Performance of the base-isolated Christchurch women's hospital in the Sep. 4 2010 Dar field earthquake and the Feb.22 2011 Christchurch earthquake
The Christchurch Women's Hospital, completed in March 2005, is the only base-isolated building in the South Island of New Zealand. The displacement capacity of the base-isolation system and the super-structure ductility capacity are designed to meet 2000-year return-period demands. Detailed structural evaluations after the 2010 Darfield Earthquake and the 2011 Christchurch Earthquake revealed damage only to sacrificial non-structural components at the seismic gaps. Because the structure was not instrumented at the time of these earthquakes, basic design information, ground motion records from nearby sites, and first-hand accounts of the motion in the structure are used to estimate the responses to the main shock and a large after-shock. Results from this modeling effort are used to corroborate reports of structural response from staff present at the time of the main shock and aftershocks. Subsequent instrumentation of the structure is described and will be used to collect aftershock responses for validation of numerical models. © 2012 ASCE.
