This paper investigates the applicability of the DK and DKM shell element classes for the first time within the framework of the standard (and sequential) finite-element-based limit analysis, which is a direct method used for determining the plastic collapse (and post-collapse) behaviour of structures. Despite these elements not being able to guarantee a strict upper bound, it is shown that they exhibit a significantly lower discretization error compared to the strict upper-bound formulated shell elements used in literature. Among these elements, the superiority of quadrangle elements over triangle elements is observed. The numerical results are also compared with the MITC shell elements, which have been shown to converge only in the pure membrane case.

翻译：本文首次在标准（及顺序）基于有限元的极限分析框架内研究了DK壳单元与DKM壳单元的适用性。极限分析是一种用于确定结构塑性坍落（及后坍塌）行为的直接方法。尽管这些单元无法保证严格的上限解，但研究表明，与文献中采用严格上限公式的壳单元相比，它们展现出显著更低的离散误差。在这些单元中，四边形单元相较于三角形单元表现出更优的性能。数值结果还与MITC壳单元进行了对比，后者已被证明仅能在纯膜情况下收敛。