Nonlinear analysis of reinforced concrete panels, slabs and shells for time-dependent effects

A numerical method of analysis was developed to trace the quasistatic responses of various types of reinforced concrete structures, of practical interest, under sustained load conditions. Time-dependent environmental phenomena, such as creep and shrinkage effects, were considered to obtain the evolution of the field variables of such structures in elastic and inelastic regimes. Ultimate collapses of shear panels, slabs of arbitrary geometry and free-form shell-type structures were then predicted considering local failures in steel and concrete along with the deterioration of structural stiffness due to progressive cracking. A finite element tangent stiffness formulation, coupled with a time step integration scheme was developed to analyze the reinforced concrete systems.