Assessment of the existing structures presented unique challenges that necessitate special consideration. The key challenges include catastrophic failure risk, evolving design standards and limited historic records.
The problem we were asked to solve
The National Transport Research Organisation (NTRO) was engaged by the National Heavy Vehicle Regulator (NHVR) to undertake Tier 1, 2 and 3 asset assessments and Level 3 investigations to supplement the tier assessments for the Strategic Local Government Asset Assessment Project (SLGAAP) during Phase 1 (2020–21) and Phase 2, Round 1 (2022) of the project.
The SLGAAP is an Australian Government–funded initiative to optimise heavy vehicle access on the local road networks across Australia. The project supports council to better understand their asset capability by providing engineering assessments and informing heavy vehicle access decision-making.
The Australian Government provided the NHVR with $7.96 million under the Strategic Local Government Asset Assessment Project (SLGAAP) to assist road managers with the assessment of bridges and culverts on key local government heavy vehicle routes. Phase 1 of the project was administered between November 2019 and June 2021. Subsequently, the Australian Government announced the commitment of an additional $12.1 million in May 2021 for Phase 2 of the project to enable the continuation of project activities to be conducted from January 2022 to 31 October 2024. The NTRO successfully delivered the work under Phase 1 and Phase 2, Round 1 and has been selected as one of the engineering consultants to deliver Phase 2, Round 2 of the project.
What we found
Assessment of the existing structures presented unique challenges that necessitate special consideration. The key challenges include catastrophic failure risk, evolving design standards and limited historic records. Diverse road manager approaches, interpretation gaps and resource constraints further complicate access decisions. Despite these challenges, the NTRO successfully executed the project through cooperation and collaboration with road managers and the NHVR to improve heavy vehicle access on the road network by providing engineering recommendations advising the outcome of the assessment and the use of risk controls (such as conditions of travel) to promote access for nominated heavy vehicles. All information related to the production of assessments and analysis conducted (including modelling information) under this project was provided to the NHVR and relevant local governments for use.
This program offers significant performance benefits by transcending traditional assessments and embracing optimised outcomes. Instead of relying on conservative processes, it leverages a diverse range of assessment strategies, frameworks and methodologies. This approach equips decision-makers with a comprehensive toolbox, enabling them to tailor restrictions based on the precise investigation's depth and the observed structural performance.
NTRO’s structural expertise coupled with collaborative discussions with road managers ensure well-informed decisions that strike a balance between access optimisation and safety. By considering various risk control options and existing performance data, NTRO enabled the implementation of reasonable access restrictions that enhance the overall efficiency and safety of heavy vehicle operations on the road network. Moreover, the focus on engineering judgment and cooperation fosters a dynamic and adaptable approach, paving the way for continuous improvement and effective responses to evolving challenges.
This program offers substantial benefits by preventing unnecessary restrictions and optimising resource allocation. By tailoring recommendations to the level of investigation detail and observed performance, NTRO helped to avoid overburdening the road network with excessive limitations. An emphasis on avoiding reliance on theoretical ratings alone helps allocate resources where they are truly needed, preventing unnecessary investments in modifications or repairs. Overall, the approach leads to cost-effective decisions, maximising the utilisation of available resources while safeguarding against structural risks. By establishing a consistent framework for assessment and considering a range of factors, the program facilitates informed and prudent decision-making, leading to optimal performance and cost-effectiveness in managing heavy vehicle access on the road network.
The purpose of undertaking the various tiers of assessments is ultimately to make decisions about access and how this may affect cost/risk/performance setpoint for the asset. Using more collaborative Tier 1, 2, and 3 assessments for bridges and culverts, the efficiency of roads with regards to heavy vehicle access can be improved, resulting in significant cost reductions and improved performance. NTRO aims to facilitate this with our technical expertise and state-of-the-art resources.