【作者】 武晟；

【导师】 汪志荣； 张建丰；

【作者基本信息】 西安理工大学 ， 环境工程， 2004， 硕士

【摘要】 本文结合国家自然科学基金项目和陕西省水资源与环境重点实验室建设项目，在阅读并综述了大量国内外相关文献基础上，根据西安市马渡王水文站的21年(1980年-2000年)降雨时、日资料，分析了西安市降雨特性。同时，为研究城市下垫面的产汇流特性研制了一套人工模拟降雨系统，并对相关评价指标进行了实测校验。在此基础上，进行了200多场降雨实验，分析了雨强、历时、土壤前期含水量、温度、降雨量、不同下垫面和不同覆盖度等对产汇流的影响，及各种因素对径流系数的影响和相关性，建立了一定条件下历时～径流系数，雨强～径流系数，流量～径流系数的函数模型。最后，在对降雨特性、下垫面产汇流特性分析的基础上，以西安理工大学金花校区和陕西省水资源与环境重点实验室屋顶为典型小区，简单的计算分析了西安市文化区和屋顶下垫面的降雨径流量。从量的角度分析了雨水利用前景。 本文根据降雨资料分析、设备研制、实验研究和数学分析以及实例的计算，主要得到了以下成果和结论。 1．西安城区多年平均降雨量为623.96mm，降雨主要集中在6～10月，一年当中日降雨多为10mm／d以下。从利用地表径流的角度出发，提出了次降雨的划分标准，即按照城区下垫面的下渗能力恢复时间来作为划分次降雨的依据。统计出了21年1313次降雨资料。采用皮尔逊Ⅲ型曲线方法，设计出了西安城区1h、2h、3h、4h、5h、6h这6个时段的暴雨雨强～频率～历时关系曲线，并设计了历时12h的1年1遇暴雨雨型。 2．设计并研制了城市下垫面降雨产汇流实验系统。在降雨器设计中，传统的降雨均匀度计算公式并不能衡量降雨强度空间分布的均匀性，本文提出了检验雨强空间分布均匀程度的校验参数及检验空间均匀度优劣的计算方法，给出了校验该参数应达到的最小值。在实验设备校验中，该参数也作为了一个校验指标，并通过了校核。西安理工大学硕士学位论文 3.根据喷头特性和均匀度等要求，编制了喷头、供水支管布置优化设计的程序，并利用软件之间的兼容性，使优化结果可视化;测控系统中的翻斗特性实验证明，采用实测流量一翻转历时来计算翻斗水量，大大降低了测量和计算误差，误差必.01，并且提高了实验效率。 4.对于透水性差的下垫面，雨强越大，流量过程的涨水曲线越陡，且达到稳定流量的速度也更快，但对流量过程的退水历时影响不大。在同雨强时，涨水速度从大到小依次为:水泥路面、SBS、不透水砖。而达到稳定流量的历时则正好相反。 5.雨强相同时(l .Omm/min)，入渗能力和地表平整程度是影响透水性下垫面(透水地砖和草地)涨水曲线的主要因素。涨水过程中，覆盖度增加，涨水过程逐渐变缓，以覆盖度为0%和透水砖为最陡和最缓过程，且达到稳定流量的时间加长，稳定流量减小，而透水砖达到稳定流量的时间儿乎和100%覆盖度的草地相当。值得注意的是覆盖度>80%后，涨水曲线缓势明显。降雨条件相同情况下，与草地相比，透水砖的退水历时短。草地覆盖度逐渐增加(0%一100%)，退水历时呈现逐渐增大再逐渐减小的过程，80%覆盖度时退水历时达到最大。 6.对历时一径流系数关系、雨强一径流系数关系、流量一径流关系做拟合，双曲线型拟合效果最好。透水性差的三种下垫面在历时增量相同条件下或在相同的雨强增量条件下，径流系数增加由少到多依次为:水泥路面、不透水砖、SBS。透水性好的两种下垫面由于下渗能力强，减弱了雨强、历时对径流系数的影响，拟合曲线的相关性稍逊于透水性差的下垫面 7.对于草地，相同历时、雨强、土壤前期含水量条件下，覆盖度越低，径流系数越大，特别在80%左右的覆盖度时，成为径流系数变化快慢的转折点。影响草地径流系数变化的因素从强到弱依次为:土壤前期含水量、降雨强度、降雨历时。气温和覆盖度与径流系数成负相关。对于透水砖，影响径流系数变化的因素从强到弱依次为:雨强、土壤前期含水量、‘历时。 8.以金花校区复合下垫面和陕西省水资源与环境重点实验室屋面材料为实例，分析计算了多年平均降雨径流量。结果表明，计算区的下垫面的产汇流能力较强，年降雨量的70%都形成了地表径流。采用屋顶进行雨水收集回用，其径流量甚至超过了该办公楼的年用水量，如果加以适当的回收利用，将是一个既能充分利用淡水资源，又能获得经济效益的好方法。更多还原

【Abstract】 Connecting with country’s natural scientific fund item and water resources and environmental important experiment item of Shann’xi province, on the basis of large sum of reading about domestic and overseas relative literatures, according to the rainfall data, including per day and per hour rainfall data of 21 years (from 1980 to 2000), the paper analyzed the rainfall characters. Meanwhile, an artificial imitation rainfall system was developed in order to study the characteristics of city underlying surface and make experimental check up about the relative appraising index, on which 200 rainfall experiments are made, analyzing the effect of rainfall intensity to the runoff of underlying surface; the relationship between runoff permeability and unit factor of rainfall intensity and duration; The effect of rainfall intensity, duration, soil moisture content, and temperature to the runoff permeability; The relationship between rainfall quantity and runoff permeability, and make mathematical imitation to the experimental results, to find the mutual-relationships, and make discussion about the differences between equations of fit. At last, on the basis of analyzing the characteristics of rainfall and runoff-producing and flow concentration and taking the example of multiple -underlying surface of Jing Hua School Area and stressed laboratory building materials of hydrology and environment of Shann’xi, and thus rainfall runoff amount in the cultural areas and roof underlying surface are calculated, and utilizing foreground of rainfall are analyzed.According to the rainfall data analysis, equipment development, experimentation investigation, mathematical analysis and the calculation of examples, from which the product and conclusion are made as follow.1. The rainfall amount of Xi’an is 623.96mm on average for many years. Which is often happened in June to October and the rainfall amount per day of the year is below 10mm/d. From the point of view of utilizing surface runoff, the secondary rainfall standard is projected, that is taking the capability of infiltration recovery time of underlying surfaceas the basis of rainfall. Record the falling data of 1313 times during 21 years. Rainfall intensity, frequency, and duration relationship curve of rainstorm was developed in the six period of the city zone in Xi’an, i.e. lh,2h,3h,4h,5h,6h respectively, by adopting the curve method of Pearson type 3 curve, and the rainstorm type which occur only once a year in 12h was developed.2. Design and development of the experimental system of runoff-producing and flow concentration of city underlying surface. In the process of devising rainfall apparatus, the calculative formula of traditional rainfall degree of consistency can’t weight the uniformity of rainfall space. The paper suggests the checkup parameter and calculative method used in testing the degree of consistency of the rainfall intensity in rainfall space. Providing the least value of test which as a testing index in the testing of experimental apparatus.3. Based on the requirements of the character of jet nozzle and degree of consistency, jet nozzle and optimized design procedure of water supply branch distribution were devised. And utilized the compatibility of software saw the optimized products. In order to advance the precision of data processing, practical quantity of flow and turnover duration were adopt to calculate the quantity of water of tilting bucket The experiment of character of tipping bucket in the measure and control system shows that the error between the measurement and calculation, (<=0.01) decreased sharply, and the efficiency is promoted greatly.4. As for the three kinds of waterproof underlying surface, when rainfall intensity is strong, the rise process curve will steep in the process of discharge, and also speed of discharge to reach steady will quicker. But it produces little effects on duration of fall. On the same rainfall intensity, speed rate of these three kinds of underlying surface are list as: cement road surfac更多还原