Investigation of the Use of Locally Generated Waste Glass as Substitute of Natural Sand in Concrete Production

Sustainability and environmental considerations are now a prerequisite for the construction industry. Several approaches could be adapted to embrace the sustainability concept and contribute in reducing the environmental impact of construction sector, especially concrete production. Large variety of waste, recycled and byproducts materials are now being used in cement-based materials as a secondary material in a partial or even a full replacement of natural non-renewable materials. Glass is well known as a non-biodegradable material. Waste glass if not collected, screened, washed and properly recycled could severely affect the environment and the quality our of life. In developed countries, efficient glass recovery and recycling systems are well implemented and managed to avoid waste glass ending up in landfilling and its numerous disastrous environmental effects. Yet no effective glass recycling system is established in Oman and many other developing countries which lead to huge amount of waste glass land filled and thrown out in the ground. This causes a considerable economic lose and severe environmental implications. In addition, many types of waste glass are unsuitable for recycling into secondary product/markets. Concrete and cement-based materials offer a unique and exciting possibility to valorize this type of waste materials in concrete when properly designed. Waste glass that is screened and crushed is strong, safe and economic when used as a sand substitute in concrete production. Extensive experimental work carried out using up to 100% of waste flat window glass as partial?full replacement of natural sand showed a great potential of glass concrete that combines acceptable mechanical properties with environmental benefits.