Study on Influences of Slag Powder and Fly Ash on Concrete Penetration Performance

Abstract

The resistance to chloride ion penetration of the concrete added with slag powder and fly ash is studied in this paper. The tests show that: adding slag powder and fly ash to concrete can improve the concrete’s resistance to chloride ion penetration; if only adding slag powder, the larger the adding content and the longer the test age, the better the concrete’s resistance to chloride ion penetration; if only adding fly ash, the longer the test age, the better the concrete’s resistance to chloride ion penetration; at the age of 28, 56 days, if the fly ash adding content is 30%, the concrete’s resistance to chloride ion penetration is optimal, while at the age of 84 days, if the fly ash adding content is 40%, the concrete’s resistance to chloride ion penetration is optimal; if adding both slag power and fly ash, the larger the adding content and the longer the test age, the better the concrete’s resistance to chloride ion penetration; if the test age and adding content remain constant, for the concrete’s resistance to chloride ion penetration, it is the best when adding both slag power and fly ash, it is good when adding only slag power, and it is poor when adding only fly ash; for the influences of the test age on the concrete’s resistance to chloride ion penetration, it is maximum when adding only fly ash, it is moderate when adding both slag powder and fly ash, and it is minimum when adding only slag power; and the larger the adding content, the greater the influences of the test age on the concrete’s resistance to chloride ion penetration.

Durability Performance of Reinforced Concrete-Based Fly Ash Exposed to Combined Chloride-Sulfate Attack

“…This is confirmed by the improvement of the Rp of M2 by approximately 82% in the aggressive exposure compared to the neutral environment, while for the reference concrete M1 the Rp resistance is dropped by roughly 91%. This high level of resistance of M2 containing FA can be attributed to the matrix densification which reduces the pore connectivity, thus reducing the permeation of chloride ions [14][15][16]. The diffusion of chloride ions in concrete, which causes steel corrosion, is primarily influenced by permeability [17].…”