基于航槽冲刷效率的丁坝护底宽度确定方法  

Determining method for the bottom protection width of spur dike based on the scouring efficiency of waterway

作　　者：杨燕华[1] 王建军[1,2] 杨阳[1] YANG Yan-hua;WANG Jian-jun;YANG Yang(Tianjin Research Institute for Water Transport,Tianjin 300456,China;Tianjin University,Tianjin 300072,China)

机构地区：[1]交通运输部天津水运工程科学研究所,天津300456 [2]天津大学,天津300072

出　　处：《水运工程》2021年第9期113-119,共7页Port & Waterway Engineering

基　　金：国家自然科学基金项目(51979132);中央级公益性科研院所基本科研业务费专项资金资助项目(TKS190405)。

摘　　要：考虑丁坝护底可压缩一般性的无效冲刷范围,以达到增加丁坝有效作用效率这一重要功能,提出基于航槽冲刷效率的丁坝护底宽度确定方法。通过理论分析、数值模拟和物模试验研究,得到主要结论:丁坝有效作用效率系数为动床航槽单宽流量增值与定床航槽单宽流量增值的比值。建立了丁坝有效冲刷效率的计算公式,通过该公式可计算丁坝护底宽度。公式表明:丁坝的有效冲刷效率为常数;当护底从丁坝坝根一直护到航槽边缘、形成定床条件时,丁坝的有效冲刷效率可达到100%。采用该方法可合理确定护底的宽度,减小丁坝坝头的一般性无效冲刷范围、增加丁坝对航槽的有效冲刷效率,使工程作用后的航槽改善效果更好。Whereas the bottom protection of spur dike can compress the general ineffective scouring range to increase the effective action efficiency of spur dike,a method for determining the bottom protection width of spur dike based on the waterway scour efficiency has been proposed.The main conclusions are drawn as follows through theoretical analysis,numerical simulation,and physical model test research:the effective action efficiency coefficient of the spur dike is the ratio of the increase in the single-width flow of the movable bed waterway to the increase in the single-width flow of the fixed bed waterway.Calculation formula for the effective scouring efficiency of the spur dike is established,which can be used to calculate the bottom protection width of the spur dike.The formula shows that the effective scouring efficiency of the spur dike is constant;when the bottom protection is from the spur dike root to the edge of the waterway to form a fixed bed condition,the effective scouring efficiency of the spur dike can reach 100%.By this method,the width of the bottom protection can be reasonably determined.Therefore the general invalid scouring range of the spur dike head can be reduced,and the effective scouring efficiency of the spur dike on the waterway can be increased.In this way,the improvement effect of the navigation channel after the engineering is better.

关 键 词：丁坝 护底 作用效率系数 定床 动床 

分 类 号：U617[交通运输工程—船舶及航道工程]