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Many high-performance concrete (HPC) applications are often supported by additional cementitious materials for mechanical properties such as strength and performance. This research works to determine the possibility of using the waste glass powder (WGP) obtained by grinding crushed ground waste glass bottles to partially replace silica fume (SF) in HPC. 10%, 20%, and 25% replacement, which comprised the same water-to-binder ratio and workability conditions, were verified. After being subjected to 750 °C for 2 h, the experimental program was developed and evaluated with regard to compressive strength, flexural strength, and residual compressive strength, which resulted in the best measured compressive strength of SF mixtures occurring with 10% replacement, reaching 108 MPa at 28 days, and higher values obtained with 20% replacement in WGP mixtures from 113.2 MPa. There is no large variation of flexural strength between the tested mixtures except for the highest measured value of 8.4 MPa at WGP at 20%. The residual compressive strengths in WGP mixtures before and after being exposed to high temperatures were higher than in their respective SF mixtures under the laboratory conditions. These findings indicate that the WGP is a potential alternative supplementary cementitious material in HPC in the examined replacement range. However, this performance should be taken to provide a comparative evaluation within the tested program, and additional microstructural studies are needed to confirm the proposed mechanism of increased heat.

This study attempts to apply the concept of sustainability by reducing the environmental pollution of plastic waste, especially Polyethylene Terephthalate (PET) that are used in production soft drinks bottles. The plastic bottles were collected, roughened) Roughen the surface by using a metal clip after exposing it to heat, and then place it on smooth surfaces) and shredded into fibres of specific size and shape with an aspect ratio (L/D) of 34.5. Various proportions of PET (i.e. 0.5, 1.0, and 1.5%) have been used in the production of ordinary concrete. The influence of PET fibers on the properties of concrete was studied, such as workability, compressive and splitting tensile strengths. Furthermore, the shear characteristics of continuous reinforced concrete deep beams with dimensions of (150×300×2000) mm produced from such concrete were also investigated. For all percentage of replacements, The fresh property, compressive strength, and tensile strength of PET fibre encapsulated cement concrete were investigated. With the addition of plastic fibre, compressive strength increased marginally, but tensile strength measurements showed a substantial improvement over the control specimen.it has been found that there was an apparent impact of waste plastic fibers on the structural behavior of the investigated beams in terms of its brittleness. The increase in the ultimate load capacity With the increase in the percentage of fiber until a percentage(1%), then it begins to decrease after this percentage of continuous deep beams refers to the use of waste plastic fibers to improve the tensile properties of concrete and to limit the spread and width of cracks within the structure.

This study attempts to put sustainability into practice by minimising the pollution caused by plastic trash, particularly polyethylene terephthalate (PET), used in the production of soft drink bottles. To achieve this, experimental work was conducted to investigate how the incorporation of waste PET fiber affected the shear behaviour of eight reinforced concrete continuous deep beams with dimensions 150 × 300 × 2000 mm. Four samples were tested until failure without CFRP strengthening to highlight the effect of PET fiber; these have incorporated waste plastic fiber (PET) with an aspect ratio (L/D) of 34.5 at varying percentages (0.5%, 1%, and 1.5%) of the concrete mix volume. The four remaining samples were loaded to 60% of their designed loads and then strengthened with carbon fiber reinforced polymer (CFRP) using a 90° wrapping scheme before being tested for shear performance. The results showed the presence of discarded plastic fiber had a clear influence on the structural behaviour of the samples, with the highest increase in shear strength recorded for the sample with a fiber ratio of 1% for both non-strengthened and CFRP-strip strengthened samples. The results also confirmed that the CFRP strengthening scheme provides higher cracking load, higher ductility, and stiffer samples as compared with no reinforcement. The waste plastic fiber improved the concrete tensile strength and prevented crack propagation within the structure, and CFRP wrapping converted failure from shear to bending failure in all cases, however.

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