Sustainable Soil Stabilization Using Fly Ash and Slag-Based Geopolymers: A Synthesis of Strength Development,Durability and Soil-Dependent Behavior

The growing demand for environmentally sustainable soil stabilization has increased interest in alternatives to ordinary Portland cement (OPC),whose production is associated with high energy consumption and carbon emissions.Regarding this,industrial by-products such as fly ash (FA) and ground granulated blast-furnace slag(GGBS) offer considerable potential as precursors for geopolymer-based soil stabilization.This study presents a comparative synthesis of experimental studies on FA and FA–GGBS-based geopolymer stabilization of weak and problematic soils.The studies are systematically analyzed based on precursor composition,binder content,alkaline activator,curing conditions,soil characteristics,strength development and durability to assess their influence on stabilization performance.The synthesized results show that optimized geopolymer mixtures substantially improve soil strength and durability.For example of experiments,FA stabilization increased 7-day UCS from 0.112 MPa to 1.390 MPa, while incorporating GGBS increased UCS from 609 to 1377 kPa.The analysis indicates that the stabilization performance depends on appropriate proportions of precursor materials and activator,while GGBS can further promote strength development and durability.As like ,a small percentage of geopolymer can improve the soil strength.Overall,FA–GGBS-based geopolymer stabilization demonstrates strong potential for improving soil strength,stiffness and stability while reducing reliance on conventional cement and promoting the beneficial utilization of industrial by-products.