雨水花园径流系数的率定及影响因素分析

发布时间：2018-05-28 08:49

本文选题：雨水花园 + 径流系数　；参考：《西南交通大学》2017年硕士论文

【摘要】：城市化进程的加快伴随城镇道路的建设,使得原有的地形地貌和土壤结构发生变化,不透水路面增加。同时随着极端天气的频繁发生,降雨历时短、降雨强度大的局部突发性暴雨频繁发生,严重造成城市内涝[1,2]。设计滞后是造成城市内涝的主要原因,而径流系数是估算降雨净流量的基础资料,也是进行雨水设计流量计算的重要参数[3]。现在雨水管网设计中径流系数的取值,主要参考《室外排水设计规范》(GB50014-2006)和《建筑给排水设计规范》(GB50015-2003)中的规定[4],而设计规范规定的径流系数是按地面覆盖种类确定的经验数值,并没有从工程实际角度出发,把降雨历时、降雨强度、地貌等因素考虑进去。本课题以成都市新津县雨水花园试验基地为研究对象,将修建了雨水花园的2#路和未建雨水花园的18#路作对比研究,收集试验区域和试验期间的降雨资料,分析试验期间的降雨类型、降雨量、降雨历时以及降雨强度等,采用水量平衡原理和等流时线法对整个降雨-产流-汇流过程进行分析,结合两条道路监测的出流流量进行最优拟合,率定试验区域的径流系数,分析其影响因素,为实际工程建设中排水管网的设计提供设计参数,为城市内涝控制理论研究、实际工程设计应用提供理论参考。课题研究成果显示,试验期间采集的降雨数据覆盖多种雨型,存在不同的降雨强度、降雨历时,试验区域涉及四种不同的下垫面,主要为沥青车行路面、人行道、绿化隔离带、原始坡地。以上因素均对试验区域的径流系数产生影响。通过9月5日这天的降雨量和出流量率定得到的2#路和18#道路的径流系数可知,建有雨水花园的2#路的径流系数远小于18#路的径流系数,说明建有雨水花园的道路相对于未建雨水花园的道路具有更好的雨洪调控作用,对控制城市内涝有积极意义;同时对有效降雨期间率定得到的径流系数值分析可知,不同的下垫面径流系数不同,在试验区域表现为沥青道路径流系数、人行道路面径流系数绿地、坡地路面径流系数的总体趋势,绿地和坡地对降雨有较强的滞留作用;同样的下垫面,径流系数受到降雨量、降雨历时和降雨强度等因素的影响,径流系数和降雨历时和降雨强度呈正相关关系,随降雨历时的延长而增大,随降雨强度的增大而增大。研究率定得到的径流系数与设计规范中的径流系数取值相比有一定的差异,这说明实际的地域环境径流系数受影响因素复杂,波动较大,在进行工程设计时需要因地制宜,综合考虑[4]。
[Abstract]:Along with the construction of urban roads, the acceleration of urbanization makes the original landform and soil structure change, and the impermeable pavement increases. At the same time, with the frequent occurrence of extreme weather, the rainfall duration is short, and the local sudden rainstorm with large rainfall intensity occurs frequently, causing serious urban waterlogging. The design lag is the main cause of urban waterlogging, and the runoff coefficient is the basic data for estimating the rainfall net flow, and is also an important parameter for the calculation of the Rain Water design flow [3]. At present, the value of runoff coefficient in the design of rainwater pipe network is mainly referred to the provisions in "Outdoor drainage Design Code" (GB50014-2006) and "Building Water supply and drainage Design Code" (GB50015-2003) [4], while the runoff coefficient specified in the design code is the empirical value determined according to the type of ground cover. The factors of rainfall duration, rainfall intensity, geomorphology and so on are not taken into account from the point of view of engineering practice. Taking the Rain Water Garden Experimental Base in Xinjin County of Chengdu as the research object, the paper makes a comparative study of the Rain Water Garden's 2# Road and the 18 # Road without the Rain Water Garden, and collects the rainfall data of the experimental area and the trial period. The rainfall types, rainfall, rainfall duration and rainfall intensity during the experiment are analyzed. The whole process of rainfall, runoff generation and runoff concentration is analyzed by using the principle of water balance and the isochron method. Combined with the optimal fitting of the discharge of the two roads, the runoff coefficient of the test area is determined, and the influencing factors are analyzed, which can provide design parameters for the design of the drainage pipe network in practical engineering construction, and provide theoretical research for the control of urban waterlogging. The practical engineering design application provides the theory reference. The research results show that the rainfall data collected during the test period cover a variety of rain patterns, and there are different rainfall intensity and duration. The test area involves four different underlying surfaces, mainly asphalt vehicle pavement, sidewalk, and green separation zone. The original slope. All the above factors have an effect on the runoff coefficient of the test area. Based on the runoff coefficients obtained from the rainfall and discharge rate of September 5, the runoff coefficients of the road with Rain Water garden are much smaller than those of the road 18#, and the runoff coefficient of the road 18 # is far less than that of the road 18 #. It shows that the road with Rain Water garden has better rain and flood control function than the road without Rain Water garden, and has positive significance in controlling urban waterlogging, meanwhile, the analysis of runoff coefficient value obtained from the rate of effective rainfall period shows that, The runoff coefficient of different underlying surface is different. In the test area, the runoff coefficient of asphalt road, pavement, the general trend of runoff coefficient of sloping land and the effect of green land and slope land on rainfall retention are shown. In the same underlying surface, the runoff coefficient is affected by rainfall, rainfall duration and rainfall intensity, and the runoff coefficient is positively correlated with rainfall intensity, and increases with the increase of rainfall duration. It increases with the increase of rainfall intensity. The runoff coefficient determined by the research rate is different from the runoff coefficient value in the design code, which indicates that the actual regional environmental runoff coefficient is affected by complex factors and fluctuates greatly, so it is necessary to take measures according to the local conditions in the engineering design. Comprehensive consideration [4].
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P333.1

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