Long-Term Field Monitoring and Evaluation of Maintenance Practices for Pervious Concrete Pavement in Vermont

Pervious concrete pavement (PCP) is used because of its unique properties that allow water to infiltrate into the surface. The objectives of the study reported in this paper were to observe the performance of PCP in the field, determine the effectiveness of cleaning methods to restore infiltration rates, and compare field observations with laboratory results when possible. Two PCP sites in Vermont were monitored over a year through the measurement of infiltration rates at several locations. Facility-wide cleaning operations, such as street sweeping and vacuum-truck cleaning, were tested for their capability to restore infiltration rates. Spot-cleaning methods, such as hand vacuuming, pressure washing, and a combination of the two, were also tested. Infiltration rates decreased gradually during the monitoring period, with average reductions of 59% at the first facility and 26% at the second. Street sweeping and vacuum-truck cleaning restored infiltration rates by 21% and 30%, respectively, but could not restore severely clogged areas. Spot-cleaning methods increased infiltration rates by 85% after pressure washing, 10% after vacuuming, and 100% after pressure washing followed by vacuuming. Vacuum-truck cleaning was recommended. Either method, however, should be used for maintenance operations and should be started after construction. Spot-cleaning methods, with the exception of vacuuming, restored infiltration rates of severely clogged areas and were recommended for localized cleaning. Long-term monitoring compared reasonably well with that of earlier studies, whereas the results associated with cleaning were substantially lower than those found in the literature.