The remarkable mechanical journey of Dennis across the skyline of Auckland’s Northwestern Motorway has come to an end.
The bright yellow lifting gantry has placed the last of 277 super heavyweight concrete beams into position on the Great North Road Interchange that straddles State Highway 16 at Waterview.
“Dennis finished as it began – a faultless and precise performance combining engineering muscle and innovation to construct the interchange,” says the Transport Agency’s acting Highway Manager Mieszko Iwaskow.
Almost immediately, with its job done, work began deconstructing the gantry which has been a feature of the NZ Transport Agency’s Waterview Connection project for the past two-and-a-half years.
The gantry has been sold by the Well-Connected Alliance, which is constructing the interchange and tunnels for the Transport Agency and the New Zealand Government.
The last super tee beam was lowered into position at the western tip of ramp 4 – the interchange ramp that will carry Waterview tunnel traffic on to the westbound lanes of the Northwestern Motorway. The interchange will connect the Northwestern Motorway with the Waterview tunnels and the Southwestern Motorway in early 2017.
The gantry was designed and built in Italy for the Waterview project. It was named Dennis to commemorate a project worker who had died from cancer.
For two-and-a-half years Dennis silently glided on rollers backwards and forwards across the interchange. It fetched and lifted enormous super t concrete beams weighing between 60 and 69 tonnes and up to 36 metres long, and then lowered them into place between the 55 columns or piers supporting the interchange. The beams are the foundations for the roads that will now be laid on top of them.
“Dennis has played an important role in the construction of the huge Waterview project that will be bring big changes to the way people travel around the city,” Mr Iwaskow says. “The team working with Dennis has worked really hard in some pretty extreme weather conditions to deliver a quality programme of work safely.”
The gantry did its work at night as lighter traffic volumes at that time meant any necessary safety closures of the motorway reduced the amount of disruption to drivers. During the day it rested above the live motorway below. Using the gantry instead of conventional cranes also protected important environmental spaces around the interchange.
When it opens next year, the Waterview Connection completes the Government’s $2.4b Western Ring Route – a 48km-long alternative motorway route around Auckland which reduces dependence on State Highway 1, especially through the CBD and the Auckland Harbour Bridge.