Evaluation of the geotechnical characteristics of landfill mined soil like fraction (LMSF) for sustainable fill application

Landfill-mined soil-like fraction (LMSF) is the fraction of legacy municipal solid waste (MSW) obtained from landfill mining. LMSF is emerging as a potential sustainable fill material, due to its soil-like particle size distribution, and availability in large quantities in towns/cities. However, very limited efforts have been made in earlier studies to evaluate the geotechnical properties of LMSF and to ascertain its suitability as a sustainable fill material for various infrastructure projects. In this regard, the present study conducts a detailed experimental investigation to evaluate the physical, chemical, mineralogical, and geotechnical properties of LMSF. It has been noted that the physical properties of LMSF are comparable to well-graded sand with gravel; however, the presence of organic matter introduces some cohesion and compressibility in LMSF. The evaluation of the geotechnical properties of LMSF suggests favourable shear strength characteristics with low compressibility; while the maximum dry unit weight has been observed to be relatively low. It is inferred from the study that LMSF with/without stabilization can be utilized as a potential fill material for different applications such as embankment, reinforced wall, subgrade improvement, general backfill, filling of low-lying areas and structural fill applications for low to moderate loading. Efforts have also been made to understand the sustainability aspects related to the utilization of LMSF in terms of environmental, social, and economic benefits, along with the challenges associated with LMSF. The findings of the study are quite encouraging for exploring LMSF as a sustainable fill material, a small step towards building sustainable infrastructure for the future.