Effects of sulfate rich solid waste activator on engineering properties and durability of modified high volume fly ash cement based SCC

The engineering properties and durability of high volume low calcium fly ash (HVFA) cement based self-compacting concrete (SCC) modified with addition of circulating fluidized bed combustion (CFBC) fly ash were explored. Experimental results showed that an addition of CFBC fly ash did not influence the stability and passing and filling abilities of modified HVFA cement based SCCs. But its presence significantly improved the compressive strength, bonding behavior, and durability of the hardened SCC specimens. The added small amount of CFBC fly ash was found to increase the earlier compressive strength of hardened SCC specimen at one day of curing up to 43.8% higher than that of the control SCC specimen, which indicates a remarkable contribution of CFBC fly ash addition to shortening the time of construction. At ages of 3, 7, and 28 days, such increases were up to 30.2%, 22.3%, and 17.8%, respectively.