a Z-type component under direct shear loading and a RC beam under two-point loading.The comparison of numerical results and experimental results show that the proposed method can simulate cracking behavior of RC structures precisely,and can provide the physical characteristics of cracks.The ultimate strengths and load-deflection response of the test beam predicted by the proposed method are in good agreement with the experimental results,which means the proposed method is feasible and effective.

Keywords

• reinforced concrete structures
• failure process
• the rigid body spring method
• propagation of concrete cracks
• material nonlinearity