Impact of climate change in geostrutures with particular reference to transport infrastructure

Current performance shortcomings in the transport infrastructure formations induced by extreme climatic events cause excessive maintenance requirements with increased costs and disruptions to commuters and loss of productivity in the freight services. This PhD project aims to explore the impact of climate change in compacted geomaterials incorporated in the transport infrastructure substructure formations. While the infrastructure developed in the last 60 years has been built following the principles of compaction, much of the UK transport infrastructure was built before those principles were understood and practiced and thus particularly vulnerable to increasingly severe changes in hydraulic stresses caused by climate as well as degradation of its properties due to increasingly higher traffic demand, e.g. increase in dynamic stresses as a function of speed and axle loads.

The project will focus on the study of the role of the seasonal variation in hydraulic stresses (i.e. matric suction) that compacted geomaterials undergo during their service life, in particular the performance shortfalls for different compacted states including old infrastructure under-compacted conditions. It will also aims to study the impact of extreme climatic events (e.g. flash flooding accompanied by periods of intense rainfall and extended period of droughts) and the role of vegetation in curbing those impacts. It will involve advanced laboratory testing and modelling focussing on the water retention behaviour of compacted materials and monotonic and dynamic stress-strain behaviour simulating typical transport infrastructure conditions.