Gateway WA Perth Airport and Freight Access Project is Western Australia’s largest ever road project, at a cost of $1 billion. Gateway WA aims to create an iconic gateway to the state, as well as improving the safety and efficiency of one of WA’s most important transport hubs. This significant project is jointly funded by both the Federal and Western Australian Governments, and delivered by an alliance of partners.
The project incorporates construction of 165 kilometres of road, seven underpasses, seven kilometres of noise walls, thousands of square metres of retaining walls, numerous ancillary precast elements and 11 major bridges. Precast concrete was an essential component of the build. Of the 11 bridges, seven have been constructed using TeeRoff precast prestressed concrete beams, while four used precast pre-stressed concrete planks.
Perth-based precast concrete manufacturer and National Precast member Delta Corporation Ltd was contracted to supply precast concrete for parts of this significant infrastructure project.
The precaster supplied TeeRoff beams, parapet panels, earth retaining wall panels and Deltacore floor planks. All these elements were manufactured at Delta’s precast factory in Herne Hill.
According to Delta Executive Director Matt Perrella, the company’s expertise is well recognised in the civil construction industry. “Our state-of-the-art facilities and high capacity prestressing beds cater for varying component sizes and high volume,” he says.
“Precast was chosen for this project because of its structural quality and the speed of construction. It’s simply more efficient to manufacture off site. In this case it was less expensive and it also ensured there was minimal disruption to traffic,” Mr Perrella adds.
The precaster manufactured 86 TeeRoff beams in varying sizes ranging from 75 to 168 tonnes each for the project. The largest beam weighed 168 tonnes, with dimensions of 39.5 metres long, 4.85 metres wide and 1.6 metres thick. These beams are the heaviest Delta has ever produced.
Two of the major Gateway WA bridges support single point urban interchanges to ensure efficient movement of the large traffic volumes involved. The larger of these bridges utilises 26 TeeRoff beams for the major part of its width, and a combination of precast and in-situ concrete for the flared edges. In addition, Delta manufactured 1916 square-metre retaining wall panels, parapet panels and more than 1000 square-metre Deltacore floor planks and parapet panels for this project.
The Gateway WA Project aims to standardise design throughout the project as much as possible. But each bridge needed to meet distinctive requirements that called for customisation.
To meet the varying constraints across the project, precast was ideal to accommodate varying foundations and support conditions.
The delivery program for Gateway WA is planned in a staged approach to minimise disruption to the community and road users. As a result of this staged approach, Delta completed the final delivery of the TeeRoff beams 10 months ahead of schedule.
The full scope of works is due for completion by the middle of 2016.