How wind affects vehicles crossing a double-deck suspension bridge

• Published in: Journal of wind engineering and industrial aerodynamics 2020-11, Vol.206, p.104329, Article 104329
• Main Authors: Kim, Se-Jin, Shim, Jae-Hong, Kim, Ho-Kyung
• Format: Article
• Language: English
• Subjects: Aerodynamic coefficients; Double-deck bridge; Vehicle stability; Wind-tunnel test; Winds
• ISSN: 0167-6105; 1872-8197
• DOI: 10.1016/j.jweia.2020.104329

In this study, wind-tunnel testing was used to evaluate how side-winds interact with the geometric characteristics of the truss girders of a double-deck bridge and how this impacts vehicle stability. The aerodynamic coefficients of three vehicle types—sedans, trucks, and tractor-trailers—were obtained using force-balance sensors placed on each traffic lane and deck. The two girder shapes of the main and approach spans were tested for an in-depth assessment of the effects of the structural and nonstructural components and the geometric characteristics of the girder composition. A double-deck suspension bridge in South Korea was selected for the case study because two consecutive accidents that involved the overturning of two vehicles occurred on the approach span of this bridge in 2012. The test results provided evidence as to why these two accidents had occurred on the approach span rather than on the main span. Several features unique to double-deck truss girders were investigated. The novel findings from this study provide valuable insight into the wind hazards encountered by vehicles crossing a double-deck bridge. •The aerodynamic forces acting on vehicles on a double-deck suspension bridge were measured via wind-tunnel testing.•Three types of vehicles—sedans, trucks, and tractor-trailers—were considered.•The lower deck of the approach span was the most vulnerable to upcoming wind owing to the wind-tunneling effect.•The truss members in the main span provided a screening effect that protected the vehicles in the lower deck.•These findings explain the likely causes of two consecutive accidents on the approach span.