薄壳结构碰撞、断裂和穿透行为的向量式有限元分析

Collision-contact,crack-fracture and penetration behavior analysis of thin-shell structures based on vector form intrinsic finite element

在向量式有限元三角形薄壳单元的基本理论中,引入薄壳结构碰撞、断裂和穿透等复杂不连续行为的模拟机制。采用"点-三角形"检测和罚接触力法模拟碰撞检测和碰撞响应,获得薄壳结构碰撞接触的全过程;采用塑性失效应变准则和质点分裂方式,获得薄壳结构断裂和破碎的全过程;进而结合碰撞检测、碰撞响应、失效应变准则以及质点分裂处理方式,获得刚体穿透薄壳结构的全过程。基于此,编制了向量式有限元考虑薄壳结构的碰撞、断裂和穿透行为的分析程序,并通过算例分析验证了理论推导和所编制程序的有效性和可靠性,体现了向量式有限元方法在薄壳结构复杂不连续行为分析领域的优势。

In the theoretical framework of the triangular shell element based on the vector form intrinsic finite element （VFIFE） , the processing mechanisms of complex discontinuous behaviors such as collision-contact, crack-fracture and penetration for thin-shell structures were introduced. The ＇point-triangle＇ detection and the penalty contact force method were adopted separately for the problems of collision detection and collision response, and the whole process of structural collision-contact was tracked. The plastic failure strain judgment criterion and the particle splitting method were adopted to track the whole process of structural crack-fracture. Then, the combination of the collision detection, the collision response, the failure strain judgment criterion and the particle splitting method were adopted, and the process of penetration for rigid body-thin-shell structure was achieved. Computer programs with collision-contact, crack-fracture, and penetration behavior analysis for the thin-shell structure were then developed, and the validity and the reliability of the derived theory and the developed programs were verified through numerical examples. It is shown that the VFIFE is advantageous in the analysis of complex discontinuous behaviors for thin-shell structures.