Cellular Automata to Simulate Split of Quasi-Brittle Materials

A cellular automata method is an efficient method that can simulate the process of self-organization of the complex system by constructing some simple local rules, which is fit to study material failure. In order to make full use of the advantages of cellular automata such as its intrinsic parallelism, localization and so on cellular automata model were presented to study the failure process of the quasi-brittle materials. The quasi-brittle materials can be divided into cell elements that are connected with beam elements. Displacements components are taken as the basic state. Based on the equilibrium equations and deformation equations local rules can be attained, which can update the states of the cells. Maximum tensile strain criterion and Mohr-Coulomb criterion are applied to judge the beginning of tensile failure and shearing failure. And based on damage mechanics deformation and strength properties of the damaged cell elements are estimated. Based on the cellular automata model the failure process of the quasi-brittle materials is studied. Split test is usually used to test the tensile strength of the quasi-brittle materials such as concrete and rock indirectly because of the difficulty of direct tension test. In order to understand the failure mechanisms of split test theoretical analysis, cellular automata simulation and experiments are used to analyze the split process. The research results show that split failure of the quasi-brittle materials is caused by tensile failure and cellular automata can simulate the split process of the quasi-brittle materials.