Evaluation of surface infiltration rate of permeable block pavements using single-ring infiltrometer

Abstract

The increase in urban flooding has been attributed to the change in stormwater pattern due to climate change as well as the increased impervious coverage following rapid urbanization. The permeable block pavement is one of most widely accepted Green Infrastructure and Low Impact Development facilities for runoff mitigation in urban area where land is generally covered with pavement roads and parking lots. To assess the applicability of single-ring infiltrometer to permeable block pavements, the permeable block pavements with two different joint filler materials constructed in Korea Green Infrastructure and Low Impact Development Center were selected and tested using 300 mm single-ring infiltrometer based on ASTM C 1701. The second measurement sequentially taken after the first measurement gave smaller infiltration rate than the first with few exceptions, because the suction in the system is lost while taking the first measurement. No meaningful dependency of infiltration rate on spatial variation of measurement locations was found from the data. The number of crossing joints or the pattern of blocks tested within the infiltrometer was found to be one of governing factors. One should carefully choose the test domain and pattern contained within the infiltrometer to estimate the infiltration rate which represents the entire domain of block pavements. The infiltration rate of the pavement with coarse filler (Ø 4–8 mm) was about three times the infiltration of the system with finer filler (Ø 2 mm). However, when coarse filler is used, the construction should carefully be conducted as coarse fillers are harder to be uniformly installed into the joint gap with finite width.