Orthotropic Bimaterial Plane Interface Edge Stress Analysis Of The Complex Variable Method

In modern, composite materials for its superior performance have been widely used in production, all areas of life. Composite material is defined as two or more different materials in different ways to combine one materials.The combining materials are always destroyed form union or near the interface firstly, so to analysis of interface end as a reliant evaluation to strength of composite materials have important significance. In the research of composite interface mechanics, there have been made some important achievements in the stress analysis about isotropic bimaterial interface end^[1-7]. In Ref^[8-12], the theoretical solutions to the stress field, displacement field of dissimilar orthotropic composite materials are deduced, indicating that there is no oscillatory singularity. In Ref^[13], the problem of orthotropic bi-materials anti-plane interface end of flat lap was studied. The result shows: this type of problems has one singularity. But the plane flat lap interface end that is commonly used in the repair of Shell structure. By analyzing the the stress field of flat lap interface end, it will help to choose the right combination of materials. In the present paper, the orthotropic bi-material plane flat lap interface end is studied by using the composite complex function method of material fracture and constructing new stress functions. The analytical expressions of the stress field, the displacement field, and the stress intensity factor of the flat lap interface end near the crack tip are derived, in the cases that (1) :Δ1 > 0andΔ2 > 0;(2):Δ1 < 0andΔ2 < 0;(3):Δ1 > 0andΔ2 < 0. It is indicated that there is no oscillatory singularity. The correction of the derived equation is verified by matlab programming.