Cleaner Materials (Sep 2022)
High and normal strength concrete using grounded vitrified clay pipe (GVCP)
Abstract
Several challenges faced the carbon footprint reduction of concrete production. Recycling waste materials from different industries to produce green concrete would be a proper solution due to their low cost and space-saving for landfill purposes. One of these industries is manufacturing vitrified clay pipes used for sewage, which show high resistance to the aggressive environment. However, vastly deteriorated pipes are disposed of as waste in landfills while processing. Additionally, the vitrified clay pipes are sourced from the kaolin burnt at a temperature above 800 °C while processing; no literature introduces the disposal wastes as supplementary cementitious material (SCMs). Nevertheless, other wastes such as ceramic sourced by metakaolin were introduced. This paper studies the grounded vitrified clay pipe (GVCP) as SCMs for producing green concrete. The methodology encountered examining the durability and mechanical properties of concrete using GVCP. Two group sets suggested; normal and high concrete strength with 0, 5, 10, 15, 20, and 25% cement replacement by GVCP. Slump, compressive and flexural strengths, and abrasion were assessed while microstructure analysis handled. The results showed that the optimized values would be 10% and 20% for normal and high concrete strength in which mechanical properties are provided. The study also suggested a coefficient of 1.52 and 0.7 for ACI 318 and EN 1992-1 flexural provision. The GVCP showed higher resistance to chloride ingress of fewer than 1000 coulombs even at a high water-to-cement ratio of 0.64. The X-ray diffraction (XRD) revealed that GVCP provided more CSH gels, increasing compressive strength at later ages.