A Decision Making Tool for Incorporating Sustainability Measures in Rigid Pavement Design

One of the most important tools in assessing rigid pavement design sustainability (or environmental impact) is a lifecycle assessment (LCA), which may be applied in any stage of a product’s lifecycle from cradle to grave, such as pavements. Although LCA was the focus of much research and codification by organizations such as the International Organization for Standards and the Society of Environmental Toxicology and Chemistry, limitations exist, such as a) LCA is time consuming; and b) the used data may become outdated, inaccurate, biased, incomplete, and/or expensive to use. These limitations are not a deficiency in LCA as a tool, but in the manner in which various researchers apply the limitations differently. The objective of this study is to develop a methodology to assess rigid pavement sustainability using Environmental Product Declarations (EPDs) as a quantification tool. EPDs are defined as quantified environmental data for a product, based on a pre-set category of parameters, defined in the ISO 14040 series of standards (ISO 14025). EPDs were established to homogenize assumptions while performing an LCA. In fact, EPDs follow the same LCA procedure for quantifying the environmental impact. However, the method used to issue an EPD importantly guarantees consistency in the data collection process, thus enabling a comparison between products by fulfilling the same function as well as limiting the discrepancies that could exist when different researchers perform an LCA. To achieve this objective, a new pavement design framework was developed to incorporate this sustainability evaluation criterion. After the design passes the technical evaluation, the framework will assess pavement sustainability outside the scope. The framework will enable alternative design comparison between various products, as well as product benchmarking that uses EPD as a data source. The scope includes a cradle to gate analysis (using EPD), as well as the transportation stage from the manufacturer’s location to project location. The transportation stage from the manufacturer’s location to project location was assessed using LCA. Various case studies will be provided to validate the new framework. The framework was used to assess the total sustainability score of various alternatives in terms of which one has a higher/ lower score. However, these differences were insignificant. Results also proved that the transportation stage represents an important criteria, and the total environmental impact was sensitive to a change in this factor