Bridge post-disaster rapid inspection using 3D point cloud: a case study on vehicle-bridge collision

Abstract

With the increase in traffic volume, vehicle-bridge collision accidents have been more frequent, creating significant threats to the safe operation of bridges. In the face of sudden vehicle collision accidents, bridge management agencies urgently require fast and accurate damage inspection methods to assess the service performance of the damaged bridge and provide support for post-disaster recovery. However, the service performance of a bridge is related to its overall structure and localized damage morphology. It is challenging for traditional measurement methods to obtain the three-dimensional (3D) morphology of the bridge and damaged areas. They can only obtain limited data points, which cannot provide adequate data for bridge damage assessment. Recently developed 3D laser scanning technology has guaranteed an accurate and timely 3D morphology inspection for the damaged bridge. Based on 3D laser scanning technology, this research proposed a post-disaster emergency inspection solution using a vehicle-bridge collision accident as a practical case, which provides a basis for emergency response decisions. This study focused on the rapid acquisition of the bridge digital model, spatial morphology identification of bridge components, and refined assessment of collision damage. The inspecting results revealed anomalies in the elevation of the damaged main girder and main cable, which necessitated urgent reinforcement measures. Additionally, the damaged hanger was found to have exhibited a lateral deflection angle of 17.12°, with a maximum cable clamp damage depth of 33.06 mm, requiring immediate replacement.