城市江堤外移工程对防洪影响研究  

Effects of levee realignment on flood control in urban area

作　　者：陆永军[1] 郝嘉凌[1] 李浩麟[1] 

机构地区：[1]南京水利科学研究院,江苏南京210029

出　　处：《水科学进展》2003年第2期197-202,共6页Advances in Water Science

摘　　要：以浙江省温州市瓯江江堤外移工程为例,应用二维潮流数学模型研究了堤线外移的不同工程方案对城市防洪的影响。该模型能够模拟瓯江与楠溪江交汇引起的复杂水流运动,以及多岛屿对水流流场的影响。验证计算表明,计算的潮位及18条垂线流速及断面流量过程与实测值吻合较好,误差均小于10%。因堤线外移的部分大多位于河道岸线的凹囊,适当外移可使河道岸线更趋平顺。100年一遇洪水时,瓯江大桥至鱼旗山堤线外移曲线方案1与直线方案2分别使屿头山-梅岙河段最高潮位壅高0 03～0 04m及0 04～0 08m。多年平均流量450m3/s时,方案2使塔山至鱼旗山断面垂线平均流速增加6%～22%,工程段以外河段流速变化较小;方案1缩窄的河宽和拦截过水面积明显小于方案2,相应引起流速变化也较小。As an example, the impact of the levee realignment project on the flood control of Wenzhou city is studied by a 2D tidal flow mathematical model.The verifications of the model show that the tidal levels computed by the model are in good agreement with the field data, and the tidal velocity and rate of discharge are also in accordance with the data recorded.The variance in computation versus actual results is less than 10%.Therefore, the model can be used to accurately predict the changes of tidal level, flow velocity and discharge to forecast the effects of the project.As the majority of the riverbank moved outward is in the concave area of the river, the project will create a smoother outward arc for the riverbank.It is shown from computed results that the maximum high tidal level increases 003-004 m and 004-008 m for project scheme 1 and scheme 2, respectively, in the flood frequency of 1% in the reach from the Yutoushan to the Mei′ao.With an annual mean discharge of 450 m3/s, the vertical average velocity in the reach from the Tashan section to Yuqishan section increases 6% to 22% after the completion of project scheme 2The change in velocity in the reach outside of the project is small.The impact of the project on the bifurcation ratio of the Jiangxinsi branch is very small.The river blocked by project scheme 1 is much smaller than that by project scheme 2, and the change in velocity created by project scheme 1 is also smaller than that by project scheme 2The results computed by the model can be used as a reference for decision making.

关 键 词：城市江堤 防洪工程 多连通域 贴体坐标 数学模型 

分 类 号：TV871[水利工程—水利水电工程]