Seismic response of the Christchurch Women's Hopsital on 23 December 2011
The Christchurch Women's Hospital was instrumented in September 2011 with a network of highresolution accelerometers and displacement sensors in order to capture perishable data on the response of this base-isolated facility to a persistent sequence of strong earthquake aftershocks. On December 23, 2011 a swarm of aftershocks, about 20 km from the building site and 10 km deep, triggered over sixty structural response records. Five of these events had magnitudes greater than 5.0, generating ground motions and structural responses on the order of 0.1 g and measurable isolator deformations. The structural behavior of the isolation system and the statistics of the peak responses of the structural system are inferred from these records. Base shear (estimated from acceleration records) and deformations (computed from detrended acceleration records) enabled a measurement of the isolation system behavior. Models identified from the strongest responses can predict responses at lower intensities but not vise-versa.
