薄壳结构的向量式有限元屈曲行为分析

Vector form intrinsic finite element method for buckling analysis of thin-shell structures

基于向量式有限元三角形薄壳单元的基本理论,推导力控制法和位移控制法的基本原理及在向量式有限元中的处理方式,以实现薄壳结构的屈曲和后屈曲行为分析。在此基础上编制薄壳结构的屈曲计算分析程序,并通过算例验证。研究结果表明:所编制的向量式有限元薄壳单元程序可以用于薄壳结构的静、动力屈曲和后屈曲分析,验证了理论推导和所编制程序的有效性和正确性。无需进行特殊处理,采用位移控制法可有效越过屈曲极值点,跟踪获得薄壳结构大位移大转动、屈曲及后屈曲运动变形的全过程。

Based on the basic theory of triangular thin-shell element of VFIFE, the basic principles of force-controlled method and displacement-controlled method were derived, and the corresponding processes of VIFIFE were presented. Then buckling and post buckling behavior for thin-shell structures were analyzed. On this basis, a computer program of the buckling analysis for triangular thin-shell element was developed and numerical examples were provided. The results show that the static and dynamic buckling and post buckling analysis can be well performed for thin-shell structures by the developed program, verifying the validity and the correctness of the theoretical derivation and the computer program. Without special processing, the buckling extreme point can be acrossed effectively by adopting displacement-controlled method, and the whole deformation of large deformation and large rotation, buckling and post buckling of thin-shell structures can be tracked.