Effect of waste glass powder as partial replacement of cement & sand in concrete

The use of waste materials in concrete is now a global trend for effective waste management in order to create a sustainable, eco-friendly concrete. This has the added benefits of protecting natural resources by means of producing more sustainable concrete that has better mechanical properties. This study investigates the characteristics of concrete that contains waste glass powder (WGP) as partial replacement of cement and sand. Laboratory tests were performed to determine the compressive strength and split tensile strength of concrete with 0%, 5%, 10%, 15% and 20% partial replacement of cement and sand separately by WGP after 7, 28, 60 and 90 days of moist curing. Microstructural investigations of X-ray diffractometry (XRD) and scanning electron microscopy (SEM) were performed to determine the effect of WGP on the microstructure of concrete. Results has shown that compressive strength of concrete can be improved to a considerable value at 7, 28, 60 and 90 days when WGP is used as partial replacement of cement by 5%, 10% and 15%, which can be considered as a reasonable amount in producing sustainable concrete. Further replacement percentages resulted in a decrease in compressive strength. WGP enhances the microstructure of concrete in the term of pozzolanic activity and decreasing the microcracks.