Next Generation Earthquake-resilient Precast Concrete Bridges in a Changing Climate

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The 2019 Canada Infrastructure Report Card makes it clear that the rapid aging of Canada's bridges is alarming. As of 2019, the percentage of Canadian bridges that are in `poor' or `very poor' condition has tripled since 2016 to around 12%. Repairing or replacing these deteriorating bridges will cause significant traffic disruptions due to lane and/or road closures. As such, the need for adoption of Prefabricated Concrete Bridge Elements and Systems (PBES) through Accelerated Bridge Construction (ABC), which can offer tremendous savings in construction time, is greater than ever. However, the deployment of PBES has been limited to low-seismicity areas due to the lack of seismic design guidelines. Knowledge gaps on PBES durability, which is largely influenced by environmental exposure, also slow down the adoption of PBES. Climate change is expected to accelerate the deterioration rate, creating additional uncertainty in the durability of PBES. To tackle the above challenges, the proposed research program aims to enhance the resilience of PBES that are exposed to both episodic (earthquake) and chronic (corrosion in the context of climate change) hazards. To fulfill this goal, the research will take advantage of advances in materials science by utilizing Ultra-high-Performance Concrete (UHPC) with exceptional mechanical and durability properties. Over the next five years, the research will make the following unique contributions: 1) Develop seismically resilient PBES by using UHPC-based low-damage connection technologies and by proposing quantitative seismic damage states. 2) Characterize corrosion-related deterioration for PBES under a changing climate, and investigate UHPC to enhance the corrosion resistance of PBES. 3) Create an analytical framework to assess the climate change impact on the lifetime seismic vulnerability of PBES. The research will advance the state-of-the-art of seismic and climate resilience of PBES by generating high-quality test data, developing validated computational methods and design tools, creating Canadian `corrosion' hazard map, and developing UHPC-based solutions for seismic damage control and climate change adaption. The developed quantitative seismic damage states will assist Canadian Highway Bridge Design Code in adapting performance-based seismic design for PBES. By incorporating future climate conditions, the lifetime prediction methods will improve the service life design of PBES for sustained serviceability and seismic safety. Bridge designers and owners will benefit from the research for seismic design and decision-oriented long-term performance evaluation for PBES. This is much needed to unlock the potential of ABC for bridge repair and construction in seismic areas of Canada that are also affected by climate change. HQP will be trained in advanced bridge design and construction techniques, and become important contributors to build and maintain safe and sustainable bridge infrastructure for Canadians.