Mechanical properties of sustainable concrete made with ceramic and sandcrete block wastes

Material reuse has become one of the most active areas of research being investigated by various researchers. The amount of waste produced and the rate at which naturally occurring resources are being depleted is becoming alarming. As a result, researchers have been looking into viable methods of reusing these wastes, directly reducing the rate at which our limited natural resources are consumed. This study presents the findings on an experimental investigation of the partial replacement of natural fine aggregate (NFA), ordinary Portland cement (OPC) with recycled fine ceramic (RFC), and calcined granulated ceramic (CGC); and the complete replacement of the NFA with recycled fine aggregate (RFA) from the crushed sandcrete block and partially replaced it with RFC. The aggregates were replaced from 10% to 50% in step of 10%, while the cement was replaced from 5% to 25% in step of 5%. A mix ratio of 1:2:4 by weight was used with a w/c ratio of 0.55, and the compressive strength of the concretes produced using a cube size of 150 × 150 × 150 mm was carried out after being cured 7, 14, 28, and 56 days. The result showed that the workability of the concrete decreases as the percentage replacement increases. However, there was an increase in the compressive strength for the partial replacement of NFA as the replacement increased. A decrease in strength, at 40% and 50% replacement was observed. Similarly, the compressive strength decreases with an increase in replacement of OPC with CGC, and the highest decrease occurred at 25%, while the slightest drop was at 5%, which resulted in 27.87% to 33.60% and 4.18% to 5.17% decrease in strength respectively at 28 and 56 days. In addition, complete replacement of NFA with RFA and partially replaced with RFC resulted in a decrease in strength. It was observed that the highest reduction in strength was at 50% replacement resulting in a 24.85% and 24.91% decrease in strength at 28 days and 56 days, respectively. The use of recycled sanitary ceramics (RSC) and recycled sandcrete block (RSB) wastes would help get them used in concrete and other construction materials, but it would also help reduce landfill space and protect the environment from potential pollution impacts.