Mesoscopic analysis of Crack Propagation in Concrete by Nonlinear Finite Element Method with Crack Queuing Algorithm

By means of nonlinear finite element method, the initiation and propagation of cracks in concrete are analysed numerically at the mesoscopic level. The concrete is treated and modelled as a three-phase system consisting of coarse aggregate, hardened mortar matrix and interfacial transition zones between coarse aggregate and mortar matrix. Nonlinear constitutive properties of the materials before and after cracking are incorporated in the modelling. An integrated cracking criterion based on both tensile strength and fracture toughness is proposed to cater for stress concentration at crack tips, and a crack queuing algorithm is employed to simulate the stress redistribution and stress relief upon cracking. To illustrate the applications of the proposed method, an example of the cracking process of concrete is presented.