The September 2010 Canterbury and February 2011 Christchurch earthquakes and associated
aftershocks have shown that the isolator displacement in Christchurch Women's Hospital
(Christchurch City's only base-isolated structure) was significantly less than expected. Occupant
accounts of the events have also indicated that the accelerations within the hospital
superstructure were larger than would usually be expected within a base-isolated structure and
that residual low-level shaking lasts for a longer period of time following the strong-motion of an
event than for non-isolated structures
