How wind affects vehicles crossing a double-deck suspension bridge
Sejin Kim, Jae-Hong Shim, Ho-Kyung Kim
Abstract
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.