7 - 雨水管理设计 Infiltrators (translated).pptxVIP

Design of Stormwater Controls雨水管理设计Daniel E. Medina, PhDFellowWashington DCOutline 大纲Basins集水盆地Swales and strips 草沟带Filters过滤Infiltrators渗滤设施Gross pollutant traps 污染物整体拦截Infiltrators 渗滤设施UOs in which the entire design capture volume infiltrates to the soil and percolates to shallow aquifers from which it flows to streams as interflow整个设施捕捉的雨水下渗到土壤和浅水层中，之后整股地汇入溪流。Most effective when distributed over the drainage area在整个排水区范围使用效率最好Designed using Darcy’s law for unsaturated flow使用不饱和流达西定理设计Performance depends on infiltration properties of soils渗透介质决定性能Two general types:一般有两种类型：Surface infiltrators 表面渗滤Underground infiltrators 地下渗滤蒸发蒸腾表面储水层饱和水力传导率原始土至少1.2米岩基/季节性地下水透水或普通铺面地下储水设施管道或水箱砾石层透水铺面地基饱和水力传导率岩基/季节性地下水至少1.2米Infiltrators 渗滤设施Performance depends on soil properties渗透介质决定性能Hydrologic soil groups – fine to use水力介质 – 可以使用USDA soil texture classifications – much better!USDA土壤成分分类 – 更好！(Saxton, K. E. (2009) Soil Water Characteristics: Hydraulic Properties Calculator /soilwater/Index.htm)Low temperatures reduce hydraulic conductivity低气温降低介质的水力传导率Types:类型：Infiltration basins渗滤池Infiltration trenches and vaults 渗滤沟和水窖Dry wells干井Permeable pavement 透水铺面Infiltrators-filter combination渗滤-渗透的组合Useful when soil infiltration is too fast or too slow当渗滤介质太快或太慢时，使用这样的组合Infiltration Basin 渗滤池A dry basin that captures the design volume and allows it to percolate into the ground渗滤池捕捉雨水达到设计容量后，将雨水释放到地下Surface infiltrator表面渗滤UPsVolume reduction (evapotranspiration and infiltration) 减少径流量（蒸发蒸腾和下渗）Peak flow attenuation 削峰作用Filtering过滤Sorption吸附作用Biological processes 生物过程Temperature reduction 降低温度Infiltration Basin 渗滤池Infiltration Basin 渗滤池Treats drainage areas of 2-20 ha (5-50 acres)可处理的排水范围达到2-20公顷（5-50英亩）Requires permeable soils需要使用透水介质Infiltration rates need to be field tested下渗率需要实地测试Too high of a rate may not allow adequate filtration (e.g., karst); need an upstream filter过高的下渗滤可能导致过滤的效率不足（如卡斯特地质条件）；需要设计上游过滤Design volume should infiltrate within 24-72 h设计容量应在24-72小时内下渗Pretreatment n