摘要：The study deals with the problem among to formally reduce a complex finite element structural model to a simpler one. As a sample task, the reduction of a girder model to the simpler equivalent membrane model has been investigated. The coincidence of model displacements at given loading conditions is employed as a criterion of mutual adequacy of the two models. Both static and dynamic displacements at selected reference points have been used in the expression of the penalty-type target function, the minimum of which indicates the best fit between the original and reduced models. The target function has been minimized by using the geometrical and physical parameters of a typical membrane element as optimization variables. The calculations have been performed in MATLAB environment. The validity of obtained parameters of the membrane model has been tested by investigating the original and reduced structures of different geometrical shapes at complex loadings.
