RESPONSE OF OLIVE-VIEW-HOSPITAL TO NORTHRIDGE AND WHITTIER EARTHQUAKES

The purpose of this paper is to study the response of the conventional ly designed new Olive View Medical Center (OVMC) building at 16 km fro m the epicenter of the January 17, 1994 Northridge, California earthqu ake (M(s) = 6.8). OVMC is on an alluvial deposit. The building was sub jected to design level peak accelerations during the earthquake and su ffered only limited structural and nonstructural damage. The recorded motions at different levels of the OVMC building as well as its associ ated free-field sites are analyzed using spectral analyses and system identification techniques. The new OVMC building was conservatively de signed in 1976 with very high lateral load resisting capability-partic ularly as a reaction to the detrimental fate of the original Olive Vie w Hospital that was heavily damaged during the 1971 San Fernando earth quake. The original hospital building was later razed. The replacement structure, the new cross-shaped OVMC building, experienced peak accel eration of 2.31g at the roof while its peak ground floor acceleration was 0.82g. The free-field peak acceleration was 0.91g. The lateral loa d resisting system of the OVMC building consists of concrete shear wal ls in the lower two stories and steel shear walls at the perimeter of the upper four stories. Spectral analysis shows that this stiff struct ure was not affected by the long duration pulses of the motions record ed at this site.