Verification of Mechanism on Improvement of Drying Shrinkage or Air Permeability on Concrete Using Blast Furnace Slag Sand Based on Pore Structure
In this study, the differences in the pore structures densified by the blast furnace slag (BFS) sand and powder were investigated by using the mercury intrusion test and removing the fine particles contained in the sand. By using BFS sand, the pores with a diameter of 400 nm or higher were densified. The characteristics of the transition zone detected in natural sand were not observed with the elemental analysis around the BFS sand. A strong correlation was found between the volume of the pores densified by mercury intrusion method and drying shrinkage and the air permeability coefficient. It was verified that the densification and adhesion strengthening of cement paste and sand by BFS sand improve the drying shrinkage and air permeation resistance. Using BFS sand, concrete infrastructures can be more durable.