Following the Christchurch earthquakes, a 200m section of Fitzgerald Ave’s northbound lane came precariously close to sliding into the adjacent picturesque Avon river as a result of major subsidence.
The Stronger Christchurch Infrastructure Rebuild Team (SCIRT) appointed the Downer delivery team to undertake repairs to the road. Road repairs included rebuilding a retaining wall, carriageway, cycleway and footpaths. The road would be completed with CSP Pacific’s road safety products.
|(SCIRT) is a partnership between Christchurch City Council (CCC), Canterbury Earthquake Recovery Authority (CERA), New Zealand Transport Agency (NZTA), and contractors City Care, Downer, Fletcher Construction, MacConnell Dowell and Fulton Hogan.|
Initially an innovative technique was used to stabilise the ground and adjacent riverside retaining wall that supports the road with 800 stone columns, each 600mm in diameter, inserted into the ground to a depth of ten metres over the 200m length of road.
Anthony Burgess, Contract Manager for Downer explains, “we used a piling rig to insert the stone columns. We also have used five layers of tensile grid that runs perpendicular to the wall to add additional strengthening and ground stabilisation.”
The purpose of the work is to make the surrounding ground denser and stronger, and with improved ground water drainage it should prevent liquefaction and help prevent structures from being affected by any future earthquake events.
Once the ground stabilisation was complete Downer installed the 1.5m wide precast concrete wall panels which varied in height from 1.1 - 3.2m. “We are currently working on the elevated walkway below the wall and while we do this CSP Pacific are supplying the Bridge Rail Guardrail System with handrail to the road above. Even though this has taken nearly a year to complete everything has gone pretty well.”
“All the contractors working around the city are happy to be involved in getting Christchurch back on its feet, which includes CSP Pacific,” says Ian Rowland, Sales Engineer Upper South Island for CSP Pacific. “We are all working to the same goal.”