Bridges

As the freight demands on road corridors and heavy vehicles masses increase, there is a need to quantify the impact of these vehicles and manage the risks on ageing infrastructure assets, especially bridges. To help manage this risk, structural performance monitoring (SPM) is an option that can be used where instrumentation is installed on structures to provide insights on bridge performance.

Using SPM data from controlled diagnostic load testing of an instrumented bridge, it is possible to obtain the influence lines for the structure. These influence lines are a useful property to determine insights such as magnitude of strain or deflections at key points of the structure to any heavy vehicle seeking access to the network.

The derived influence lines also facilitate the adoption of more modern and advanced bridge assessment frameworks than currently prescribed in Australian Standard (AS) 5100.7. The outcomes from these frameworks allow the potential to explore changes to the operational policy on heavy vehicle access, such as choice of dynamic load allowance factors. Advanced bridge assessment methods include bridge-specific assessment live loading (BSALL) and probability-based bridge assessments (PBBA) adopting the tenets of AS 5104.

This paper discusses some theoretical background and use of data from SPM systems for advanced bridge assessment frameworks. Preliminary results and progress thus far are discussed for a multi-year initiative by the Victorian Department of Transport and Planning (DTP) exploring SPM installations on certain bridges along a key road corridor on the state for managing access of high-productivity freight vehicles (HPFVs).