Non‐linear analysis of stiffened plates using super elements

Abstract

Abstract A new numerical technique for large deflection elasto‐plastic analysis of stiffened plates is presented. The method uses super finite elements which are macro elements having analytical as well as the usual finite element shape functions, specially designed so that only one plate element per bay and one beam element per span are needed. The large deflection theory by von Karman and the von Mises yield criterion and associated flow rule are employed. The governing equations are derived using the principle of virtual work, integrated numerically using Gauss quadrature and solved by Newton–Raphson iteration. Numerical solutions are presented for simple beams and plates, and plates stiffened in one or two mutually perpendicular directions. Good approximations are obtained with only one‐element representations of each plate bay or beam span with significant savings in computing time, costs and storage requirements as compared with using regular finite elements.