Experimental studies of the dilution of vehicle exhaust pollutants by environment-protecting pervious pavement

Abstract

This study determines whether environment-protecting pervious pavement can dilute pollutants immediately after emissions from vehicle. The turbulence-driven dry-deposition process is too slow to be considered in this aspect. The pavement used is the JW pavement (according to its inventors name), a high-load-bearing water-permeable pavement with patents in over 100 countries, which has already been used for more than 8 years in Taiwan and is well suited to replacing conventional road pavement, making the potential implementation of the study results feasible. The design of this study included two sets of experiments. Variation of the air pollutant concentrations within a fenced area over the JW pavement with one vehicle discharging emissions into was monitored and compared with results over a non-JW pavement. The ambient wind speed was low during the first experiment, and the results obtained were highly credible. It was found that the JW pavement diluted vehicle pollutant emissions near the ground surface by 40%-87% within 5 min of emission; whereas the data at 2 m height suggested that about 58%-97% of pollutants were trapped underneath the pavement 20 min after emission. Those quantitative estimations may be off by +/- 10%, if errors in emissions and measurements were considered. SO2 and CO2 underwent the most significant reduction. Very likely, pollutants were forced to move underneath due to the special design of the pavement. During the second experiment, ambient wind speeds were high and the results obtained had less credibility, but they did not disprove the pollutant dilution capacity of the JW pavement. In order to track the fate of pollutants, parts of the pavement were removed to reveal a micro version of wetland underneath, which could possibly hold the responsibility of absorbing and decomposing pollutants to forms harmless to the environment and human health.

Influence of stratigraphy and slope on the drainage capacity of permeable pavements: laboratory results

“…The permeable pavements investigated in the present research study are the most common and largely installed in urban areas especially for the construction of parking lots (Liu et al 2012, Wardynski et al 2012. In particular, the selected typologies are characterized by an open cell paver realized with concrete blocks and a pervious paver made with pervious concrete bricks.…”

Measurement of Permeability and Comparison of Pavements

“…In addition to the common permeable pavement systems mentioned, the JW Eco-technology also recently gained attention. The JW Eco-technology pavement has been described in the literature as a load-bearing pavement because of its unique structure and design [3,57,58]. The JW Eco-technology product was first installed in the USA at the University of Illinois (Urbana-Champaign) in 2016, and it may provide a permeable pavement alternative that has the necessary structural strength needed for roadways, while also providing stormwater management and other environmental benefits.…”

“…The interior of each aqueduct surface is smooth, to allow surface water to flow directly along the interior wall downward to the subsurface layer. The JW Eco-technology prevents the occurrence of lateral flow that is seen in most permeable pavement systems [57]. Depending on the location and objective of a paved area, the design of the pavement using JW Eco-technology may vary.…”

“…A prescribed number of JW Eco-balls, or plastic hollow balls that increase the storge capacity of water, are distributed throughout the gravel layer. The JW Eco-technology has been tested successfully for 10 years at selected locations in Taiwan [3,57,58]. In Taiwan, JW Eco-technology pavement has been used for street sidewalks, pedestrian walkways, outdoor parking lots, squares, pedestrian walkways, and basketball courts.…”

“…In Taiwan, JW Eco-technology pavement has been used for street sidewalks, pedestrian walkways, outdoor parking lots, squares, pedestrian walkways, and basketball courts. In addition, it has been installed at a harbor loading area where container trucks have run frequently for years The air-circulating aqueduct openings are evenly distributed among the concrete unit, approximately 100 pores per square meter [3,57]. The interior of each aqueduct surface is smooth, to allow surface water to flow directly along the interior wall downward to the subsurface layer.…”