P07: Assessment of Seismic Performance Mitigation Technique for Enhancing the Safety and Serviceability of Existing Transportation Infrastructure in the UAE

This study is directed at selecting an effective mitigation measure to enhance the seismic performance and ensure the functionality of transportation infrastructure represented by a benchmark multi-span bridge in the UAE. A three-dimensional (3D) numerical model is developed for the entire bridge, which enables estimating the lateral load-carrying capacity of the bridge and its bents using inelastic pushover analysis. Dynamic time history analyses are also carried out by applying input ground motions representing the study area to predict the seismic demands of the bridge. The incremental inelastic analysis and dynamic response simulation result highlight the structure's vulnerability and the need for upgrading its seismic performance. A retrofit measure using ultra-high-performance concrete (UHPC) jackets is thus proposed and implemented in the 3D simulation model of the multi-span bridge. The results illustrate that the adopted retrofit measure effectively reduces the deformation demands and the lateral strength of the bridge substructure is enhanced by a factor of one-third. The study reflects the pressing need for more seismic performance assessment and mitigation studies to ensure better safety and the uninterrupted operation of substandard transportation infrastructure in the aftermath of earthquakes.