中文摘要：

由于具有预先满足层间应力连续的优点,锯齿理论被广泛研究和应用.然而,至今锯齿理论仍然存在如下难题：基于锯齿理论构造单元时,需使用满足单元间C1连续的插值函数,难于构造多节点高阶单元,而且精度较低.如果这些问题不被重视和解决,应用此类理论分析复合材料力学问题可能得出不恰当的结论.通过发展高精度的考虑横法向应变的C0型锯齿理论,论文将克服已有锯齿理论遇到的上述难题.基于发展的锯齿理论,构造三节点梁单元验证发展理论模型的性能.

英文摘要：

Zig-zag theory has a merit of continuity conditions of transverse shear stresses being a priori satisfied,so it is widely studied and used. However, in the zig-zag theory, some problems have not yet solved. The C1 shape functions have to be required during its finite element implementation, so that it is dif- ficult to construct higher-order element based on the zig-zag theory. Moreover,previous zig-zag theories are less accurate in comparison with three-dimensional elasticity solutions. If these problems are neglected, some improper conclusions might be drawn when these zig-zag theories are used to analyze the mechanical problems of laminated composites. By proposing an accurate C~-type zig-zag theory considering transverse normal strain,difficulties encountered by previous zig-zag theories are overcome in this paper. Based on the proposed zig-zag theory, a three-node beam element is constructed to verify the performance of the pro- posed model.