This article has multiple issues. Please help
improve it or discuss these issues on the
talk page. (
Learn how and when to remove these template messages)
|
Cool pavement is a road surface that uses additives to reflect solar radiation unlike conventional dark pavement. Conventional dark pavements contribute to urban heat islands as they absorb 80–95% of sunlight and warm the local air. [1] Cool pavements are made with different materials to increase albedo, thereby reflecting shortwave radiation out of the atmosphere. Increasing albedo reduces heat transfer to the surface and can hypothetically cause local cooling if the spatial scale of the albedo reduction is sufficiently large. The EPA reports "that if pavement reflectance throughout a city were increased from 10 to 35 percent, the air temperature could potentially be reduced by 1°F (0.6°C)." [2] Existing dark pavement can be altered to increase albedo through whitetopping or by adding reflective coats and seals. New pavement can be constructed to increase albedo by using modified mixes, permeable pavements, and vegetated pavements. [3]
The composition of cool pavements is engineered to enhance albedo through the use of reflective aggregates, advanced binders, and surface coatings. Reflective aggregates like quartz, limestone, or granite are chosen for their high reflectivity, improving the pavement's ability to reflect sunlight. [4] Advances in binder technology have introduced eco-friendly options such as tree resin, which lowers surface temperature by reflecting more sunlight and offers a sustainable alternative to petroleum-based bitumen.
In concrete pavements, the use of white cement or light-colored slag further increases reflectivity. White cement, lacking the iron and manganese oxides of traditional Portland cement, enhances sunlight reflection. Light-colored slag, a byproduct of iron and steel production, when integrated into concrete, improves reflectivity, structural integrity and environmental durability. [5]
These material choices in cool pavements significantly raise their albedo, contributing to cooler surfaces and mitigating urban heat islands, emphasizing sustainability in urban development.
{{
cite journal}}
: Cite journal requires |journal=
(
help)
This article has multiple issues. Please help
improve it or discuss these issues on the
talk page. (
Learn how and when to remove these template messages)
|
Cool pavement is a road surface that uses additives to reflect solar radiation unlike conventional dark pavement. Conventional dark pavements contribute to urban heat islands as they absorb 80–95% of sunlight and warm the local air. [1] Cool pavements are made with different materials to increase albedo, thereby reflecting shortwave radiation out of the atmosphere. Increasing albedo reduces heat transfer to the surface and can hypothetically cause local cooling if the spatial scale of the albedo reduction is sufficiently large. The EPA reports "that if pavement reflectance throughout a city were increased from 10 to 35 percent, the air temperature could potentially be reduced by 1°F (0.6°C)." [2] Existing dark pavement can be altered to increase albedo through whitetopping or by adding reflective coats and seals. New pavement can be constructed to increase albedo by using modified mixes, permeable pavements, and vegetated pavements. [3]
The composition of cool pavements is engineered to enhance albedo through the use of reflective aggregates, advanced binders, and surface coatings. Reflective aggregates like quartz, limestone, or granite are chosen for their high reflectivity, improving the pavement's ability to reflect sunlight. [4] Advances in binder technology have introduced eco-friendly options such as tree resin, which lowers surface temperature by reflecting more sunlight and offers a sustainable alternative to petroleum-based bitumen.
In concrete pavements, the use of white cement or light-colored slag further increases reflectivity. White cement, lacking the iron and manganese oxides of traditional Portland cement, enhances sunlight reflection. Light-colored slag, a byproduct of iron and steel production, when integrated into concrete, improves reflectivity, structural integrity and environmental durability. [5]
These material choices in cool pavements significantly raise their albedo, contributing to cooler surfaces and mitigating urban heat islands, emphasizing sustainability in urban development.
{{
cite journal}}
: Cite journal requires |journal=
(
help)