Use of marginal and recycled fills for GRS structures

Slovenian National Building and Civil Engineering Institute (ZAG) Dimičeva 12, SI-1000 Ljubljana, Slovenia E-mails: stanislav.lenart@zag.si, ram.karumanchi@zag.si, web page: https://www.zag.si/

Abstract

Marginal and recycled fills are increasingly being utilized in geosynthetic reinforced soil (GRS) structures like retaining walls and bridge abutments due to their cost-effectiveness and sustainability. Marginal fills, including locally available soils with less desirable engineering properties, can be used when properly engineered with geosynthetics to enhance strength and stability. Recycled fills, such as recycled concrete, asphalt, various ashes have been proved already as an eco-friendly alternative to conventional aggregates. However, these practices involve thorough characterization and testing of marginal and recycled fills to ensure their suitability for specific applications. Advanced geotechnical analyses, including laboratory tests and numerical modeling, help determine the optimal blend of materials and reinforcement for achieving desired performance criteria. Experiences with the use of residues from deinking paper industry and river debris as backfill material are presented. Time effect on the compaction and deformation characteristics as well as the impact of high basicity of backfill material have been considered.