A method to select a road pavement structure with life cycle assessment

摘要

Decision-making for investments in infrastructure has always proved to be a challenge due to the number of variables to be considered when selecting projects. Specifically, in flexible road pavement works, the methods adopted for this purpose traditionally use technical and economic criteria (nature of materials and execution techniques). However, given the need to optimize the use of natural resources, it is understood the importance that other parameters, such as sustainability, are also used in decision making for investments in infrastructure. Besides, advances in engineering studies have enabled methodologies, such as mechanistic-empirical design, to be developed to more accurately estimate the useful life of paving structures. Because of this scenario, it is understood that a methodology that makes use of the Life Cycle Assessment of the structure, aiming to evaluate the useful life of the pavement, combined with the Data Envelopment Analysis technique for compatibility of the alternatives, shows itself as a viable tool to assist decision-making when choosing flexible road paving projects. Therefore, the present study aims to offer a method for the selection of flexible road pavement structures, composed of four major stages: pavement design, construction costs analysis, life cycle impact assessment (LCIA) and integration of LCIA with construction costs. Finally, for the case study analyzed in Brazil, the pavement composed of a bitumen stabilized base, containing 15% recycled material (waste tire rubber), in the design criterion of 30% of the cracked area, would be the best option within the scenario cost and environmental impact assessment, which included the use of natural, cementitious and bitumen stabilized materials. For other design criteria, the method allows a sensitivity assessment of the efficiency of the analyzed pavement types, showing that a determined pavement structure may lose its presumed primacy of choice due to this design parameter. (C) 2020 Elsevier Ltd. All rights reserved.