Management of Structures with Concrete Halving Joint

Abstract

The root cause of a number of international bridge collapses in the past 20 years has been identified as resulting from the poor performance of structural details known as halving joints. While the Department of Transport & Main Roads (TMR) no longer allow this type of detail, they were considered acceptable for many years, and are not uncommon on the TMR/State network. Structures with concrete halving joints are renowned for its low redundancy and potentially brittle failure characteristic (if not detailed correctly) and higher stress concentration zones. Detailed research has been undertaken during the past 20 years (notably in Europe) to understand and quantify the behaviour of these details. As a responsible asset steward, TMR are currently undertaking a project titled Management of Structures with Concrete Halving Joints which involves: 1. A network review to identify all concrete halving joint bridges 2. Preliminary safety risk ranking of identified bridges 3. Detailed inspection, starting with those considered to represent greatest network risk, using the recent research to understand the performance of TMR halving joints and quantify resulting risks 4. Interventions, such as strengthening to identified structure/s if deemed appropriate. 5. Identify and prioritise bridges with these structural components in order to develop a 'fit for purpose' risk management and maintenance strategies to ensure ongoing safe operation of these bridges. This presentation will provide an overview of the project, followed by a discussion of key learnings to date, and also discuss likely scenarios for addressing these details on the remainder of the network.