新型渗井-透水网格措施的径流调控效果研究

为更加合理地对雨水资源进行管理和调控,低影响开发(LID)措施日益成为我国许多城市"海绵化"的必然选择。透水网格被认为是一种有着良好雨洪管控效用的LID措施,然而大多情况下施工过程不尽规范,土基多采用渗透性不良的土质,这使得径流调控及渗流效益难以充分发挥,故拟以透水网格砖孔布设渗井来改善该现状。采用试验与SWMM仿真相结合的方法,研究了在6场重现期降雨作用下新型渗井-透水网格措施较透水网格在径流调控方面的改善效果,以及100年重现期降雨条件下两种措施的入渗规律。结果表明,在不同降雨场次下,新型措施较透水网格雨量径流系数降低了9. 94%～51. 09%,洪峰流量削减率提高了2. 91%～30. 42%;滞峰时间延迟效果不显著,在3 min以内;在100年重现期降雨下湿润锋迁移速率提高了73. 47%。

Runoff Regulation Effect of New Type Seepage Well and Permeable Grid Measures

In order to manage and control rainwater resources more reasonably,the low impact development (LID) has increasingly become an inevitable choice for sponge city construction of many cities in China. Permeable grid is considered to be a low impact development measure with good stormwater management effect. However,most of permeable grid is not standardized,and the soil foundation is mostly made of poorly permeable soil,which makes it difficult to fully utilize runoff regulation and seepage benefits. Therefore,seepage wells were planned to be laid in the permeable grid pavement brick hole to improve the present situation. Using the method of experiment and SWMM simulation,the improvement effect of new type seepage well and permeable grid measures on runoff regulation under six rainfall events with different return periods were investigated,and the infiltration law of the two measures under the rainfall of 100-year return period was explored. The runoff coefficient of the new measures was 9. 94%-51. 09% lower than that of the permeable grid under different rainfall events,sand the reduction rate of peak flow increased by 2. 91%-30. 42%. The delayed effect of peak lag time was insignificant,which was less than 3 minutes,and the migration rate of wet front increased by 73. 47% under the rainfall of 100-year return period.