复合材料格栅结构的强度分析

复合材料格栅结构是由连续纤维缠绕的斜向及环向肋和蒙皮组成的结构。对ANSYS软件进行了二次开发,分别采用层合板和层合梁单元模拟复合材料格栅结构的蒙皮和肋。根据复合材料格栅结构的几何特征及其载荷分布特征,采用周期对称有限元模型,分别以最大应力准则、最大应变准则和蔡-吴准则和Chang刚度退化准则对轴压载荷作用下的复合材料格栅结构破坏过程进行了强度预测,计算结果表明采用蔡-吴准则预测并结合Chang刚度退化准则的计算结果与试验结果的一致性较好。

Strength analysis of composite grid stiffened structure

Composite grid stiffened structure is made up of continuous fiber wound oblique ribs, hoop ribs and skin. Through further development of FEM calculation software ANSYS, the skin and ribs are simulated by laminated plate elements and beam elements. According to the geometrical characteristics of composite grid stiffened structure and distribution of the load on it, cyclic symmetry finite element model is established. And based on the max-stress criterion, max-strain criterion, Tsai-Wu failure criterion and Chang stiffenss degradation criterion, the strength of the structure under the axial load is predicted and analyzed during failure processes. The calculation results based on Tsai-Wu failure criterion and Chang stiffness degradation criterion show a good agreement with the test results.