城市地表径流内涝关系与排洪道优化设计研究——以兰州市为例  

Research on the Relationship between Urban Surface Runoff and Waterlogging and the Optimization Design of Spillway:A Case Study of Lanzhou

作　　者：陈金林[1] 李鑫[1] 余建平[1] 李计生 CHEN Jinlin;LI Xin;YU Jianping;LI Jisheng(College of Petroleum and Chemical Engineering,Lanzhou University of Technology,Lanzhou 730050,China;Gansu Provincial Hydrological Station,Lanzhou 730050,China)

机构地区：[1]兰州理工大学石油化工学院,甘肃兰州730050 [2]甘肃省水文站,甘肃兰州730050

出　　处：《灾害学》2024年第2期6-11,20,共7页Journal of Catastrophology

基　　金：甘肃省水利厅“石羊河流域水文循环及四水转化实验研究”(22GSLK057)。

摘　　要：为探究暴雨后地表径流与城市内涝关系,以兰州市为例,利用ArcGIS软件对其数字高程模型进行水文分析,获得了兰州市地表径流空间分布。根据地表径流空间分布规律,从城市全局视角分析了兰州市城市内涝问题,并对兰州市现有排洪道进行了优化。结果表明:易涝路段与径流路径具有高度相关性,地表径流流经大部分内涝路段,导致内涝发生,且径流路径的密集程度与内涝的严重程度相关,其中城关区最为严重,七里河区与西固区次之,安宁区相对轻微,符合兰州市现实情况,说明了该模型方法的正确性;内涝点集中分布在建筑用地、裸地(水泥地面等)区域,表明城市下垫面的高不透水率是造成道路积水的原因之一;优化后的排洪道使易涝区域的雨水就近排入洪道,减少了薄弱地区洪水冲入城市街道的可能性,减轻了地下排水设施的排水压力,在一定程度上能够解决城市内涝问题;将山地原始沟渠巩固、加宽、延长为新建排洪道,减少了发生山洪的风险。因该研究区域黄河穿城而过,地表径流最终通过排洪道汇入黄河,故该方法可为我国后续整个黄河流域、长江流域“一河一盘棋”的整体防洪研究提供参考。In order to explore the relationship between surface runoff and urban waterlogging after a heavy rain in Lanzhou,a hydrologic analysis on the digital elevation model is done by ArcGIS,and the space distribution of the surface runoff in Lanzhou is extracted.Then the urban waterlogging problem of the city is analyzed from a city global perspective,and the existing spillway in Lanzhou is optimized.The results show that there is a high correlation between waterlogging-prone sections and runoff paths,surface runoff flowing through most waterlogged sections leading to waterlogging.The density of runoff paths is related to the severity of waterlogging.Chengguan district has the most severe flooding,followed by Qilihe and Xigu districts,and Anning district is relatively light.Those are consistent with the actual situation in Lanzhou.The correctness of the model is thus demonstrated.The concentrated distribution of waterlogging points are on construction land and bare land(such as cement floors),which indicates that the high impermeability of urban underlying surfaces is one of the reasons for road waterlogging.The optimal design of spillway,discharging rainwater in waterlogged areas into spillway nearby,reduces the possibility of flood rushing into urban streets in weak areas,and the drainage pressure of underground drainage facilities.The optimal design of spillway can solve the problem of urban waterlogging to some extent.In addition,consolidating,widening,and extending the original mountain ditches into new flood discharge channels has reduced the risk of flash floods.Due to the fact that the Yellow River passes through the city in this study area,surface runoff ultimately flows into the Yellow River through a spillway.Therefore,this method can provide a reference for the overall flood control research of the entire Yellow River basin and the Yangtze River basin in China's future"One River,One Game"study.

关 键 词：城市内涝 ArcGIS 地表径流 排洪道 一河一盘棋 甘肃兰州 

分 类 号：X43[环境科学与工程—灾害防治] X915.5