Impact response of cementitious composites incorporating waste glass and untreated PVA fibers

Significant amount of literature studies revealed possible opportunities to recycle waste glass (WG) in concrete construction as a filler material or as a cement substitution. The aim of this study is to evaluate the possibility silica sand replacement by fine waste glass (WG), partially or completely, and to investigate its particular effect on repeated impact strength of cementitious composites. Four plain mixtures and four similar mixtures reinforced with low-cost untreated PVA fibers were tested. The first mixture of each group included no WG, while the WG replacement ratios of the other three mixtures were 30, 60 and 100%. The repeated impact testing setup recommended by the ACI 544-2R was the main investigated mechanical property, while compressive strength and splitting tensile strength were also tested for the produced mixtures. The test results indicated a positive effect for the PVA fibers on the mechanical properties. The incorporation of WG improved the compressive strength of plain mixtures by approximately 4-10% but negatively affected the fibrous mixtures, while it decreased the splitting tensile strength for all mixtures by approximately 2-12%. Using WG increased the impact strength for all mixtures with percentage increases ranged from 2 to 62% for plain mixtures and 2-24% for fibrous mixtures. The best results of highest strength increment or lowest decrement were obtained for WG replacement ratios of 30 and 60%. The dual action of WG and the low-cost PVA fibers reduced the gain or increased the loss in the mechanical properties. Finally, considering all obtained results, it can be concluded that the positive effects of WG surpass its negative effects.