Innovative Utilization of Fly Ash in Geotechnical Engineering: An Analytical Review Supported by Extensive Geotechnical Testing

Abstract

Extensive study has been conducted on the use of fly ash as an additive in soil and geotechnical engineering projects due to its capacity to enhance soil properties and the efficacy of geotechnical structures. Various fly ash samples had distinct elemental compositions; nevertheless, the chemical analysis indicated that Sample 3 possessed the highest silica content (55%), which corresponded with enhanced pozzolanic reactivity. The physical property tests revealed significant disparities; for instance, Sample 2 exhibited the smallest particles at 18 microns, but Sample 5 had the highest specific gravity at 2.5. This indicates that the qualities of the soil may alter when mixing these samples. The maximum dry density climbed to 2050 kg/m³, and the cohesive strength to 25 kPa with higher quantities of fly ash, as shown by geotechnical testing findings, which also revealed trends in shear strength parameters and compaction characteristics with varying fly ash concentrations. These findings underscore the potential of fly ash in geotechnical applications for soil stabilization, compaction enhancement, and load-bearing capacity augmentation. Optimizing soil behavior becomes feasible via the judicious use of fly ash, as shown by the enhancements in soil engineering properties found. Fly ash may be used in a few geotechnical applications, yet proper evaluation of its composition and physical properties, any adverse environmental and structure interaction with time must be made before applying the product. The present research focuses on the fly ash as the soil adding material and the direction of its activating material to the geotechnical built environment contributes significant knowledge of its application.