Utilization of Waste Glass in Autoclaved Aerated Concrete

Abstract

This experimental study aimed to design an autoclaved aerated concrete (AAC) with different kind of glass wastes as an alternative fine aggregates for mass housing projects that will meet the requirements in order to help contribute to the industry in saving the environment. Moreover we want to encourage the government to find solutions regarding the disposal to landfills of glassy waste materials and provide new knowledge to the contractors and developers on how to improve the construction industry methods and services by using glassy waste to sustain good product performance and meet recycling goals. Different kinds of glass wastes in the form of sub grain packaging glass cullet, CRT (Cathode Ray Tube) panel glass waste and calsi glass, were used as a sand replacement in AAC production. Large proportion of the post-consumer glass is recycled into the packaging stream again, but some sub grain packaging glass cullet does not meet the strict criteria for packaging glass thus is sent to landfill. CRT is classified as a hazardous glass waste and there are several issues surround CRTs which create barriers to increased recovery of the glass. In countries e.g. Latin America and Asia where still CRT glass is being produced even when shredder, the glass stream is a mixture of panel and funnel glass, making it difficult for reuse in new CRTs. Based on our knowledge also calsi glass as a processed blast furnace slag is not used in packaging production. The viability of current and novel applications of mentioned glasses is examined here. Although aerated concrete was initially envisaged as a good insulation material, there has been renewed interest in its structural characteristics in view of its lighter weight, savings in material and potential for large scale utilization of wastes. Due to this fact we undertake the studies of an influence of different amounts of glass wastes onto properties of aerated concrete in terms of physical (microstructure, density), mechanical (compressive and tensile strengths) and chemical characteristic. Use of milled waste glass in concrete as partial re-placement of sand represents an important step towards development of sustainable (environmentally friendly, energy-efficient and economic concrete-based infrastructure systems.