ANALYSIS OF POUNDING BETWEEN TWO BUILDINGS DURING AN EARTHQUAKE

Abstract

Structural pounding refers to the lateral collisions of adjacent buildings. Pounding occurs when building separations are insufficient to accommodate the relative motion of adjacent buildings. Review of past earthquake damage shows that pounding of adjacent buildings during earthquakes is a frequent phenomenon and an important cause of damage and in some cases it has led to collapse .

A formation and solution of the multi-degree-of-freedom equation of motion for pounding between two multistory buildings is presented. A numerical study of the parameters •affecting the pounding between adjacent reinforced concrete •• multistory buildings has been carried out. A dynamic analysis has been utilized to inve;tigate the pounding behavior of various combinations of adjacent reinforced concrete: building structures subjected to ground accelerograms. Five examples of pounding problem• have been considered in this study. Each example consists of a couple of two reinforced concrete buildings of different heights. These examples included seven different reinforced concrete building structures modeled as Ductile Mmn,ent-Resisting Frames, Dual System, Shear Wall System and Coupled Shear Wall system. The parameters studied have included variation of building heights, masses and stiffnesses and contact elastic spring stiffness. The effect of gap size on the pounding between adjacent reinforced concrete buildings during 'trong earthquakes has been also studied. The requirements for gap size of the Uniform Building Code (UBC-94), the Eurocode 8 (EC-8) and the Egyptian code for loads (ECL- 93) have been evaluated.

used

An artificial earthquake time history suitable for Egypt was generated and 't•o evaluate the requirements of ECL-93 for gap size. This artificial

earthquake has a peak ground acceleration of 0.3g and a duration of 20 seconds and was chosen to represent the "probable design level" earthquakes for zone 3 in Egypt. This artificial earthquake can be considered "Moderate Earthquake" as required by the ECL-93.