Flexural behavior of reinforced high strength concrete slabs containing glass powder, flay ash, and rice husk ash as cement substitute

Abstract

This study supports a move toward greener construction methods by endorsing sustainable building materials, which can have long-term positive effects on the environment and public health. Utilizing waste materials makes concrete production more environmentally friendly by lowering emissions, landfill usage, and the need for natural resources. The purpose of this study is to evaluate the effect of using glass powder (GP), fly ash (FA), and rice husk ash (RHA) as cement substitutes on the flexural behavior of reinforced high-strength concrete (RHSC) slabs. Ten RHSC slabs with different proportions (0 %, 10 %, 15 %, and 20 %) of GP, FA, and RHA as cement substitutes were experimentally cast and tested under four-line loading conditions. Experimental results indicated that using FA and RHA as cement alternatives for HSC mixes reduced workability, whereas GP increased it. Test results showed that the HSC mixes containing 15 % GP, 15 % FA, and 10 % RHA had the highest increase in compressive, tensile, and flexural strengths. Incorporating 15 % GP, FA, or RHA enhanced the ultimate load, stiffness, and toughness of the tested RHSC slabs compared to the control slab. Conversely, increasing replacement levels of GP, FA, or RHA to 20 % of cement led to a reduction in ultimate load. The optimal replacement ratios for the RHSC slab are 15 % GP, 15 % FA, or 10 % RHA, which result in acceptable performance of RHSC slabs and protect the environment and natural resources. Finally, the predictions of two methodologies, ACI 318 and ECP 203, were compared with the experimental findings, revealing satisfactory concordance.