Quantification of Impact of the Use of Recycled materials on Energy and Greenhouse Gas Emission

Sustainable development is defined as a development that meets the needs of the present without compromising the ability of future generations to meet their own needs. The sustainability consists of three components: cost, environment and energy. Transportation sectors, including construction of highway and bridges, accounts for significant energy consumption and greenhouse gas emission. However, current standards and decision tools do not adequately address all three sustainability components. For instance, while pavements are heavy users of recycled material, they are not intently built to minimize emissions, energy use and, sometimes, environmental impact. Traditionally, the decision-making to select a material is primarily based on engineering performance and economy. However, it has become obvious that energy and environment should also be included in the decision-making. One of the barriers is that, unlike engineering performance and costs, there is a lack of vigorous quantitative evaluation of energy and environment impacts. A quantitative characterization of energy and environment impacts by the use of recycled materials is needed to facilitate the comprehensive analysis or green highway rating. This paper addresses the impacts of the use of recycled asphalt pavement in hot mix asphalt and use of recycled asphalt pavement as base course.