Résumé | An appraisal of historical and recent damage to bridges in Canada and internationally underlines the risks posed by water loads, scour and ice effects. More than 50% of bridge failures in North America are attributed to floods and hydraulic factors, including scour, debris impacts and ice effects. River ice is a unique challenge for bridges in northern climates, with estimates of annual average damages in Canada due to ice jams exceeding $100 million. The rising costs and damages associated with extreme weather events highlight the vulnerabilities of Canadian infrastructure to climate change. Potential changes in exposure to ice and flood hazards (from riverine, pluvial, and coastal sources) pose a threat to the integrity and sustainability of transportation infrastructure, including bridges and overpasses. The Canadian Highway Bridge Design Code contains provisions for evaluating water loads, scour and ice action for new bridges, and refers to the Transportation Association of Canada’s (TAC) Guide to Bridge Hydraulics for additional guidance. However, there are no provisions for evaluating potential climate change impacts on these loads and actions. A review of the current state of bridge design practice for evaluating, mitigating and adapting to water loads, scour, ice action and related climate change impacts was conducted. This included an appraisal of bridge design codes, standards and guidelines in Canada and other countries. The review identified current gaps, emerging best practices, and possible steps towards improving design guidance and the resilience of Canadian bridges and overpasses to water loads, scour, ice action and climate change. |
---|