Simultaneous effects of microsilica and nanosilica on self-consolidating concrete in a sulfuric acid medium

Abstract

Combination of microsilica and nanosilica (colloidal silica) are considered to design a high strength self-consolidating concrete to resist in the sulfuric acid medium. Artificial intelligence was used to predict and compare the behavior of these two pozzolans in a sulfuric acid medium. Contour plots were used to investigate the products combination better. Thermogravimetric analysis (TGA) was also used to find the calcium hydroxide range while using these two pozzolans. TGA revealed that colloidal silica did not contribute to cement hydration within seven days of curing while a combination of them boosted calcium hydroxide consumption. The results show that more substitution of the pozzolans could lead to lower mass loss while nanosilica has marginal effect on the residual compressive strength. The results also revealed that 7 percent substitution of microsilica showed the same effect as 2 percent nanosilica replacement. © 2017 Elsevier Ltd