الفهرس 
CHAPTER 1 : INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Although concrete is a widely used construction material, its production through the cement industry causes negative effects on the environment, such as contributing to global warming due to carbon dioxide emissions. To tackle this issue, researchers are focusing on developing sustainable structures using ”green concrete”. One type of green concrete, called geopolymer concrete, uses industrial waste materials to replace ordinary Portland cement (OPC), which helps reduce pollution by utilizing by-products from industry and mitigates carbon dioxide emissions by eliminating OPC production. In buildings where there is limited clear floor height, it is important to have openings in reinforced concrete (RC) beams to allow various services to pass through. Therefore, this study examines the behavior of geopolymer concrete beams with web openings by conducting four-point loading tests. The experimental program consisted of 26 beams that had dimensions of 100×250×2000 mm. These beams were divided into five main groups with different specifications. The first group comprised of two control beams, one of which was made of conventional concrete while the other was made of geopolymer concrete. The second and third groups consisted of six beams each, with openings at mid-span and side-span, respectively, made of conventional concrete. The fourth and fifth groups had test beams identical to those in the second and third groups, except that they were made of geopolymer concrete. All four groups had three different opening sizes: small (125×125 mm), medium (125×250 mm), and large (125×375 mm). Geopolymer concrete beams exhibited comparable performance to conventional concrete beams with slightly lower ductility, especially under shear stresses. Overall, the results of the experiments indicate that geopolymer concrete may be a feasible alternative to OPC in certain types of beams in the foreseeable future. Nonetheless, a cost-benefit analysis revealed that the initial costs of geopolymer concrete are 48% higher than that of conventional concrete. Additionally, additional research is necessary to fully comprehend geopolymer concrete’s behavior. Test specimens were simulated using ABAQUS, a nonlinear finite element analysis tool. This analysis accounts for stress-strain relationships, tension-stiffening effects, cracking, and crushing. The results of the analysis showed good agreement with the experimental test results.