Numerical Simulations on Cracking Process in Ceramic Specimens under Thermal Shock by Using a Non-local Fracture Model

In this paper, we present a finite element approach to fracture modeling for brittle or quasi-brittle materials and its application to thermal shock crack simulations. The proposed fracture model is constructed on the basis of the conventional maximal principal stress criterion for uniform tensile loads and the Griffith-Irwin criterion for crack propagation prediction. Consequently, the proposed fracture criterion can be used to predict both the crack initiation and the crack growth. By using the proposed model, we carried out detailed numerical simulations on cracking process of ceramic materials subjected to thermal shock loading. The random aspect of strength and toughness of the material was considered by generating stochastically their spatial distribution. The comparison with the experimental results shows that the periodic and hierarchical structure of the crack pattern is faithfully reproduced by the numerical simulations.