Investigation of pounding based on finite element analyses of two adjacent buildings, considering new equation of motion to measure impact

Abstract

Building pounding philosophy is the collision of adjacent buildings when earthquake take place and buildings show lateral movement. Providing suitable separation distance, impact force precludes and reduces the failure of construction elements. In this paper, building pounding between two reinforced concrete buildings with insufficient gap size is numerically investigated in order to study the impact force during seismic excitations. For this challenge, two to three story concrete buildings are modeled by finite element software. On the other hand, two mathematic models of RC buildings with lumped masses are considered to get the results of pounding and effect of impact on structural behavior. A mathematic program is used based on single degree-of-freedom (SDOF) equations to analyze the failure of models. Since calculation of impact forces depends significantly on link element assigned between two bodies, special link element is utilized. Used link element between two buildings is included in a spring with high stiffness and a viscous impact dashpot, which were located parallel in order to absorb the energy loss during impact. Finally, a new equation of motion is suggested to calculate the impact force. The accuracy of suggested equation is confirmed by energy equation. Key words: Building pounding, impact, dissipated energy, finite element.