Engineering properties of reinforced geopolymer concrete beam produced from recycled aggregate

The utilization of recycled materials in the concrete industry has become one of the most essential environmental needs today, and more technical and economic studies are being performed every day in this subject. The effect of recycled materials on the shear behavior of geopolymer concretes was investigated in this work, along with a comparison to conventional recycled concretes and the effect of recycled aggregates on both concrete groups. For this purpose, ten mixing designs with recycled aggregate replacement percentages of 0, 25, 50, 75, and 100 were made in two groups of ordinary concrete and geopolymer concrete, as well as mechanical tests such as compressive strength, modulus of elasticity, and pull-off test. A reinforced beam without a shear element was also created for each mixing design to study the effect of this type of aggregate on the shear behavior of the beam. The findings revealed that increasing the percentage of recycled aggregates causes a loss in mechanical characteristics in the designs and a reduction in beam bearing capacity, indicating that geopolymer concrete has a higher replacement capacity than regular concrete.