A review of energy-dissipating systems for over-height vehicle bridge impact mitigation

This review addresses the critical safety challenges posed by collisions between over-height vehicles and low-clearance bridge girders, an underexplored topic in impact research. These collisions can lead to significant infrastructure damage, economic losses, and transportation disruptions. This paper synthesises experimental, numerical, and analytical studies on unprotected and protected structural members, focusing on the effectiveness of energy-absorbing protective systems. It highlights the limitations of current design standards that rely on equivalent static forces (ESF) and advocates for a better understanding of dynamic impact behaviour. Further, it also investigates the performance of various energy-absorbing materials that shield structural components from different impact types to identify and implement the most effective cushion systems for the impacts under consideration. The review identifies gaps in the existing literature, particularly in the interaction dynamics between over-height vehicles, cushioning devices, and bridge girders, and suggests future research directions to advance protective systems for infrastructure safety.