Bridges damaged during the 2019 Poldokhtar flood: towards flood-resilient bridges

Abstract

Bridges are among the most vital parts of infrastructure networks in every country, and have been seriously damaged by natural hazards such as floods and earthquakes in the past. Engineering communities have always faced challenges protecting these structures from flood hazards. Today, the world is facing climate change, with incidences of severe floods increasing globally. Flooding brings the possibility of significant bridge damage and therefore studying bridge performance under flood hazards is of vital importance. The flood in Poldokhtar, Iran, in 2019 was one of the most destructive floods in the last decade. In this research, the performance of 14 bridges during the Poldokhtar flood was reviewed and the damage incurred was assessed through field investigations. The aim of this paper is to demonstrate, based on visual inspections and engineering judgement, the different reasons and scenarios that lead to the destruction of different types of bridges during floods. The results of this study emphasise the need to estimate bridge vulnerability and develop procedures to prevent bridge destruction. The technical and statistical information on bridge destruction due to flooding obtained in this work is vital for the management and inspection systems of bridges, the retrofit of existing bridges and the design of new flood-resilient bridges.