An Evaluation of Cool Pavement Strategies on Concrete Pavements

With a view towards sustainability and eco-friendliness, the paving industry is now more interested in incorporating better pavement materials and pursuing strategies that will result in greener and longer lasting highways. Temperature plays a crucial role in the long-term performance of pavements. High temperature in pavements contribute to the urban heat island (UHI) effect and reduction of pavement life. In concrete pavements, the development of large temperature and moisture differentials during both daily and on a seasonal basis can produce warping and curling stresses. If these stresses exceed the flexural limits of the rigid pavement they may lead to the formation of structural cracks. In asphalt pavement, higher temperatures may deteriorate the viscoelastic property of asphalt binders and may lead to reduced stiffness and rutting. This study evaluated three surface treatment methods as cool pavement strategies to reduce temperature in concrete pavements. Geosynthetic reinforced chip seals (GRCS) with high albedo aggregate and lightweight aggregate impregnated with phase change material (PCM), and thin hot mix asphalt (HMA) layers were investigated. Temperature data were collected under simulated conditions in the laboratory. The results of these various surface treatment methods were compared to those from a control cement mortar sample. The results show that the GRCS with high albedo can be used as an effective strategy for reducing temperature in concrete pavements.