雨水径流颗粒物对陶瓷透水砖堵塞的影响

Impacts of rainwater runoff particles on clogging of ceramic permeable brick

通过雨水径流水质的实地检测,分析了雨水径流中颗粒物粒径分布规律;采用室内试验模拟了雨水径流引起的陶瓷透水砖堵塞过程,系统研究了雨水径流中颗粒物对陶瓷透水砖堵塞的影响。结果表明:雨水径流中的颗粒物绝大部分平均粒径小于50μm;陶瓷透水砖堵塞机制主要是粒径20~<50μm的颗粒物引起的表面堵塞,砖表面截留的颗粒物质量约占总截留颗粒物质量的75%;陶瓷透水砖表面截留颗粒物的粒径范围与砖表面孔径范围并不一致,主要是因为陶瓷透水砖截留的颗粒物在其表面形成的“类滤膜”的筛滤截留作用。建议合理减小陶瓷透水砖小于50μm范围的孔径占比,以提高人工清扫恢复陶瓷透水砖透水性能的效率。

The size distribution laws of particles in rainwater runoff were analyzed through field measurement of rainwater runoff quality.The impacts of rainwater runoff particles on the clogging of ceramic permeable brick were systematically investigated employing laboratory tests where the process of the clogging of permeable brick resulted from rainwater runoff was simulated.The results show that the average sizes of most particles in the rainwater runoff are less than 50μm.The surface clogging caused by particles with sizes of 20~<50μm is the main clogging mechanism of ceramic permeable bricks,and the mass of particles intercepted on the surface contributes 75%to the total mass of particles intercepted in the bricks.The size range of intercepted particles on the brick surface isn’t consistent with the pore size range of the superficial brick,which is mainly caused by the filtration interception of formed filter membrane on the permeable brick surface by intercepted particles.The proportion of pore size under 50μm of a permeable brick is suggested to be reasonably reduced to improve the permeability recovery of a permeable brick by manual cleaning.