Assessment of the impact of climate change on road maintenance

Climate affects road deterioration, vehicle operating costs, road safety and the environment. Current and past pavement design guides and engineering models assume a static climate whose variability can be determined from past data. This fixed climate assumptions is often used in road management decision support models such as the Highway Development and Management system (HDM-4) to simulate future behaviour of road sections and consequently inform long-term road maintenance strategies and policies. Contrary to the assumption of a static climate in road management approaches, observations over the last 40 or 50 years show increasing trend in global warming. This raises the possibility that the severity and frequency of pavement defects may be altered leading to premature pavement deterioration and increased costs of managing and using roads. As a consequence, current road management strategies and policies may not offer sufficient resilience to increased frequency of future extreme climate events. A study was undertaken at the University of Birmingham to develop improved deterioration model for asphalt rut depth prediction. The approach used entailed the application of Bayesian Monte Carlo analysis. The output of the study will be used to improve existing road management systems such as HDM-4 and to consequently facilitate the investigation of strategies for adapting to future changes in climate