Cost Analysis for the Application of Recycled Materials in Road Subgrade Layer: A Case Study in Egypt

Egypt’s construction industry has lately experienced rapid growth, particularly for infrastructure and road projects. This expansion has exacerbated a pressing issue: the accumulation of Construction and Demolish Wastes (CDW). To tackle this challenge, there is a growing proposal to recycle CDW in construction projects. This research aims to assess the economic and environmental implications of integrating recycled materials into road subgrade layers, contrasting their benefits with those of natural materials. The research methodology involved a comprehensive analysis of subgrade material characteristics based on Egyptian code requirements. A comparative analysis was conducted to evaluate the economic and environmental impacts of using natural versus recycled materials. Economic factors related to natural materials encompass the costs of raw materials, production processes, and transportation, while recycled materials offer the additional economic benefit of reclaiming landfill areas, significantly influencing overall cost assessments. Environmental costs, including resource depletion and emissions from production and transportation, were also considered. To facilitate these analyses, a VBA modeling tool; Cost Impact of using Recycled Materials in Roads (CIRMR) was developed, incorporating insights from prior research. Through a real application case study, the findings indicate that the net economic cost of using recycled materials yields an impressive 888% return compared to natural materials, primarily driven by reclaimed landfill value. Furthermore, the net environmental cost impact demonstrates a remarkable 3522% return due to reduced carbon emissions from CDW recycling. These findings offer valuable insights for decision-makers in Egypt, emphasizing the potential for enhancing CDW recycling initiatives and promoting sustainable construction practices.