高地下水位地区透水停车场的水文控制效果

Hydrological Performance Assessment of Permeable Parking Lots in High Water Areas

为确定高地下水位地区透水铺装对路面径流的水文控制效果,在上海市区建造了4个实验性透水铺装单元与1个不透水铺装对照,其中3个为设有防水衬底的不透型设施分别为透水混凝土铺装(设施Ⅰ)、水泥稳定碎石基层/缝隙透水砖面层(设施Ⅱ)、碎石基层/缝隙透水砖面层(设施Ⅲ),1个普通缝隙透水砖铺装(设施Ⅳ),以及1个不透水混凝土对照(设施0).历时1年监测了实际降雨条件下4种实验设施的表面径流、排水管出流流量及表面渗透速率,考察不同设施的径流总量削减率、峰值削减及峰现延迟能力.结果表明,缝隙透水砖面层的表面稳定渗透速率明显小于透水混凝土面层,使用1年后,2种面层表面稳定渗透速率均明显下降;4种设施的表面产流均无显著差异;3种不透型设施的就地消纳水量能力均较弱,年径流总量控制率分别为24.2%、28.5%、28.4%,排水管不发生出流的控制降雨量分别为5.2 mm、7.8 mm、7.8 mm;设施Ⅰ的峰值削减与峰现延迟效果弱于设施Ⅱ及设施Ⅲ,且3种设施的峰值削减率和峰现延迟时间与降雨强度呈现显著负相关性.

In order to evaluate the hydrological performance of permeable pavements in mitigating the surface runoff,four pilot-scale permeable pavement units were constructed in Shanghai and compared with impervious pavements. Three of the permeable facilities with waterproof liners included a pervious concrete pavement（ facility Ⅰ）,permeable interlocking concrete pavement using cement stabilized macadam as the base course（ facility Ⅱ） and permeable interlocking concrete pavement using macadam as the base course（ facility Ⅲ）. The other two facilities were a conventional permeable interlocking concrete pavement without a liner（ facility Ⅳ） and an impervious concrete pavement control（ facility 0）. V-notch flow meters,data loggers,and a rainfall meter were mounted to monitor the hydrological data. A double-ring infiltrometer was applied to evaluate the infiltration rate of the pavements. During the one-year experiment,the surface runoff and the underdrain discharge flow rate of the four pilot-scale facilities were continuously monitored in actual rainfall and the total volume reduction,peak flow reduction,and peak concentrating time of different facilities were investigated.The results showed that the surface steady infiltration rates of permeable interlocking concrete pavements were less than those of the pervious concrete,and the surface steady infiltration rates of the two types of surface layers decreased after one year of usage. The surface runoff reduction of the four facilities showed no significant differences. The water volume reduction rate of the three types of facilities was weak. The annual total volume reduction rates were 24. 2%,28. 5%,and 28. 4%,and the controlled rainfall amounts were 5. 2 mm,7. 8 mm,and 7. 8 mm. The peak flow reduction rate and the time to the peak flow of facility Ⅰ were smaller than those of facility Ⅱ and facility Ⅲ. The peak flow reduction rate and the time to the peak flow of the three facilities showed significant negative correlation with rainfall intensity.