河道斜交桥梁壅水及流场特性分析  

Analysis of backwater and flow field characteristics of skew bridge in river channel

作　　者：石喜[1] 谭春彬 贡力[1] 陶虎[1] SHI Xi;TAN Chun-bin;GONG Li;TAO Hu(School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]兰州交通大学土木工程学院,甘肃兰州730070

出　　处：《泥沙研究》2024年第2期64-71,共8页Journal of Sediment Research

基　　金：国家自然科学基金项目(51969011);甘肃省自然科学基金项目(20JR10RA239);甘肃省高等学校产业支撑计划项目(2022CYZC-32)。

摘　　要：圆端桥墩是平原河道内一种常见的桥墩型式,为探究斜交圆端桥墩不同布置方式引起的壅水特性和水流流态变化,建立三维数值模型,采用SIMPLE算法耦合k-ε紊流模型求解N-S方程组,应用VOF法追踪自由液面,分析了单个桥墩壅水特性、绕流流场和升阻力系数随斜交角度变化的规律。研究结果表明:下游墩前壅水高度最大,壅水长度最长,上游墩前冲高值最大;水流绕流经过上游桥墩后偏向下游桥墩侧,桥墩垂直桥轴线布置方式绕流形成的壅水叠加效应更明显;斜交桥梁布置采取圆端桥墩时,桥墩顺水流布置,可有效减小阻水宽度与壅水高度,弱化流场结构变化。Round-end pier is a common type of bridge pier in plain rivers.In order to investigate the changes of backwater characteristics and flow patterns caused by different arrangements of obliquely intersecting round-end piers,a three-dimensional flume numerical model is established,the SIMPLE algorithm coupled with k-8 turbulent flow model is used to solve the N-S equation system,the VOF method is applied to trace the free liq-uid surface,and the changes of backwater characteristics,bypass flow field and lift-resistance coefficients of a single pier with the angle of obliquity are analyzed.The results show that:the effect of backwater in front of the downstream pier is the largest in height and the longest in length,and the impulse height in front of the up-stream pier is the largest.The current flows around the upstream pier and deviates to the downstream pier side,the larger the angle of oblique crossing,the backwater superposition effect formed by the bypassing flow is more obvious.The round-end piers are suggested to be arranged along the water flow when building an ob-lique crossing bridge,which can effectively reduce the water blocking width,backwater height and the impact on flow field.

关 键 词：斜交桥 数值模拟 圆端桥墩 布置方式 壅水 流场 

分 类 号：U442.3[建筑科学—桥梁与隧道工程]