Nonlinear analysis of RC shell structures using laminated element. I

Abstract

An incremental variational formulation is presented for large deflection analysis of elastic-plastic continuum by considering the energy consistency of a nonlinear multivariable discrete system based upon incompatible trial functions. The functional is given in orthogonal curvilinear coordinate system and the initial stress procedure has been introduced. Equilibrium imbalance correction is included to prevent drifting of the solution during the incremental process. As an initial application of the suggested formulation, a hybrid stress laminated shell element in which an energy constraint is introduced to improve the element performance ,has been developed to analyze the through-thickness plastic behavior and the progressive cracking in reinforced concrete plates and shells. It is of quadrilateral shape with only four corner nodes and can be used for both shallow and deep laminated shells with satisfactory numerical characteristics. Example problems are also included to illustrate the element performance.