Paper by WATHNE SMITH from ISCR 10th 2006 Brussels Belgium
Concrete pavements have long been considered the sustainable choice, simply due to their longevity. There are examples of both highways and local roads in North America where concrete pavements have lasted more than 50 years without significant maintenance. However, recent focus in North America on sustainable development and environmental stewardship in transportation has fostered the concept of Green Highways. Green Highways is a term used to describe highways that are environmentally responsible and sustainable in all aspects, including design, construction and maintenance. Concrete pavements can meet this requirement with its many sustainable benefits. For example, concrete pavements can be designed with pervious concrete shoulders that minimize surface-water discharge. Use of optimized surface textures allow for quieter pavements with excellent skid properties. Rolling resistance is reduced on properly textured concrete pavements as well. Incorporating recycled materials and industrial by-products into concrete mixtures, such as fly-ash and ground granulated blast furnace slag, reduces the load on virgin materials and conserves natural resources. The lighter color of concrete pavements reduces the power needed to adequately illuminate roads, and can help counteract the urban heatisland phenomenon. Finally, the documented durability and wear-resistance of concrete pavements ensure that the surface characteristics that contribute to quiet, fuel efficient and safe roadways remain intact for decades. This long term performance eliminates the need for frequent pavement resurfacing and rehabilitation, and the accompanying consumption of valuable resources. The North American concrete paving industry feels that concrete pavements are the clear choice for economically sustainable and environmentally sensitive roadways truly Green Highways, in more ways than one.