EXAMINING THE ADEQUACY OF SEPARATION GAPS BETWEEN ADJACENT BUILDINGS UNDER NEAR-FIELD AND FAR-FIELD EARTHQUAKES

Earthquake-induced pounding is a phenomenon that has been observed in almost every major earthquake since the 1960s. Pounding between adjacent buildings occurs due to insufficient separation and with different dynamic properties. This usually causes local damage, and in some extreme cases, total collapse of structures. Building codes in seismically active zones recommended a minimum separation gap between adjacent buildings to avoid pounding during severe earthquakes. AS1170.42007 is an Australian standard that requires 1% of the building height as a minimum separation gap between buildings to preclude pounding. This article presents experimental and numerical results to examine the adequacy of this specification to avoid seismic pounding between steel-frame structures under near-field and far-field earthquakes. It is found that AS1170.4-2007 is inadequate if the shorter building is used to estimate the required separation between adjacent structures under both near-field and far-field earthquakes. The code specification is adequate if the taller building is used to estimate the required separation between adjacent structures under far-field earthquakes only. The results are also compared with corresponding results obtained using the ABS and SRSS methods.