感潮河段桥梁壅水计算方法比较及敏感性分析  

A Comparison of Bridge Modeling Approaches in One-dimensional HEC-RAS Model of Tidal Reach

作　　者：曾琼佩 王义刚[1] 黄惠明[1] 周晶晶[1] 陈橙[1] 

机构地区：[1]河海大学海岸灾害及防护教育部重点实验室,南京210098

出　　处：《长江科学院院报》2015年第7期58-63,共6页Journal of Changjiang River Scientific Research Institute

摘　　要：为体现HEC-RAS模型中感潮河段上桥梁壅水变化,建立了一维非恒定流数学模型,计算了2002年3月长江苏通大桥的壅水情况。并进一步介绍和比较了铁路工程水文勘测设计规范公式以及HEC-RAS内设的能量法、动量法、Yarnell法计算公式,对公式计算结果与HEC-RAS相关经验系数等设置进行了探讨。最后将各公式应用于3月份的苏通大桥壅水计算,结果发现:HEC-RAS的能量法和Yarnell法较符合规范法,适用于计算感潮河段的非溢流桥梁壅水;而动量法则与实际数值偏差较大,不适合该地区应用。同时比较了HEC-RAS的3种方法对扩缩系数、经验系数以及无效区域的敏感性,结果表明:扩缩系数对能量法影响最大,Yarnell法依赖于经验系数,动量法与无效区域有关,但其具体设置需要更详细的资料进行研究。研究成果可为非恒定流桥梁壅水数值模拟方法提供一些参考。An unsteady flow simulation of tidal reach based on HEC-RAS is established to calculate the backwater of Jiangsu-Nantong Bridge.Furthermore,the standard equation from Survey and Design on Hydrology ofRailway En-gineering,the energy equation,momentum balance method and Yarnell equation of HEC-RAS software are com-pared and respectively applied to the calculation.The calculated results of energy equation and Yarnell equation a-gree well with the standard equation,while the momentum balance method has a big deviation.Moreover,the sen-sitivities of HEC-RAS methods are analysed.The energy method is affected significantly by the bridge cross-section and expansion （contraction）coefficient,while Yarnell equation is dependent on the experience factor,and momen-tum method is related with the ineffective area which need more details for research.The results could be taken as reference for the unsteady flow simulation of bridge backwater.

关 键 词：HEC-RAS 感潮河段 壅水 Yarnell法 敏感性分析 

分 类 号：U442.33[建筑科学—桥梁与隧道工程]