改进的复合材料斜接结构胶层应力半解析法

引入微分概念和复合材料铺层刚度分配原则,形成一种改进的求解复合材料斜面对接结构胶层应力的半解析方法 MAM(Modified semi-Analytical Method)。首先,针对铺层角度及铺层数不一致的情况,采用有限元法(FEM)平面应变模型对MAM进行验证;然后,分别用平均剪应力法、FEM及MAM预测了复合材料斜接结构的承载能力并与试验值进行对比;最后,利用MAM分析工程应用问题,考虑了被粘结体刚度不匹配及胶层厚度的变化。研究结果表明:MAM适于设计复合材料斜接结构;采用MAM能得到胶层应力的尖峰值,且应力分布与FEM计算一致。

Modified semi-analytical method for adhesive stress of scarf joints in composite structure

Modified semi-analytical method (MAM) was created by applying the concept of differential and rule of composite ply stiffness distribution, which can be used to predict adhesive stress for scarf joints in composite structure. Firstly, validation of MAM was studied through the models of different ply angles and number of plies with finite element method (FEM) 2D plane strain. Then, the load carrying capacity of the composite scarf joints was predicted with average shear stress method, FEM and MAM. At last, MAM was used for analyzing engineering applications which concerned scarf joints with dissimilar modulus of adherends and variation of adhesive thickness. The comparison of results of these methods with the test values demonstrates that MAM is appropriate for designing scarf joints in composite structures, and the peak value of adhesive stress can be obtained with MAM and stress distribution is in accord with FEM calculation.