الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Recycling waste materials instead of using traditional construction materials in civil infrastructure and buildings is a significant step toward reducing greenhouse gas emissions and the consumption of natural resources. The scope of this thesis is to identify the properties of sustainable concrete where waste materials such as rubber tires, crushed clay bricks, and crushed glass can be utilized to replace the fine or coarse natural aggregate with substitution percentages of 25, 50, and 100% by volume. Slump, compressive strength, elastic modulus, impact resistance, density, and sorptivity tests were performed. In addition, scanning electron microscopy (SEM) and X–ray diffraction (XRD) were studied to determine the microstructure properties of concrete. The rubberized concrete mixes showed worse workability due to their irregular surface texture. While crushed glass concrete showed good workability due to its smooth surface, crushed clay brick showed good workability because it was used in saturated surface dry that meant additional water added to the mix. The decrease in dry density was 55% less than the control mix when rubber aggregate was used, while it reached 17% and 4% when crushed clay brick and crushed glass aggregate were used, respectively. The sorptivity of sustainable concrete increased when the amount of waste increased, and its value ranged from 2.7 x 10-3 to 16.5 x 10-3 mm/s½ compared to the control mix, whose value was 2 x 10-3 mm/s½. The lowest sorptivity in sustainable concrete was found in coarse rubberized concrete that ranged between 2.7 and 4.5 mm/s½ due to rubber tire blocking the pathway of water. The compression strength and elastic modulus decreased as waste content increased, except for the fine glass mix. The compression strength of the fine glass mixture was 5.58% greater than that of the control mixture, while the elastic modulus of the fine glass mixture was higher than the control by 2%. The reason for this behavior was attributed to glass powder particles that fill the porosity between coarse aggregates and high viscosity of glass powder mix. The high viscosity obtained in glass powder mixes was attributed to the high slump, and no segregation occurred. When mixing, the viscosity creates a good suspension of coarse aggregate, which can reduce inter-particle interaction and grain gathering. As a result, it increases the mortar’s capacity to fill formwork, strengthens the adhesion between the mortar and coarse aggregate, and lowers the risk of segregation. Additionally, the compression strength of treated rubberized concrete using NaOH was higher than that of untreated one by 31%. The findings of this thesis demonstrated that the studied waste materials can be used to produce either sustainable lightweight concrete without severe deterioration of mechanical properties or conventional concrete with better mechanical performance.