Flexural behavior of reinforced concrete slabs containing recycled glass powder and steel fibers

Abstract

Because of the massive environmentally unsustainable output from industrialization, concrete can benefit from using glass powder (GP) as a cement replacement to achieve sustainability. This research addresses the experimental results for seven reinforced concrete (RC) slabs containing recycled GP and steel fibers (SF) under flexure. The experimental variables are the replacement ratios of GP by cement weight (0 %, 10 %, and 20 %), the addition of SF (0 %, 0.5 %, and 1 %), slab thickness (100 mm and 120 mm), and the ratio of longitudinal reinforcement (0.61 % and 0.86 %). The load–deflection curves, load-steel strain relationships, stiffness, ductility, and toughness are plotted and calculated. Test results showed that the compressive and splitting strengths of concrete mixes containing 10 % GP at 28 days increased by 4.7 % and 1.7 %, respectively, compared to the conventional concrete. For the case of the 20 % addition of GP, the compressive and splitting strengths decreased by 10.7 % and 5.9 %, respectively compared to the conventional concrete. Experimental results indicated that utilizing GP as a substitute for cement by 10 % and 20 % shows an acceptable performance of RC slabs and 10 % GP is the optimum replacement ratio that is suitable for use in concrete mixes. Slabs containing 10 % GP indicated an increase in the failure loads by 8.8 % and that has 20 % GP indicated insignificant reductions in the failure and crack loads by 14.7 % and 5.9 % respectively. The addition of SF to concrete containing GP improved the performance, toughness, and stiffness of RC slabs. Finally, a comparison between the results of the experiment and the provisions of different design codes was performed and a good agreement has been reported. The average value between the predicted and experimental load capacities was 0.99 with a standard deviation of 0.10.