【摘 要】
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This study performed a bridge pier collar comparison for the purpose of reducing scour, while intro-ducing a new collar design. The new collar, referred to as Collar Prototype Number 3, was designed based on an equilibrium scour hole and provides a method
【机 构】
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Department of Civil Engineering,University of Ottawa,161 Louis Pasteur Drive,Ottawa,K1N 6N5,Canada
论文部分内容阅读
This study performed a bridge pier collar comparison for the purpose of reducing scour, while intro-ducing a new collar design. The new collar, referred to as Collar Prototype Number 3, was designed based on an equilibrium scour hole and provides a method of controlling the horseshoe vortex. Numerical modelling was utilized to show the flow field and bed shear stress as a result of using Collar Prototype Number 3. A prototype model of Collar Prototype Number 3 and a flat plate collar were constructed for the purpose of comparing both experimentally under different flow conditions. Collar Prototype Number 3 proved to be an effective device as it reduced scour in terms of the maximum depth downstream of the pier and overall volume, in some instances, by up to 69.7％and 75.7％, respectively. Furthermore, Collar Prototype Number 3 outperformed the flat plate collar, especially because, unlike the flat plate collar, Collar Prototype Number 3 did not experience undermining.
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