Improvement of pavement design and management for more frequent flooding caused by climate change

Climatological records show a trend of the increasing occurrence of extreme weathers caused by global climate change. One form of extreme weathers is heavy rainfall which, combined with rising sea levels, made highways in some subtropical regions susceptible to flooding. Flooding in these regions causes noticeable damages to flexible highway pavements. However, little research has been conducted to quantify such damages and develop possible mitigation measures. This study developed a method to incorporate flood risk into the structural analysis of flexible pavements, examined the effects of flooding on pavement materials and structures through laboratory tests and design simulations, and recommended better pavement design and management strategies. Flexible pavement is found to be significantly affected by flooding. Future climate change and the resultant increase of flooding frequency pose a serious challenge to the reliability of flexible highway pavements. To mitigate the detrimental effects of flooding, pavement thickness and drainage system need to be adequately designed and post-flood traffic control may need to be imposed.