Nonlinear Analysis of RC Shells of General Form

A general finite element method of analysis is developed to analyze reinforced concrete shells of general form and slabs of arbitrary geometry under dead load and monotonically increasing live loads. The method can be used to trace the load-deformation response and crack propagation through the elastic, inelastic, and ultimate ranges. The nonlinear analysis includes cracking with a tension stiffening effect and the elastoplastic behavior of the concrete and steel reinforcement. The coupling between the membrane action and the bending action due to material asymmetry is also included. Validity of the method is studied by comparing analytical results with experimental data. It is found that the tension stiffening effect has a significant influence on the post-cracking response of underreinforced concrete structures. The importance of the failure criteria and flow rules is also studied.