Race against time

When part of New Zealand’s State Highway 25A was washed away in a storm, the clock immediately started ticking on a project to reconnect the communities it served as quickly as possible. Contract awarded by the McConnel Dowell and Fulton Hogan joint venture with designers Beca and Tonkin + Taylor, mageba was happy to help the joint venture by ensuring the required bearings and expansion joints were designed, manufactured and delivered to site in good time.

State Highway 25A on New Zealand’s North Island suffered severe damage during a major storm at the end of January 2023, with a section of length 120 m being completely washed away. Due to the road’s critical function in serving the communities on the Coromandel Peninsula – any detour involving a much longer journey – the highway reinstatement work had to be undertaken as a matter of great urgency.

Following consideration of the options, NZ Transport Agency Waka Kotahi in consultation with the industry decided that the best and quickest way to reopen the road was to construct a new bridge to span the gap. Site investigation work, including taking and evaluation of core samples, assisted in coming to the conclusion that a three-span, 124 m-long bridge was the best solution. The quick implementation was helped by the transport agency’s decision to use a bridge design that it already had, and its ability to repurpose steel plates that had already been purchased for another project. Then the fabrication and construction was carried out in record time, with work ongoing around the clock – both on site and in the factory where the steel girders were manufactured.

With quick design and construction of the main steel-and-concrete structure organised, the rapid reopening of the road connection still depended on the accelerated supply of the bearings needed to support the superstructure and of the expansion joints required to bridge the movement gaps at each end. This is where mageba stepped in – designing and fabricating these key structural elements and delivering them to site quickly enough to avoid slowing down the construction programme. While the RESTON®SPHERICAL bearings were fabricated at mageba’s factory in Australia, the TENSA®GRIP expansion joints were manufactured at the company’s facility in Shanghai, requiring the use of air freight to minimise the transport time.

The road is now scheduled to reopen on 20th December 2023 – three months ahead of schedule and in time for Christmas and the “down under” summer holidays. Our teams in Australia and Shanghai are glad to have helped make this happen – when speed really matters, mageba is at your side.

Bridge designer: BECA
Contractor: McConnell Dowell and Fulton Hogan JV
Owner: Waka Kotahi NZ Transport Agency

State Highway 25A on New Zealand’s North Island showed signs of distress following a cyclone in January 2023 (©nzta.govt.nz)

Following a second cyclone the next month, a major landslide resulted in a 120 m-long gap opening up in the highway (©nzta.govt.nz)

Following site investigation and consideration of all options, NZ Transport Agency Waka Kotahi decided to construct a new bridge, 124 m long and with piled foundations, where none had existed before (©nzta.govt.nz)

Construction of the new Taparahi Bridge progressed extremely quickly thanks to the use of an existing bridge design, repurposing steel plates from another project to fabricate the girders steel, and around-the-clock work shifts

One of the new RESTON®SPHERICAL bearings installed to support the Taparahi Bridge’s superstructure following accelerated design, fabrication and delivery by mageba Australia

Installation of a TENSA®GRIP expansion joint at one end of the new bridge following rapid design and fabrication at mageba’s factory in Shanghai and air freight to New Zealand