Risk assessment of deteriorating infrastructure in a changing climate

The estimation of failure risk of core public infrastructure due to natural hazards is of much interest to owners and operators of these assets. The challenges involved are exacerbated by the expected changes in climatic loads and infrastructure deterioration. Estimating failure risk must consider simultaneously the loads imposed by the natural hazard and the capacity of the infrastructure asset to resist such loads. Both the loads and the capacity to resist are non-stationary in time, loads due to climate change and capacity to resist due to deterioration. The literature reflects a significant body of work on estimating risk from natural hazards but only a minor effort to consider both non-stationary loadings and non-stationary capacity to resist these loadings. This paper presents an approach to consider both non-stationary drivers simultaneously. The proposed approach does not limit the user to a specific asset deterioration model or a specific hazard loading model, as long as both can be Discretised in a certain manner. The proposed approach can be applied qualitatively (for low-priority assets), semi-quantitatively (for high priority assets) or fully-quantitively for assets of national importance. Moreover, the proposed approach is intuitive and easily lends itself to programming using spreadsheets or dedicated programs.