Application of M-sand waste as a substitute to granular soil for embankment fills and backfills in earth walls Available to Purchase

Lot of fine dust particles are produced while manufacturing M-Sand which involves crushing of hard rocks to required fine aggregate sizes. These fine dusts are separated from M-Sand either by dry process or by wet process resulting in 2 types of M-Sand Wastes (MSW) – M-Sand Dust Waste (MSD) and M-Sand Sludge Waste (MSS). These MSW are dumped in landfills and available unused areas thus leading to waste of valued land areas. Also, these MSW in dry state are easily blown by wind causing air pollution and leading to serious breathing problems and health hazards to humans. These issues can be resolved by utilizing MSW in construction sector as additives / replacements in concrete or for soil stabilization. In this work, MSD and MSS have been used as a replacement to 3 types of granular soil: Silty Sand (SM), M-Sand and River Sand, which is generally preferred for filling purpose in embankments, retaining walls, earth reinforcement walls etc. The granular soil was substituted by MSW in weights of 20%, 40%, 60% and 80% by dry weight of soil. Effect of this replacement on the angle of internal friction (ɸ⁰) of granular soil was studied in detail by conducting Direct Shear Test (DST) in undrained condition and optimized proportion of granular soil:MSW was decided based on the investigational results. For most of the combinations of SM : MSW, M-Sand : MSW and River Sand : MSW, ϕ⁰ was found to be greater than 30⁰ and thus can be utilized for embankment filling purpose as per IRC: SP: 102-2014. Huge volumes of granular soil can be conserved if even a minor replacement of backfill soil with MSW is done thus resulting in a cost effective and sustainable construction.