生态透水混凝土对路面径流污染阻滞效果

作为典型的大孔隙铺装材料,生态透水混凝土不仅能够快速渗透路表雨水,防止积水产生,还能有效阻滞路表径流中携带的大量污染物。以目标孔隙率为20%、加入陶粒和硅藻土两种净化材料的生态透水混凝土为研究对象,以性能测试结果为评价指标,分析净化材料掺量对生态透水混凝土孔隙率、渗透系数的影响;以污染物去除率为检测指标,分析不同净化材料掺量对径流污染阻滞效果的影响并从微观层面加以解释;以污染物总量为控制指标,采用室内加速试验,模拟生态透水混凝土在8 a服役期内孔隙率、渗透系数及污染物去除率的变化规律,研究其在长期服役过程中结构孔隙的阻塞过程。研究结论表明,生态透水混凝土中陶粒的最佳掺量为10%,硅藻土的最佳掺量为20%;从物理电子显微镜和化学元素分布两个层面确认了生态透水混凝土对道路径流污染物良好的阻滞作用;随着生态透水混凝土模拟服役年限增长,其孔隙率和渗透系数均衰减,对各污染物的阻滞效果也有着对应的变化趋势。

The Study of Blocking Effect of Ecological Permeable Concrete onthe Road Runoff Pollutants

As a typical large-gap paving material, the ecological pervious concrete can not only quickly infiltrate the surface rainwater and prevent the accumulation of water, but also effectively remove a large amount of pollutants carried in the surface runoff. In this study, the target of 20% of the porosity, adding ceramic and diatomite two kinds of purified material of the ecological water-permeable concrete for the study, using performance test results as evaluation indicators, analyze the influence of the amount of purification materials on the porosity and permeability coefficient of ecologically permeable concrete. Using the pollutant removal rate as a detection index to analyze the effect of different purification materials on the effect of runoff pollution retardation and explain it from the microscopic layer. Taking the total amount of pollutants as the control index, the indoor accelerated test was used to simulate the change of porosity, permeability coefficient and pollutant removal rate of ecological permeable concrete during the 8-year service period. In this way, the blocking process of structural pores during long service has been studied. The research conclusion indicates that the optimum content of ceramsite is 10% while The optimum content of diatomite is 20%. From the physical electron microscope and the distribution of chemical elements, it is confirmed that the ecologically permeable concrete has a good retarding effect on the path flow pollutants. With the increase of service life of ecological permeable concrete, both porosity and permeability coefficient decrease, and the purification effect of each pollutant has a corresponding change trend.