Rutgers University engineers have shown that permeable concrete pavements could help reduce the ‘urban heat island effect.’
According to this study, the urban heat island effect is often responsible for making cities to sizzle in summer. And the real culprit causing this is the impermeable pavement.
Impermeable pavement made of concrete or asphalt covers more than 30% of most urban areas and can exceed 140 degrees Fahrenheit in the summertime.
It indirectly increases peak demand for energy in the summertime, air conditioning costs, air pollution and greenhouse gas emissions, heat-related illness and deaths, as well as water pollution.
One way of remedying this is by using permeable concrete that is said to be highly effective in handling heat.
Permeable pavement contains large connected pores, allowing water to drain through and reducing pavement temperature.
Water in pores will also evaporate, reducing pavement surface temperature.
Moreover, permeable concrete pavement does a better job reflecting heat than asphalt pavement.
The Rutgers study found that permeable concrete pavement gives off slightly more heat on sunny days compared with conventional concrete pavement, but 25% to 30% less heat on days after rainfall.
The engineers then improved the design of permeable concrete with high thermal conductivity – meaning it can transfer heat more quickly to the ground – further reducing heat output by 2.5 percent to 5.2 percent.
According to the engineers, incorporating industry byproducts and waste such as fly ash and steel slag into permeable concrete can further increase its economic and environmental benefits.
Image and content: Hao Wang/Rutgers University-New Brunswick
