Simple Semi‐Loof Element for Analyzing Folded‐Plate Structures

Abstract

This paper presents a simple semi‐Loof plate bending element. Unlike Irons' semi‐Loof element (reported in 1976), it is not necessary to construct any Kirchhoff‐constraint equations for the proposed element. The complementary energy functional in which only the boundary deflection needs to be defined is employed. Flexibility and leverage matrices of the present element can be derived explicitly. Computational cost incurred by the numerical integration is thus eliminated. The element is deemed to be the most efficient hybrid semi‐Loof plate element, because of its minimal assumed moment space. It is also frame invariant, insensitive to nodal numbering, of the correct rank, and able to pass the constant‐moment patch test. Popular benchmark problems are examined and the accuracy of the proposed element is found to be comparable to that of Irons.