低影响开发模式下住宅小区年径流总量控制率研究

选取北京市海淀区某雨水利用小区为研究对象,构建SWMM模型。对透水铺装和蓄水池2种低影响开发措施运行模式下的水量控制进行评价。首先,通过研究区实测降雨产流数据进行模型的率定和验证,得到可用的SWMM模型;分别对1年一遇、3年一遇、5年一遇、10年一遇和20年一遇24 h降雨雨型进行模拟,计算研究区实际年径流总量控制率;并计算研究区开发前的控制率。通过改变研究区现状硬化路面透水铺装率和调蓄容积计算年径流总量控制率,对研究区两项措施规模的配比进行分析计算。结果表明,以透水铺装和蓄水池两种组合方式改造的居住小区年径流总量控制率大大提高,小区改造后比改造前年径流总量控制率提高了42%;对不同规模硬化路面透水铺装和蓄水池进行计算可知,透水铺装和蓄水容积对控制率均有影响。当硬化路面透水铺装率达到70%,蓄水池容积改变率达到30%时,研究区年径流总量控制率达到85%的要求。研究成果能够应用于缺少实测数据的城市集雨区域,可对不同LID组合方式的径流减控效果研究提供参考。

Study on volume capture ratio of annual rainfall of residential area in Low Impact Development mode

Taking a rainwater utilization residential area in Haidian District of Beijing as the object of study and building a SWMM model as research method, this paper evaluates water control in 2 operation modes of low impact development measures: permeable pavement and storage tank. Firstly, get the available model after calibration and validation by measured rainfall-runoff data in the study area. Secondly, simulate 1-year, 3-year, 5-year, 10-year, 20-year 24h rainfall, then calculate actual volume capture ratio of annual rainfall and the rate before development in the study area. Finally, change proportion of permeable paving and storage volume and calculate volume capture ratio of annual rainfall, then calculate and analyse the proportion of scale of the two measures. The results indicate that volume capture ratio of annual rainfall in residential area rises greatly after reconstruction of permeable pavement and reservoir. Take this research as an example, volume capture ratio of annual rainfall increased by 42% compared with the ratio before reconstruction. The calculation of permeable pavement and reservoir on different scale shows that both the permeable pavement and storage volume have influence on the control rate. When proportion of permeable paving reaches 70% and the variation rate of reservoir volume reaches 30%, volume capture ratio of annual rainfall in the study area can meet requirement of 85%.The research result can be applied to urban catchment areas short of the measured data,and it also provide reference for the researches about runoff control effect of different LID measures combinations.