The factory that will produce more than 24,000 concrete segments to line the motorway tunnels for the NZ Transport Agency’s Waterview Connection project has been officially opened by Auckland’s mayor, Len Brown.
The 6000 square metre factory in East Tamaki has created 70 new jobs, and it is the most modern pre-cast concrete manufacturing facility in Australasia.
The Transport Agency’s Highway Manager, Tommy Parker, says that during the next two years, the factory will manufacture the linings for Waterview’s twin 2.4km-long twin tunnels with to-the-millimetre precision, and the strength and durability to withstand 100 years of demanding use.
“It is an entirely new facility, built by a partnership between the tunnel project’s Well-Connected Alliance and Auckland company Wilson Tunnelling and equipped with some of the most up to date concrete batching and moulding equipment in the world,” Mr Parker says.
“It is creating 70 new jobs, almost all of which have been filled by people from the factory’s neighbourhood in Auckland south. And it will be a major consumer of locally produced aggregate and cement over the next two years.
“Next to the tunnels themselves, the pre-cast factory is probably the Waterview Connection project’s most exciting story,” Mr Parker says.
Other guests at today’s opening included Jami-Lee Ross, the Government MP for Botany, and executives from the Transport Agency and the Well-Connected Alliance, which is constructing the Waterview project.
Waterview’s twin tunnels are the key feature of the new six-lane, 5km motorway being built for the Transport Agency by the Well-Connected Alliance in west Auckland. It will join the Southwestern and Northwestern motorways (State Highways 20 and 16) to complete the city’s 48km-long Western Ring Route – one of the Government’s National Roads of Significance.
The lining for the Waterview tunnels will comprise 2,414, 14m-diameter rings of concrete, each two metres wide and each comprising 10 segments. Nine of the segments will weigh 10.5 tonnes while the tenth will be a smaller ‘key’ segment that locks the ring together.
Mr Parker says production of the individual segments for each ring began in August. It is planned to have 180 rings completed by the time ‘Alice’ - the project’s tunnel boring machine - is launched later this year. Inside the tunnels, they will be installed by ‘Alice’ as the machine bores her way underground.
“After every two metres that is excavated, the tunnel boring machine will stop while each ring of lining segments is installed and grouted into place. The machine then uses that ring to push off, to excavate the next two metres of tunnel.”
He says the tunnel boring machine will install six lining rings every 24-hours ‘Alice’ is working (a total lining of 12 metres). The pre-cast factory will manufacture 40 rings (400 segments) per week using four sets of moulds specially designed and fabricated in France for the Waterview tunnels.
In addition to tunnel lining segments, the pre-cast factory will produce 2,400 culvert units to go beneath the motorway through the tunnels and 279 1500mm deep bridge beams for new ramps at the Great North Road motorway interchange on State Highway 16.
Wilson Tunnelling which specialises in precision precast segmental linings, is part of the Wilson Group of companies established 27 years ago. The group employs 200 people and works throughout Australasia producing pre-cast concrete for commercial, residential, civil and major infrastructure projects.