Title: Response of Slab-Column Connections under Dynamic Collapse Load Rates

Author(s): Aamer Jawdhari, Sarah Orton, Ahmed Sh. J. Al-Zuheriy, and Ying Tian

Publication: Structural Journal

Volume: 116

Issue: 5

Appears on pages(s): 55-66

Keywords: disproportionate collapse; dynamic load rate; flat-plate buildings; progressive collapse; punching shear

DOI: 10.14359/51715638

Date: 9/1/2019

Abstract:
During the initial stages of a collapse, the sudden failure of the initiating member (that is, column loss) can cause a dynamic load redistribution in the surrounding members. To determine a reinforced concrete (RC) building’s susceptibility to progressive collapse, the strength and ductility of its members under the dynamic loads need to be evaluated. Four isolated slab-column connections with different tension reinforcement ratios (0.64%, 1.0%) were experimentally tested by applying a dynamic load representative of the loading rate during the collapse of RC flatplate buildings. Companion to the experiments, detailed numerical analyses were conducted using the finite element packages LS DYNA and ANSYS. The dynamically tested connections had an increase in ductility compared to the statically tested connections; however, there was no significant change in punching shear strength. The increase in ductility may allow for more deflection before punching failure, thereby allowing more energy absorption and reduced dynamic action during collapse. Parametric studies were also presented on the effects of slab thickness and concrete compressive strength.