Stress analysis of multiple surface cracks with interactions

The existence of multiple surface cracks is a common problem in brittle materials under thermal shock loadings. Such structures have suffered sudden partial or total failure. The interaction of multiple surface cracks may affect the life-span of mechanical structures. In this paper, the thermal stress problem of an infinite plate of finite thickness containing multiple centrosymmetric semi-circular surface cracks normal to its face is investigated. The problem is resolved by using the superposition technique. The thermal stresses in the plate without the cracks are evaluated analytically. The perturbation problem for the cracked plate is modeled with the crack face tractions so as to negate the afore-mentioned thermo-elastic stresses through finite element method. Stress intensity factors of different crack configurations are obtained and illustrated.