Clogging effects of portland cement pervious concrete

Portland Cement Pervious Concrete (PCPC) is a unique and effective mean to solve the important environmental issues and to support green, sustainable growth, by reducing stormwater and providing treatment of pollutants contained within. As a replacement for conventional impermeable pavement, PCPC has seen increasing used in recent year.\nClogging of PCPC leading to potential problems in serviceability has been regarded as one of the primary drawbacks of PCPC systems. The clogging potential of three void ratios of pervious concrete were examined using three different soil types: sand, clayey silt and clayey silty sand. Pervious concrete cylindrical specimens were exposed to sediments mixed in water to simulate runoff with small and large load of soil sediments. Pressure washing, vacuuming and a combination of these were used as rehabilitation methods to clean the clogged specimens. The clogging tests were conducted using falling head permeability apparatus by allowing the "dirty water" to flow through the specimen. A clogging cycle included both clogging and cleaning procedure. The permeability was determined during the clogging procedure and after the cleaning procedure in each clogging cycle. 20 clogging cycles were repeated on each sample to simulate the 20 years of pavement service life.\nThe results show that permeability reduction magnitude as well as rate and permeability recovery by rehabilitation are significantly affected by sediment types, void ratios of specimens, and selection of rehabilitation methods. The results provide a quantitative evaluation of the clogging effect of pervious concrete, and the comparison of tested rehabilitation methods in terms of permeability recovery.