Title A tool for evaluating whole of life costs of rail bridge renewal options
Author Wood, S
White, M
Grave, S
Conference AusRAIL PLUS 2013, Driving the Costs out of Rail, 26-28 November 2013, Sydney, NSW, Australia
Publication Date 2013
Location Server
Abstract Consideration of whole of life costs, rather than only initial capital outlay is preferable when selecting the best option for long life assets such as rail bridges and structures. Until recently KiwiRail lacked a robust means of determining whole of life bridge costs and benefits. This paper outlines a spreadsheet-based evaluation tool developed by AECOM for KiwiRail, which enables the assessment of all costs and benefits for different bridge renewal options over a 60 year evaluation period. The evaluation tool was initially used to assess bridge renewal options on a 30km section of the North Island Main Trunk (NIMT) railway, but has subsequently been applied to other KiwiRail bridge renewal projects. The outcome was a robust process for determining the preferred renewal option for each bridge. The cost benefit evaluation tool also identified that total replacement of bridges approaching life expiry is a better financial investment than either managing deteriorating asset condition through maintenance and operating regimes, or the progressive renewal of components. In addition, ballast deck bridges, although more expensive to construct, perform better than direct fastened span bridges due to lower track maintenance costs. Offline alignments were generally not justifiable in terms of transit time savings, but may be preferred in some cases from a constructability perspective. This provides confidence to internal and external stakeholders that investment decisions are being considered from a holistic perspective, taking into account KiwiRail’s mandate to run a commercially sustainable rail business, as well as long term asset stewardship needs. It also allows visibility of the impacts of either cheapest initial cost or optimal whole of life cost investment policy decisions.
File - click thumbnail to download
8. Simon Wood, AECOM
Subjects Bridge maintenance
Asset management
Life cycle costs
Cost benefit analysis