Shear and flexural performance of reinforced geopolymer concrete beams cured under ambient and oven conditions with environmentally friendly waste steel tire wire additives

Abstract

Abstract In this study, the effects of Granulated Blast Furnace Slag (GBFS) and Waste Steel Wire (WSW) admixtures on the flexural and shear performances of Reinforced Geopolymer Concrete Beams cured under oven and ambient conditions were investigated experimentally and analytically in detail. The research used 100 mm and 270 mm stirrup spacings and changed GBFS and WSW with 0%, 10%, 20%, and 1%, 2%, and 3%, respectively. To evaluate flexural and shear strength of reinforced GPC, 100 × 150 × 1000 mm samples were made. The results showed how material proportions affect flexural, and shear beam mechanical performance and ductility. In flexural beams, increasing the GBFS ratio to 10% enhanced load bearing capability and preserved ductility. However, 20% of GBFS reduced load bearing capability and brittle fractures. It was found that mixtures with GBFS of 10% and WSW of 3% are optimum for flexural beams. For shear beams, brittle fracture was observed for all GBFS and WSW ratios and ductile behavior was not achieved. Increasing GBFS content to 10% boosted capacity from 2.05 to 19.37%, however increasing it to 20% dropped capacity from 2.72 to 15.10%. Increasing WSW content enhanced load bearing capability, however increasing GBFS content over 10% did not. It is emphasized that different materials and design methods should be investigated to ensure ductile behavior in shear beams. Increasing the WSW ratio from 0 to 3% boosted energy consumption capacity by 2.78 times. But raising the GBFS ratio to 20% reduced energy consumption capacity by 66%. In addition, AS3600 predicted beam damage more correctly in different conventional computations. This study shows that the GBFS ratio should be limited to 10% and the WSW ratio to 3%. This combination maintains ductility in flexural beams and gives a safe design limit in shear beams while increasing load bearing capability. The results obtained provide important information that will shed light on new designs.

Keywords

• Waste steel wires
• Reinforced concrete beam
• Flexural
• Shear
• Oven
• Ambient