Bridges

In 2008, the Roads and Traffic Authority (RTA) of New South Wales(NSW) advised all contractors to improve workmanship quality across all RTA construction projects. This followed the discovery that many structures, including bridges, were not being constructed to meet whole-of-life performance, resulting in high maintenance and repair costs. Issues included concrete cracking and poor ride quality. In response, the Ballina Bypass Alliance (BBA) set out to achieve above industry standard for bridge deck construction. BBA introduced a program to increase quality through regular workmanship inspections by independent experts, and set key performance indicators on bridge deck cracking and coefficient of variation (CV) of concrete strength. Learning from previous projects and planning in identified target areas led to above average outcomes, and use of some industry-leading measures, including vibrating truss screed, mobile access gantry, and wet curing for seven days. Overall, the BBA concrete bridge decks were rated 4 out of 5 for crack severity per span (‘good’), and 5.1% for CV of mix (‘outstanding’). These signify the BBA team has provided a product that will last its intended 100-year design life, while lifting workmanship beyond ‘business as usual’ for previous concrete bridges in NSW.