An Experimental and Numerical Study Exploring the Potential of Stabilized Landfill Mined Soil-Like Fraction for Foundation Fill Application
Authors :- Sandeep Reddy, A., Mistry, K., Iyer, K.K.R., Dave, T.N.
Publication :- Proceedings of the Indian Geotechnical Conference (IGC 2024), Volume 2. IGC 2024, Lecture Notes in Civil Engineering, vol 708. Springer, 2025.
The reutilization of landfill mined soil-like fraction (LMSF) obtained from landfill mining is limited due to its heterogeneity, possible presence of heavy metals and organic matter. However, by adopting suitable treatment techniques, LMSF could be potentially reutilized as alternate material. In this context, efforts were made to stabilize LMSF using cement, lime, and magnesia activated slag. Unconfined compressive strength (UCS) tests and unconsolidated undrained triaxial tests were performed on stabilized LMSF cured for 7 and 28 days. LMSF stabilized with magnesia activated slag exhibited superior performance with a maximum 28 days UCS of 1000 kPa. Further, two-fold increment in peak deviatoric stress was observed with increase in confining stress from 0 to 150 kPa for magnesia activated slag stabilized LMSF. Exposure to 12 cycles of wetting and drying resulted in a cumulative mass loss of about 1.5%, 8%, and 20.5% for LMSF stabilized with magnesia activated slag, cement, and lime, respectively. Overall, LMSF stabilized with magnesia activated slag performed better in terms of strength, resistance to degradation and sustainability aspects. Furthermore, numerical studies using PLAXIS 2D were carried out to evaluate the effect of stabilized LMSF in enhancing bearing capacity of a 2 m square footing resting on soft clay. An increase in bearing capacity of about 51.27% and 84.29% was observed with 1 m replacement of soft clay with LMSF and magnesia activated slag stabilized LMSF, respectively. Overall, the study findings are encouraging terms of exploring potential utilization of LMSF for fill applications, with careful attention to challenges associated with LMSF.