利用生态混凝土控制城市坡面暴雨径流污染试验研究

利用生态混凝土作为护坡材料,研究暴雨条件下生态混凝土控制山坡降雨径流污染的机理,以期对生态混凝土在城市护坡和护岸中的应用提供理论依据.研究结果表明,生态混凝土改变了雨水在坡面上的水文过程,阻延径流作用十分明显,有效地降低了污染物的负荷输出.生态混凝土试验小区(T2)与裸地(CK)和改良土壤小区(T1)相比,径流量分别减少了48%和24%,TN年度污染负荷(UPLRs)分别减少了53%和45%,溶解态氮(DN)减少了26%和28%,TP减少了57%和30%,溶解态磷(DP)降低了80%和33%,COD降低了62%和40%,TSS降低了56%和43%,产流时间和流量峰均明显滞后.另外,同植被覆盖良好的小区(T3)相比,生态混凝土对各种污染指标的控制效果没有明显差异,但其抗冲刷能力较强,更能适应城市护坡和护岸的需要.

Application of eco-concrete for controlling stormwater pollution from urban sloping-land

To apply eco-concrete to protecting urban sloping-land and river bank,a study on control mechanism of eco-concrete for sloping-land stormwater pollution was carried out in Wuhan City Zoo in 2004.The results showed that eco-concrete could effectively change the hydrological process by delaying the generation of runoff obviously,and make the export amount of pollutant load decrease sharply.Compared with no-vegetation soil(CK)and improved soil plots(T1),the reduced rates of runoff volume in eco-concrete plot(T2)were 48% and 24%,and the unit pollution load rates(UPLRs)of total nitrogen(TN)reduced were 53% and 45%,dissolved nitrogen(DN)80% and 33%,total phosphorous(TP)57%and 30%,dissolved phosphorous(DP)80% and 33%,chemical oxygen demand(COD)62% and 40%,and total suspended solids(TSS)56% and 43%,respectively.The generating time and flow peak were also behind to the other plots.Compared with plant plot(T3),there was no difference of control efficiency and the eco-concrete is much better for protecting sloping-land and river bank from eroding by flooding in urban areas.