The damage to structures with multiple pin-holes and cracks is a typical form of damage that exists in airplanes of old age and many other engineering structures.

Based on the fundamental solution of elasticity for two-half elasticity plane,the boundary integral equation method is extended to study the fracture problem in bimaterial plane with multiple cracks subjected to arbitrary loads.

Based on the complex potential method about the plane theory of the elasticity of an anisotropic body,stress distributions in the plate with multiple cracks are obtained by using the conformal mapping and the Faber series expansion.

By using of complex variable and integral equation methods, the antiplane multiple elliptical holes and multiple cracks problem of infinite region was considered.

Numerical simulation for fracture propagation of multi-cracked rock materials using virtual multidimensional internal bonds;

According to character of procession of concrete material having size effect rule,effective crack propagation of concrete was investigated with size effect rule of fracture toughness of concrete,formula of effective crack propagation was obtained which reflected size effect rule,and then effective crack model of multi-crack concrete was obtained which was relative with dimension of the specimen.

Rock bridge fracture among multi-crack is one of the important reasons for rock mass failure.

Now, the safety of multi-cracks damage question is a extreme matter of concerning of the aeronautical engineering, Specially in crack point stress intensity factor solution aspect, Until now it is lack from the an.