Nonlinear model for nonprestressed and prestressed slab-column connections under lateral load effects

Abstract A nonlinear modeling approach was developed to capture the response of slab-column (SC) frame members under combined gravity and lateral load demands. The occurrence of punching shear or flexure-punching shear failures at slab-column connections is detected by monitoring the column drift and providing a limiting drift value based on the gravity shear demand at the connection. Following detection of failure, plastic springs at the member ends are adjusted to provide a reduced stiffness and moment carrying capacity. Nonlinear modeling parameters developed for use in ACI 369.1 and ASCE 41 for SC connections without shear reinforcement were then reviewed by applying the developed nonlinear model to several SC connection tests reported in the literature. The model was implemented in the OpenSees computational platform. The backbone responses predicted by the proposed SC connection model are consistent with the experimental measurements. In addition, the proposed nonlinear modeling parameters are shown to provide a good estimate of the nonlinear response of SC connections under gravity and lateral loads that induce punching shear or flexure-punching shear failures.