ABSTRACT
The root cause of several worldwide bridge collapses in the past 20 years has been identified as resulting from the poor performance of structural details known as halving joints. Concrete halving joints are renowned for their low redundancy, potentially brittle failure characteristic (if not detailed correctly), and high stress concentration zones. Best practice management of these details involves both structural assessment and inspection with information from both contributing to the overall assessment. This research presents the results of the analysis of the strand development length effect on the behaviour of halving joints on pre-tensioned girders. A conventional strut-tie analysis of these joint revealed that their capacity is controlled by the development characteristics of the pre-tensioned strand. Based on this analysis, the most vulnerable bridge on the network was identified. Non-linear advanced finite element analysis demonstrated that the strand development did severely limit the halving joint capacity and that this mode of failure had not been anticipated by the designers. This knowledge allowed the management of these bridges to be improved by modifying inspection regimes to include the likely crack locations for this failure mode.
