SWMM在排水防涝规划中的应用研究

发布时间：2018-07-05 12:05

本文选题：排水防涝 + SWMM　；参考：《湖南大学》2014年硕士论文

【摘要】：近年来，，受全球气候变化影响，很多城市出现了严重的暴雨内涝灾害，严重危害了社会管理、城市运行和居民的日常生活。针对上述情况，住房和城乡建设部印发了“城市排水（雨水）防涝综合规划编制大纲”，根据大纲要求，县城中心城区应能有效应对不低于20年一遇的暴雨，并且对于集雨面积超过2平方公里的管段，推荐使用水力模型对雨水管渠的规划方案进行校核。本研究使用美国环保局开发的SWMM（暴雨雨水管理模型）软件作为主要研究工具，以宁乡县城为例：（1）以芝加哥降雨过程线法设计2年一遇降雨，对宁乡县城现状管渠进行雨洪模拟，模拟结果与现状资料溢水处基本吻合，验证了SWMM模拟的合理性；采用长沙市最新暴雨强度公式对宁乡县现状溪渠重新设计，以2年一遇的重现期确定管渠尺寸。（2）用SWMM对重现期为2年降雨下的规划雨水系统进行校核，模拟结果表明，取P=2a时，除DY4-4节点出现少量溢水，推理公式法所设计的雨水系统基本满足两年一遇降雨的排水要求，验证了SMMM模拟的合理性。（3）再次使用芝加哥降雨过程线法设计20年一遇的降雨，用SWMM模型对上述推理公式法确定的雨水管渠进行模拟，当管渠水位线超过地面高程线，即发生溢流，形成地面积水；通过增设雨水调蓄池模拟20年一遇降雨下管渠的水流状态；以没有地面溢流为原则确定雨水调蓄池的容积，使得规划雨水管渠的排水能力能够满足20年一遇的降雨要求。（4）城市化进程严重破坏了城市下垫面的透水性，直接导致雨水径流、洪峰流量的大大增加。事实证明仅仅提高排水管渠设计暴雨重现期标准是远远不够的，不但工程造价很高，而且限于场地条件，很难在城市的老城区对现有管网进行改造。我们可以采用贴近自然的雨水管理办法，尽可能不立即将城市雨水排入管道和河流中，而是利用城市现有洼地水体进行分散的蓄留和初步净化，将雨水短暂地存储起来，再缓慢排入河流。（5）根据宁乡县城区的实际地势情况，利用闲置空地改造成调蓄池。在20年一遇的设计降雨下，较大的雨水径流量在经过调蓄池后出流流量明显减小，从而起到了防涝的作用。利用洼地蓄水或修建调蓄池能够减少排水系统中排水管渠的尺寸和造价，是一项能有效提高城市现有排水系统排水防涝能力的工程措施。
[Abstract]:In recent years, under the influence of global climate change, many cities have suffered severe rainstorm and waterlogging disaster, which has seriously damaged the social management, urban operation and daily life of residents. In response to the above situation, the Ministry of Housing and Urban-Rural Construction issued an outline for the Comprehensive Urban drainage (Rain Water) Flood Prevention Plan. According to the outline, the central city of a county should be able to cope effectively with rainstorms of not less than 20 years. It is recommended that the hydraulic model be used to check the planning scheme of the rainwater pipe canal for the section of rainwater catchment area exceeding 2 square kilometers. In this study, the US Environmental Protection Agency (EPA) developed SWMM (rainstorm Rain Water Management Model) software as the main research tool, taking Ningxiang County as an example: (1) the Chicago rainfall process line method is used to design the rainfall once in 2 years. The simulation results of rain and flood in the current pipe and canal of Ningxiang county are in good agreement with the overflow of the current data, which verifies the rationality of SWMM simulation, and redesigns the current river canal in Ningxiang county by using the latest rainstorm intensity formula in Changsha. The size of pipe and canal is determined by the recurrence period of 2 years. (2) the planning Rain Water system with 2-year rainfall is checked. The simulation results show that a small amount of overflow occurs except for the DY4-4 node at 2a. The Rain Water system designed by the reasoning formula method basically meets the drainage requirement of rainfall once in two years, which verifies the rationality of the simulation. (3) the rainfall once in 20 years is designed by using the Chicago rainfall process line method again. SWMM model is used to simulate the stormwater pipe canal determined by the above reasoning formula method. When the water level of the pipe canal exceeds the ground elevation line, there will be overflow, and the surface water will be formed, and the flow state of the pipe canal will be simulated by adding Rain Water storage tank to simulate the flow state of the pipe canal under 20 years of rainfall. Based on the principle of no surface overflow, the volume of the Rain Water storage tank is determined, which makes the drainage capacity of the rainwater pipe can meet the rainfall requirement once in 20 years. (4) the urbanization process has seriously damaged the permeability of the urban underlying surface. Rain Water runoff and Hong Feng flow increase greatly. It has been proved that it is far from enough to raise the standard of rainstorm recurrence period of drainage canal design only. Not only the engineering cost is very high, but also the site condition is limited, it is very difficult to transform the existing pipe network in the old urban area of the city. We can use the Rain Water management method, which is close to nature, to not immediately drain the city Rain Water into pipes and rivers, but to use the city's existing depressions for scattered storage and initial purification to store Rain Water for a short period of time. (5) according to the actual terrain of Ningxiang County, the idle space is transformed into a storage pond. Under the design rainfall once in 20 years, the larger Rain Water runoff decreases obviously after passing through the storage tank, which plays the role of waterlogging prevention. Using depressions to store water or build storage tanks can reduce the size and cost of drains in the drainage system. It is an engineering measure that can effectively improve the drainage and waterlogging prevention capacity of the existing drainage systems in cities.
【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU992.01

【参考文献】