波流作用的近岸圆柱局部床面侵蚀  

Solitary wave scour around a cylinder in shoaling conditions

作　　者：齐梅兰[1] 李金钊[1] 郐艳荣[1] 

机构地区：[1]北京交通大学土木与建筑工程学院,北京100044

出　　处：《水利学报》2015年第7期783-791,共9页Journal of Hydraulic Engineering

基　　金：国家自然科学基金资助项目(51078021;50778018);高等学校博士学科点专项科研基金资助项(20100009110016);中央高校基本科研业务费项目(2013YJS065)

摘　　要：波浪流对近岸浅水带床面作用强烈,该区域结构物局部床面侵蚀显著,潜存致灾威胁。用三维数值方法研究了瞬态孤立波作用下非黏性沙海床上的近岸圆柱体局部冲刷规律,分析了波浪流冲刷的3类主要影响要素,讨论了近岸地形条件影响下的波流冲刷深度。研究认为,表征浅水波流特征和柱体尺度的无量纲数Urp与KC数存在非独立关系,二者均能分别反映波流冲刷的主要规律;表示泥沙运动的力学参数Shields数在波流动床条件下仍对柱体局部冲刷有贡献;近岸地形通过床面坡度对波破碎的增强及堤岸挡墙对波浪的反射,都会影响到局部冲刷。Solitary wave attack causes substantial erosion and significant local scour around cylindrical struc- tures in nearshore shallow water conditions. The transient wave scour around a coastal cylinder on noncohe- sive sediment seabed was investigated by three-dimensional numerical method. Three kinds of influential fac- tors on wave flow scour were identified. In addition, the maximum scour depths in different coastal topogra- phy conditions were analyzed. The results show that either modified Ursell （Urp） number or Keulegan-Car- penter （KC） number, representing the ratio of wave characteristic and cylinder scale, governs the maxi- mum scour depth. Furthermore, the dependent relationship between these two numbers was also obtained. In live-bed conditions, the Shields parameter of sediment still contributes to the local scour of the cylin- der. The offshore seabed slope and embankment wall have effects on wave breaking and wave reflection re- spectively, which therefore influence the scour depth.

关 键 词：冲刷 圆柱 孤立波 近岸带 波破碎 

分 类 号：TV142[水利工程—水力学及河流动力学]