Improving the Mechanical and Durability Performance of No-Cement Self-Compacting Concrete by Fly Ash

Abstract

The eco-binder with optimized fractions of ternary solid waste materials of ground granulated blast furnace slag (GBFS/slag), class F fly ash (FFA), and circulating fluidized bed combustion (CFBC) fly ash was successfully used to manufacture no-cement self-compacting/self-consolidating concrete (NC-SCC). In the current study, the enhancement of mechanical and durability properties of NC-SCC with FFA was evaluated using the experimental testing of compressive strength, water absorption, sorptivity, dynamic elastic properties, and ultrasonic pulse velocity. Experimental results showed that addition of FFA at 30 wt% as partial replacement of slag was considered as the optimum value to produce the NC-SCC with the highest mechanical properties including compressive strength, dynamic moduli, and superior durability properties due to the lowest water absorption and volume of permeable voids computed from the test on initial and secondary rate of capillary absorption. Microstructural performance detected by using scanning electron microscopy (SEM) obviously supported that the structure of interfacial transition zone between binder and aggregate of the NC-SCC with optimized FFA addition seemed to be strengthened by the extra hydration products contributed to the FFA particles.