Innovative concrete technology used in new bridge
Firth Industries’ innovative concrete technology used in construction of new Kopu Bridge
Work on the new $40 million Kopu Bridge is underway and Firth Industries Ltd has been contracted to supply concrete for the job.
The new 580 metre-long bridge over the Waihou River north east of Thames was fast tracked as part of the Government’s $500 million jobs and growth plan.
It will replace the existing one-lane bridge to improve traffic capacity for the thousands of holiday makers who travel along SH25 to and from the Coromandel Peninsula and reduce travel times between Auckland and Thames.
The main contractor for the Kopu Bridge project is HEB Construction and Firth will supply 6000 cubic metres of concrete for them from its Thames plant.
Construction has started on a platform from the western bank which will be built out to the swing span on the existing bridge. The platform will support the piling rig and allow construction of the piers for the new bridge to begin.
“We are delighted to be supplying HEB Construction for this long awaited bridge project, says Karl Campbell, Chief Operating Officer Firth Central.
“It’s the job of the century for Thames and will be welcomed by all those who use the Kopu Bridge,” he says.
While the bridge design itself is a reasonably straight forward design, it’s the environment that will provide the project with the most challenges.
Campbell says the Firth team will be operating under some difficult conditions such tidal flow and soft soil conditions, “The ground is very muddy and slushy and the water level constantly changes,” he says.
“Firth has created some special mixes for the project,” says Campbell.
“For the bridge substructure 50 mpa is being used with 8% micro silica to make the concrete more resistant to salt water marine attack,” he says.
The Kopu Bridge project will also provide for a new four-leg roundabout at the SH25/SH26 intersection and about 2.5 kilometres of associated approach roads including a new link road to the SH26 east of the bridge.
The project is
on track to be completed by mid-2012.