A project for Christchurch City Council, WSP’s involvement with the stadium consortium led by builder BESIX Watpac included the development of a seismic hazard assessment for the site.
Computers were used to model how strongly the stadium ground is likely to shake in future earthquakes, including from ruptures on the Alpine Fault and as part of the aftershock sequence from the 2010–2011 Christchurch earthquakes.
With nearby areas previously experiencing liquefaction, extensive geotechnical investigations were done throughout the site to understand ground make-up.
From there, WSP engineers developed a ground strengthening concept. Piers of tightly packed stone aggregate were installed under and around the stadium’s foundations, making the ground strong enough to support the stadium structure and help prevent liquefaction.
WSP project director Jon Fearnley says one of the questions asked on behalf of client Christchurch City Council during the design stage was whether a crowd-induced mini seismic event could damage the stadium, as happened during a Bruce Springsteen concert in Sweden in 1985.
“We were asked to undertake a review to see if that could be an issue here. It’s not, because of the different ground conditions.”
WSP also provided hydrogeology advice, looking at the impact on groundwater from construction, assessed the land for harmful substances, designed the site’s bulk earthworks, assessed the site for flood effects, and inspected works before the project contractor built the foundations.
Jon says it’s incredibly encouraging to see One New Zealand Stadium at Te Kaha open and already beginning to play such an important role for Christchurch.
“WSP is so pleased to have contributed to a project that will become a real community asset. It’s exciting to think about the wide range of events it will host in the years ahead for people to enjoy.”
WSP is proud to also have been involved with several other significant Christchurch rebuild projects, including the Avon River Precinct, Justice and Emergency Services Precinct, Te Pae Convention Centre, and Central Library.
