环翼式桥墩防冲板类型优选试验研究  

Experimental study on optimization of the type of ring-wing anti-scour panels in pier

作　　者：李春江[1] 牟献友[1] 王祚[1] 田剑浩 陈艳梅[1] 

机构地区：[1]内蒙古农业大学水利与土木建筑工程学院,呼和浩特010018

出　　处：《中国科技论文》2015年第7期846-850,共5页China Sciencepaper

基　　金：国家自然科学基金资助项目(51369022);内蒙古自治区自然科学基金资助项目(2013MS0719)

摘　　要：为选出最有效的桥墩防冲板类型,通过用椭圆标准方程对防冲板形状进行控制,优选出20个整幅和20个半幅2种类型防冲板,再以最大冲坑深度、三维流速变化和三维紊动变化为试验指标,定量分析整幅和半幅2种类型防冲板的防冲效果,并优选出最佳防冲板类型。试验结果表明:整幅和半幅防冲板防冲刷作用明显比无防冲板工况好,且当防冲板长、短半轴都等于2R时,整幅和半幅防冲板冲坑深度减小率最大,分别为51.6%和57.9%;加上整幅或半幅防冲板后,桥墩周围的纵向和垂向流速分布受到明显影响,且在半幅工况下墩前河床近底流速(防冲板以下)要比整幅工况小;在整幅和半幅防冲板以下部分,纵向和垂向紊动强度变化较大,而横向紊动强度没有发生大幅度变化,相同水深处整幅防冲板工况下的纵向紊动强度比半幅的大,由此得出半幅防冲板更利于桥墩防冲刷的结论。In order to select the most effective prevention panels type, by using standard equation of the ellipse to control shape of anti-scour panel, 20 whole anti-scour panels and 20 half anti-scour panels are selected. Taking the maximum scour depth, three- dimensional velocity change and three dimensional turbulent changes as the test index, quantification ally scour prevention effect of whole panel and half panel were analyzed, and the best scour prevention panel type was determined. The results show that the anti-scour effect of the whole anti-scour panel and the half anti-scour panel are significantly better than the effect of non- panel. In addition, when a-values and b-values are 2R, the maximum scour reduced rates of the whole anti-scour panel and the half anti- scour panel are the largest, with their respective values being 51. 6% and 57. 9%. On the same condition, the maximum scour depth reduction rate of the half anti-scour panel is slightly larger than the reduction rate of the whole panel, and the difference between the two kinds is reduced from 4. 2% to 10. 5%. After installing the whole anti-scour panel and the half anti-scour panel, the distribution of the longitudinal and vertical velocity around the piers is significantly affected, and near-bottom velocity of the half panel is smaller than near-bottom velocity of the whole panel below the anti-scour panel, and the half type is better. Under the whole anti-scour panel and the half anti-scour panel, the longitudinal and vertical turbulence intensity changed greatly, and when the depth is the same, the whole panel is larger than half panel in longitudinal turbulence intensity below the anti-scour panel, so the half panel is more advantageous to the pier scour.

关 键 词：局部冲刷 环翼式防冲板 流场特性 紊动强度 

分 类 号：U443.26[建筑科学—桥梁与隧道工程]