Management of fatigue cracking: West Gate Bridge, Melbourne

Abstract

Melbourne’s West Gate Bridge has recently been the subject of a major, award-winning strengthening project designed to increase load capacity and reduce maintenance requirements. This paper addresses the management of existing and potential fatigue cracking on the steel spans of the bridge. Recent growth in average vehicle weight and traffic volumes has continued to give rise to fatigue cracking, something the bridge has suffered from since soon after it was opened, particularly in areas directly subject to wheel and axle loads. The paper summarises the work being undertaken on the fatigue-prone areas and focuses on crack monitoring and behaviour. It also describes the fatigue management task, treatment details, constructability issues and the strategy for prioritising the treatment works.