Strategic asset management modelling of infrastructure assets

Network Rail owns tens of thousands of civil engineering assets in the UK which include more than 40 000 bridges, 15 000 km of earthworks and 200 km of sea defences. In order to manage this diverse and ageing infrastructure a model was required to forecast the level of expenditure needed to meet defined levels of service that recognises the variation in types of asset, individual condition and the intensity of use of each asset. The model allowed Network Rail to plan its programme of maintenance work on civil engineering assets to achieve long-term objectives and provided essential information in preparation for periodic submissions for funding to the Office of Rail Regulation. Recognising that each asset could be managed in a number of ways, Mouchel provided modelling support to forecast the expenditure and performance implications for a range of policies. By selecting the policies to be applied to different groups of structures, Network Rail was able to investigate the implications of applying different combinations of policies to groups of assets, or assets on specific railway routes. This enabled Network Rail to identify a preferred maintenance approach according to funding levels and immediate performance requirements with full recognition of the long-term implications. The models utilised Bayesian statistical methods to deal with the large number of assets and optimising routines to ensure that structures were managed efficiently over the long term.