An Over-Height Collision Protection System of Sandwich PolymerComposites Integrated with Remote Monitoring for Concrete BridgeGirders

One of the common damages in existing highway bridges is the damage at the bottom corners or edges of the reinforced concrete beams or box girders induced by an impact of trucks exceeding the allowable height clearance of the bridges. In this study, a collision protection and scarifying system is developed, and it utilizes advanced materials/structures to protect highway bridge girders. The proposed collision protection and scarifying system is in a new “I-Lam” (Impact Laminate) configuration and bolted and/or bonded to the bottom portions or edges of concrete girders. The I-Lam panels are made of a composite sandwich construction with multi-layer aluminum honeycomb core and top and bottom thin face sheets, and they are developed/designed specifically for impact damage protection of bridge girders (e.g., concrete girders). Design criteria and guideline for I-Lam are developed, and the analysis, optimal design, and quality control tests of the collision protection system are conducted. Smart piezoelectric sensors are integrated with the I-Lam panels for monitoring the performance of the collision protection system. The collision protection system is implemented in an identified bridge. The developed smart bilayer honeycomb I-Lam sandwich is capable of reducing the transferred contact force dramatically, absorbing/mitigating impact energy, protecting the underneath concrete structures by system scarifying and core crushing, and monitoring the impact incident with smart piezoelectric sensors, and it is applicable to protecting other structures (e.g., steel girders, columns) from accidental vehicle impact in the highways.