An experimental investigation of sustainable self-compacting concrete with expired cement cold bonded fly ash lightweight aggregate on strength and permeability

In this research, expired cement cold-bonded fly ash lightweight aggregates(ECFLA), silica fume (SF) and fly ash(FA) were incorporated into self-compacting concrete (SCC) as eco-friendly replacements for self-consolidating lightweight concrete (SCLC). A tilted pan was used to make ECFLA by cold bonding EC and fly ash 20% and 80%, respectively. In the control group, partial and complete ECFLA mixed aggregates substituted natural coarse aggregates at 0%, 50%, and 100% reference self-compaction concrete SCC, FA was replaced with cement to a binary blend at 20% in the second group. The third group used a binary blend of Portland cement and 10% fixed SF, whereas the fourth group used a ternary blend of the same admixtures. The study examined compressive strength, ultrasonic pulse velocity, splitting tensile strength, water absorption, permeability test, and sorptivity test, at 28 and 90 days curing ages. SCC with ECFLA has harmful mechanical characteristics and higher permeability. Mineral admixtures significantly improved the permeability of SCLC. The compressive strength was reduced by approximately 16.3% and 23.3% respectively, by 50% and 100% ECFLA substitution at 28 days. The SF is the most important mineral admixture factor, with improvements in compressive, splitting, and flexural strengths of 29%, 10.8%, and 14.4%, respectively.