摘要
为了解桥墩形状引起的壅水特性,建立三维水槽模型,使用水工模型试验数据对数值模型进行对比验证,探讨圆形、圆端形、矩形桥墩在不同斜交角度和阻水比时壅水及桥墩周边流场变化规律。结果表明,阻水比越大,桥前壅水曲线长度越大且墩后跌水现象越显著;壅水值随斜交角的增大先变大后减小,随阻水比的增加而增大;阻水比小于9%时圆形壅水值最大,在大于9%时矩形壅水值最大,圆端形壅水值最小;斜交角度小于30°时圆形壅水值最大,圆端形墩最小,大于30°时矩形壅水值最大,圆端形最小;随斜交角度增加,流速分布发生非对称性改变,大流速分布范围不断向下游侧河岸偏移;流向偏转角随斜交角度增加先增大后减小且与阻水比呈正相关,矩形墩对水流流态干扰最大。研究结果可在一定程度上为桥梁防洪设计提供参考。
In order to understand the backwater characteristics caused by the shape of the bridge pier,a three-dimensional flume model was established,and the numerical model was compared and verified by the hydraulic model test data.The variation law of backwater and flow field around piers of circular,round-ended and rectangular piers at different skew angles and water resistance ratios was discussed.The results show that the larger the water blocking ratio,the longer the backwater curve in front of the bridge and the more significant the phenomenon of water drop behind the pier;The backwater value increases first and then decreases with the increase of oblique angle and increases with the increase of water resistance ratio;When the water blocking ratio is less than 9%,the circular backwater value is the largest;When it is greater than 9%,the rectangular backwater value is the largest,and the round end backwater value is the smallest;When the oblique angle is less than 30°,the circular backwater value is the largest and the round-ended pier is the smallest;When the oblique angle is greater than 30°,the rectangular backwater value is the largest and the round-ended pier is the smallest;With the increase of oblique angle,the flow velocity distribution changes asymmetrically,and the distribution range of large flow velocity continues to shift to the downstream bank;The flow direction deflection angle increases first and then decreases with the increase of the oblique angle and is positively correlated with the water resistance ratio;The rectangular pier has the greatest interference with the flow direction.The research results can provide reference for bridge flood control design to a certain extent.
作者
王勇
季日臣
王国汇
方晟浩
WANG Yong;JI Ri-chen;WANG Guo-hui;FANG Sheng-hao(School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;Institute of Computing Technology,China Academy of Railway Sciences Group Co.,Ltd.,Beijing 100081,China)
出处
《水电能源科学》
北大核心
2025年第5期80-83,20,共5页
Water Resources and Power
关键词
斜交桥
数值模拟
桥墩形状
壅水
偏转角
skew bridge
numerical simulation
bridge piers types
backwater
deflection angle
