Complex remediation of cultural icon wins prestigious ACE award
The complex engineering remediation work required to enable the iconic Christchurch Town Hall to be restored has won a prestigious Silver ACE Award.
The 2010 and 2011 Canterbury earthquakes caused significant liquefaction and lateral spreading to the land beneath the Christchurch Town Hall, which resulted in subsidence and damage to the superstructure.
Christchurch City Council embarked on a $167M+ conservation project that included novel ground improvement, a new raft foundation, re-levelling and strengthening of the superstructure, and refurbishment of the interior. The restoration project would ensure that the building became a focal point of the Performing Arts Precinct.
The Town Hall is listed by the New Zealand Historic Places Trust as a Category One building and has been acclaimed worldwide for its architecture and acoustics.
Tonkin + Taylor and Holmes Consulting were engaged to understand how much damage had occurred during the earthquakes to enable estimates for repair. Both engineering consultancies then worked together on the remediation.
Seismic strengthening concepts were developed to lift the seismic capacity and resilience of the complex. Essential to the improved resilience and strengthening was a scheme of cellular ground improvement created through subterranean jet grouting. Tonkin + Taylor geotechnical engineers Kirsti Murahidy and Mike Jacka developed and designed this revolutionary remediation and explain more in this video.
The ACE NZ judges commented that this was an impressive project with a significant budget that required both high levels of technical expertise and outstanding consulting practice from the consultants.
The Mayor of Christchurch Lianne Dalziel says both Tonkin + Taylor and Holmes Consulting were able to provide the council with exact information (in plain language) about the nature of the challenges that were faced during the restoration project.
Maintaining the original character and style of the building with its white marble, dark timber, rich red fabrics and vibrant artworks has resulted in a tangible link to pre-quake Christchurch.