Briefing: Bridges at risk from multi-hazards

Multi-hazards caused by heavy rainfall such as landslides, debris flows and floods have become major threats to infrastructures like highway bridges. This paper summarises failure types and genetic causes of highway bridge damage during typhoon Morakot which invaded Taiwan in 2009. Most bridges suffered the combined effects of at least two kinds of hazards: bridges located in the upstream area were mostly destroyed by debris and landslides; those located in the downstream areas were damaged by outsize floods and scours. Endorsements on improving design and risk analysis of highway bridges are proposed in an effort to provide engineers with fundamental approaches when facing challenges of extreme climate.