Sustainable Use of Recycled-Glass Powder in Soil Stabilization

Abstract

This study investigates the performance of sustainable use of recycled-glass powder (GP) in soil improvement. The porosity/cement ratio (η/Civ) and curing time are employed to study the evolution of unconfined compressive strength (qu) and durability against wet–dry cycles (measuring of loss of mass) of a sedimentary silty soil of Guabirotuba formation, stabilized with GP and cement, in Southern Brazil. Three dry unit weights of molding (γd), three cement contents (C) between 3% and 9%, and curing times of 7, 28, and 90 days are used to study the influence of GP content (i.e., 5%, 15%, and 30% by weight) and η/Civ index on qu and accumulated loss of mass (ALM) of the compacted blends. The long-term strength improvement and durability are observed and well-fitted to a power function depending on the η/Civ ratio. When γd, GP, and C are increased and the initial porosity (η) is reduced, qu strength and durability increase for all GP contents. The η/Civ ratio can also establish the empirical ratios between qu-ALM dependent on the GP contents used during compaction of the specimens. Finally, equations for dosing and estimating qu and ALM are obtained and set to 96.5% with a 6% error. Thus, all strengths and ALM percentages show the same normalized (i.e., divided) potential trend as the functions of GP, C, and γd, compatible for the value of η/Civ0.20=37.5% by volume, and it may be possible to extend it to other compacted blends proposed in the recent literature, such as soil-lime and soil-cement-roof tile waste.