LCA Framework for Utilization of Excavated Granulates in Pavement Systems

Abstract

Due to exponential increase in urbanization, there is a huge demand for aggregates in industry for construction of buildings and roadways. This in turn has accelerated quarrying from large rock formations, causing significant impacts on the ecosystem. Thus, there is a need to explore and develop alternative materials to meet the goals of sustainable infrastructure. Therefore, the major objective of this research was to formulate a lifecycle assessment (LCA) framework to investigate the environmental benefits of utilizing excavated granulates (EG) found within the soil deposits at the Indian Institute of Technology Tirupati during earthwork activities as replacement for virgin aggregates in the base layers of pavement systems. To accomplish the objective, a cradleto-laid LCA approach was adopted as per ISO 14040 and ISO 14044. The LCA results showed that utilization of EG instead of virgin aggregates in pavement sub-base resulted in reduction of human health risk, global warming, and terrestrial eco-toxicity by 43.5%, 52%, and 68%, respectively. Sensitivity analysis showed that material production phase had the highest impact on environment for EG as well as virgin aggregates followed by material transportation and construction phases. The use of EG will not only alleviate the high environmental burdens associated with mining activities but also help conserve the depleting natural aggregate resources. Additionally, the use of EG in pavements will provide an alternative for disposal of these naturally occurring rock masses. It is envisioned that the outcomes obtained in this study will be used as a benchmark to initiate the process of utilizing EG in pavements. Furthermore, the systematic framework presented in this study will certainly help policymakers in the decision-making process and promote the development of similar LCA studies for site-specific conditions, specifically to create smart village ecosystems that call for utilization of local resources to create products that promote sustainable development.