Utilization of Recycled Materials in Constructing Stone Columns for Sustainable Soil Improvement-State of The Art

Stone column technique is widely recognized for soil improvement, whose construction relies on natural materials, leading to challenges such as resource depletion and environmental concerns. This emphasizes the importance of exploring diverse materials to optimize the performance and sustainability of stone column applications in geotechnical engineering. This paper reviews the properties and the behaviors of a range of alternative recycled materials that could potentially replace natural aggregates used to construct stone columns. These materials include recycled concrete aggregates, recycled asphalt pavement (RAP), tire chips, expanded polystyrene (EPS) geofoam, and lightweight aggregates. As a baseline, the properties and the behaviors of natural aggregates used in stone columns are also reviewed, focusing on physical, mechanical, and environmental characteristics required by various standards and regulations. Also, the geotechnical properties and the behaviors of the recycled materials available in the literature were reviewed, to assess their viability in stone column applications. Furthermore, a comparative analysis is presented, highlighting the advantages and disadvantages of using recycled materials versus natural aggregates in stone columns, including environmental impact and cost-effectiveness. The outcomes of this paper include compiling a database for the properties of natural and recycled materials used in stone column construction, which will help practicing engineers to design stone columns and aid researchers to advance research front in this important multidisciplinary area. This will lead to a more comprehensive understanding of the potential for recycled materials in geotechnical engineering applications, and contribute to more sustainable and cost-efficient construction practices for soil improvement solutions.