桩式丁坝局部冲刷深度试验研究  

Experimental Study on Local Scouring Depth of Permeable Pile Groin

作　　者：周银军[1,2] 陈立[2] 刘金[2,3] 许文盛[2] 

机构地区：[1]长江科学院河流研究所,湖北武汉430010 [2]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072 [3]中国长江三峡集团公司,湖北宜昌443000

出　　处：《应用基础与工程科学学报》2010年第5期750-758,共9页Journal of Basic Science and Engineering

基　　金：国家科技支撑计划项目(2006BAB05B03-05);国家自然科学基金项目(10672125)

摘　　要：针对桩式丁坝局部冲刷特性及其最大冲刷深度,在总结前人研究的基础上,进行了桩式丁坝清水冲刷动床试验.试验中挑角范围在30—135°之间,透水率范围在0—40%之间,通过试验分析了其冲刷坑形态,冲刷深度影响因素和机理.研究结果表明:桩式丁坝局部冲刷坑呈"V"形槽状,最低点位于桩根附近,整个冲刷槽最大冲刷深度位于坝头,由绕坝水流所导致.冲刷深度随河宽缩窄率增大而增大,随透水率增大而减小,正挑时丁坝的冲深最大,同时还与Fr和床沙级配有关.最后,通过量纲分析建立了非淹没桩式丁坝局部最大冲刷深度的计算公式,该式将桩式丁坝冲刷深度与其影响因素直接联系起来,能够定量反映其影响规律,其计算结果与试验数据符合良好,可为实际工程设计提供参考依据.In case of the law of local scour and calculation of the maximal scouring depth associated with permeable pile groin,the mobile bed experiment of clear water scouring with different operating conditions was carried on.In the experiment,the groin models were angled from 30° to 135° to the downstream channel sidewall with six pervious rates between 0 and 40%.Based on the experiment and previous research,the shape of the scouring hole,the influential factors and mechanism of local scour depth about the permeable groin were researched.The conclusions of this research showed that the local scour hole was a channel which looked like a ＂V＂,the scouring depth nearby the pile root was maximal,and in the whole local scour channel,the maximal scouring depth was situated at head of groin and caused by circumferential motion around piles.The depth was augmented with the contraction ratio increasing,and also with the pervious rate decreasing,especially when the angel was 90° the depth was maximal,which also related with Fr and sediments gradation.At last,dimensional analysis was used to derive the calculated formula about local scour depth of permeable pile groin,the formula connected the depth and its influence factors directly,and it can reflect the influencing law quantitatively.The calculated results fitted the experiment data well,which could supply reference to the project design.

关 键 词：桩式丁坝 冲刷槽 冲刷深度 透水率 

分 类 号：TV143[水利工程—水力学及河流动力学]