Analysis and Monitoring on the Highway Bridge with Newly Constructed Link Slab Considering Thermal Effects

Joint failure, which causes leakage in bridge decks as well as deterioration in girders and substructures, is one of the most common concerns in highway bridges in the United States. Therefore, closure pours or link slabs have been considered as a solution to eliminate these joints. The link slab system in this study is designed for an overpass bridge in the state of Maryland to improve its durability and reduce maintenance costs. However, traditional link slab design requires the replacement of current bearings to elastomeric bearings with one fixed condition, while others use expansion bearings, to minimize the thermal stress generated in the superstructure. Theoretically, this action will increase the longitudinal movement of the deck while releasing the stress caused by thermal expansion or contraction in the material. This paper proposes a more economical method of replacing bearings by revising the sliding plate to match the designed boundary condition. Firstly, some background information and the finite element analysis of the overpass highway bridge with link slab under thermal loading would be described, which shows the general idea of this project. Then, the sensor validation and installation of the bridge were introduced, and finally, the monitoring system is established. Finally, the long-term monitoring system for the pilot bridge is introduced, and results from finite element analysis are validated by the measurement.