Abstract:
The COVID-19 pandemic has brought about significant changes in waste management globally, including the need for effective management of waste from used face masks (FM) to address environmental concerns. Using a composite binary admixture (CBA) of geopolymerized quarry dust (QD), bagasse ash (BA), and FM as fiber reinforcement, a novel soil treatment technique is suggested in this research to improve the mechanical properties of fat clay. As NaOH is an alkaline activator and Na2SiO3 is a catalyst for geopolymerization, these two ingredients were combined. These additives were optimized with the use of consistency limits, and an optimal binary additive was made by blending the optimal proportions of geopolymerized QD and BA. Extensive geotechnical testing, including unconfined compression tests, California bearing ratio tests, and 1D consolidation tests, at varying cures and percentages of FM, is used to evaluate the performance of the OBA with that of the planned OBA + FM. After OBA treatment, the soil's ductility is considerably decreased, making it more susceptible to sudden failure and instability under dynamic loadings. The development of (N, C)-A-S-H gel is responsible for the enhanced mechanical properties. FM fibers added to treated soil have been found to improve the strength characteristics beyond those of OBA, as well as control the ductility and deformability of the soil. Furthermore, scanning electron microscopy, x-ray diffraction analysis and energy dispersive x-ray spectroscopy were used to examine the microstructural alterations that occurred. The addition of OBA and the subsequent production of (N, C)-A-S-H gel completely affected the microstructure of the treated soil, as confirmed by these analyses. This research contributes to the development of low-cost filler/foundation materials, the elimination of waste issues associated with COVID-19 FM, and the preservation of natural habitats.
