CLIENT: Main Roads WA
Contract: 55/14 Construct Only
TIMEFRAME: December 2015 – June 2016
VALUE: AUD$2.7 million
Highway Construction together with their joint venture partner Albem Operations delivered complex bridge strengthening works using innovative methods and techniques not previously seen in Western Australia.
Prior to works, increasing volumes of traffic on Roe Highway, particularly an increase in heavy vehicles as a result of the WA mining boom, had been taking its toll, and the bridge was in a poor state of repair. Main Roads WA had designated the bridge for urgent strengthening works and had placed a 10 km/hr restriction on heavy vehicles traveling over the bridge until works were completed, causing significant traffic congestion for the 60,000 vehicles using the bridge each day.
The design phase, undertaken by AECOM (the structural designer) in collaboration with Main Roads WA had identified the optimum bridge strengthening solution to involve the installation of additional bridge beams (steel girders) and columns (steel columns).
The beams would be supported by a micro-piled foundation solution, now generally the preferred foundation solution in Western Australia due to its eco-friendly cost saving properties.
However, the use of steel girders with micro-piled foundations was the first time this methodology had been used in bridge strengthening works for an existing structure in WA. As such, it would present a number of challenges for the constructor, as no construction precedents existed.
Working in partnership with Main Roads WA, the Highway Construction /Albem Operations JV (HAJV), was able to safely overcome these key challenges: whilst also working within a complex program of activity performed within a tight work area; without disrupting traffic flow; and whilst also respecting the environmental integrity of the area.
The safety system adopted was also commended during 3rd party auditing from the Office of the Federal Safety Commissioner and later by Main Roads’ and our own internal safety, quality and environmental audits. This was achieved using a combination of: a highly flexible and experienced approach to project management; advanced programming and traffic management ability; open two-way communication with the Client; innovative thinking in the development and application of specialised materials; and advanced construction techniques.
The end result was a project that met all agreed timelines, underspent on the Client’s budget, and which has set new benchmarks in the delivery of similar works into the future.
Equally as important, the successful completion of these works meant no further restrictions on the bridge for oversize vehicles resulting in an immediate decrease in traffic congestion and improvement in amenity for the traveling public and freight users.