Guidelines for Pervious Concrete Sidewalks, Parking Lots, and Shared-Use Paths to Improve Driver, Biker, and Pedestrian Safety

Abstract

The surface frictional properties of pervious concrete (PC) slabs were evaluated by using a British Pendulum Tester (BPT) with two different rubber sliders that represented driver and pedestrian users. The volumetric air content at the finished surface of the slabs was quantified by image analysis to identify any possible correlations between the different surface finishes due to varied porosity and the microtexture of the PC slabs. Frictional evaluation for all the PC slabs was compared with that of traditional portland cement concrete (PCC) slabs under three baseline conditions: dry, wet, and iced. The iced condition was then treated with magnesium and calcium chloride (MgCl2 and CaCl2), used once as anti-icing and again as de-icing agents, and then individually tested by using the BPT. Friction values were recorded as the British Pendulum Number (BPN). Minimal correlation was found in this study between porosity and BPN. The PC slabs showed significantly higher BPN values than the PCC slabs in each of the baseline conditions for the mixture tested in this study. For one icing event, the one-time application of anti- and de-icing agents on PC slabs improved the friction of the PC slabs to the allowable BPN level using both MgCl2 and CaCl2.