不同降雨条件下低冲击开发的水文效应分析

Hydrological Effect Analysis of Low Impact Development under Different Rainfall Conditions

以深圳市光明新区低冲击开发(LID)示范区为研究区域,采用暴雨雨水管理模型(SWMM)模拟了下凹式绿地、渗透铺装和绿色屋顶等3种LID模式下的雨洪控制效果,分析了降雨量、降雨历时和雨峰位置对LID水文效应的影响。结果表明,当降雨量<100 mm时,随着降雨量的增加,渗透铺装和绿色屋顶的径流削减量也相应增加,下凹式绿地的径流削减量变化不大,但其削减量大于其他两种LID控制措施;随着降雨历时的延长,下凹式绿地的径流削减量增加,而渗透铺装和绿色屋顶的径流削减量变化较小;雨峰位置变化时,3种LID控制措施的径流削减量均变化不大,对峰值流量的削减效果随着雨峰后移而减弱。3种LID控制措施对降雨量少、降雨历时长并且雨峰位置靠前的降雨控制效果较好。

Hydrological Effect Analysis of Low Impact Development under Different Rainfall Conditions LI Zhuo-xiI, QIN Hua-peng1 , XIE Kun2 （ 1. Key Laboratory for Environmental and Urban Sciences, School of Environment and Energy, Shenzhen Graduate School, Peking University, Shenzhen 518055, China; 2. Meteorological Bureau of Shenzhen Municipality, Shenzhen 518040, China） Abstract： The stormwater management model （SWMM） was used to simulate the stormwater con- trol effect in a low impact development （LID） demonstration area in Guangming New District, with three different LID practices--sunken lawn, pervious pavement and green roof. The influences of different pre- cipitations, rainfall durations and moments of rainfall peak occurrence on the hydrological effect of LID were analyzed. The results showed that when the precipitation was lower than 100 ram, pervious pave- ment and green roof reduced more runoff as precipitation increased, and the reduction of runoff by sunken lawn did not change much, but sunken lawn reduced runoff more than the others. Sunken lawn reduced more runoff as rainfall duration increased, but the reductions of runoff by pervious pavement and green roof did not change much. When the moments of rainfall peak occurrence were different, the reductions of runoff by three LID practices were similar, while they reduced less peak flow as the moment of rainfall peak occurrence was later. The three LID practices could effectively control the rainfall with less precipitation, longer rainfall precipitation and earlier moment of rainfall peak occurrence.