复合基质层对生物滞留池渗透性能的影响探究

Exploration on the Effect of Composite Matrix Layer on Permeability of Biological Detention Tank

渗透性能是影响海绵城市低影响开发设施生物滞留系统去污能力的重要因素之一,与基质配比和植物种类有着密切的关系。通过模拟试验分析了以松树皮为覆盖层,陶粒为中间层强化污染物质吸附,轻石为底部透水层的生物滞留池中不同基质层配比时在运行过程中渗透系数的变化及植物的生长特性,探究了基质层对渗透性能的影响效果。结果表明:三者结构层比例为3∶11∶3(cm)时渗透系数和孔隙率均为最大,在松树皮∶陶粒∶轻石为2∶10∶3(cm)的配置下渗透系数最终所稳定的数值最高,在0.02 cm/s左右,更适宜于生物滞留池的运行,同时也最适合旱伞竹植物的生长。

Permeability is one of the important factors affecting the decontamination capacity of biological retention system in low impact development facilities in Sponge City,which is closely related to plant species and matrix ratio.Through simulation test,this paper analyzed the changes of permeability coefficient and plant growth characteristics in the biological detention tank with pine bark as the covering layer,ceramsite as the middle layer to strengthen the adsorption of pollutants and light stone as the bottom permeable layer,and explored the effect of the substrate layer on the permeability.The results showed that when the ratio of the three structural layers was 3∶11∶3(CM),the permeability coefficient and porosity were the largest.When the ratio of pine bark∶ceramsite∶light stone was 2∶10∶3(CM),the final stable value of permeability coefficient was the highest,which was about 0.02cm/s.It is more suitable for the operation of biological detention tank and the growth of umbrella bamboo plant.