Experimental study on the reuse of cathode ray tubes funnel glass as fine aggregate for developing an ecological self-compacting mortar incorporating metakaolin

Industrial waste causes a lot of pollution, particularly electrical and electronic waste (WEEE) such as glass cathode ray tubes (CRT) which create environmental pollution and health hazards. The field of civil engineering, like sectors in the world has leaned towards sustainable development by emphasizing environmental aspects as an important goal. This strategy is achieved by recycling and reusing polluted industrial sites, materials, waste, by-products or industrial residues. In this paper a study was carried out to explore the use of recycling waste glass obtained from crushed CRT as fine aggregate, and metakaolin (MK), as a partial replacement of Ordinary Portland cement (OPC) for the development of eco-self-compacting mortar (SCM). Here, OPC is replaced by 5, 10, and 15% of MK by weight, and fine aggregate is replaced by 0, 10, 20, 30, 40 and 50% of CRT by weight. The mini-slump flow and V-funnel flow time of fresh SCM are evaluated. The compressive strength, flexural strength, water absorption, resistance to high temperature, porosity and microstructure of hardened SCM are also performed. These experiments indicate that using CRT glass with MK increases the flowability of SCM and reduces the dosage of superplasticizer (SP). The incorporation of 10% MK with CRT mixture showed higher mechanical properties, lower porosity and dense structure. Moreover, the water absorption and resistance to high temperature have been improved by 10% and 15% of the MK group respectively, for all SCM made with CRT glass. This combination of MK and CRT glass as a fine aggregate in SCM is a low-cost ecosystem for a much cleaner environment.