Clogging processes of permeable paver systems under different maintenance methods in Beijing

ObjectiveAs one of the promising stormwater management practices, permeable paver systems are more and more widely used in the sponge city constructions. However, due to the lack of long-term monitoring data, the clogging processes of permeable paver systems and the recovery effects of maintenance methods are not clear. Based on the laboratory experiments, the clogging processes of permeable paver systems under different maintenance methods were measured and analyzed.

MethodBased on inflow-infiltration experiments, long-term changes in permeable pavement permeability and grain size distributions of bedding layers were measured and analyzed for three permeable pavement systems maintained with different methods including non-cleaned, vacuuming suction and high pressure washing.

Result Under three permeable pavement methods, the permeabilities decayed exponentially. After 7 years, the infiltration rates were 26, 229 and 19 mm/hour, respectively for non-cleaned, vacuuming suction and high pressure washing, which attenuated 99.6%, 96.3% and 99.7% of the newly-installed systems. Vacuuming suction was preferable to pressure washing in the long-term performances of permeable paver systems. The removal efficiencies of suspended solids of permeable paver systems ranged between 95%−98% with no significant differences among three systems (P < 0.05, n = 7). The contents of fine particles (0−200 μm) in the upper layers of old bedding layers increased by 15.6%−29.2% compared with the new bedding layers. The infiltration rates of “new paver + old bedding layer + old geotextile” were 28.3%−32.4% of the newly-installed systems for the replacement of old bedding layers and geotextiles in permeable paver systems. While the infiltration rates could recover to 63.8%−72.6% in the “old paver + new bedding layer + new geotextile” systems.

ConclusionTherefore, the measures of periodic maintenance of vacuuming suction and the renewal of bedding layers and geotextiles can be considered to obtain better permeability and recovery effect of permeable paver systems.