RESEARCH ON THE IMPROVEMENT OF SULFURIC ACID RESISTANCE BY VARIOUS MORTAR PREPARATION IN CONSIDERATION OF ENVIRONMENTAL LOAD REDUCTION

Abstract

This study aimed to develop a precast concrete mix which is excellent in sulfuric acid resistance. The experimental factors were the type of binder and aggregate, the combination of materials, the substitution ratio of admixture, the ratio of sand binder to the ratio of water binder, and the sulfuric acid immersion test was performed with a mortar specimen. As a result, the influence of the fine aggregate on the sulfuric acid resistance was larger than that of the binder, and the waste molten slag, limestone crushed sand and blast furnace slag fine aggregate suppress the permeation of sulfuric acid to the inside. In addition, the influence of the water binder ratio on the sulfuric acid resistance is that in the use of washed sea sand and limestone crushed sand in the fine aggregate, as the water binder ratio is smaller, the surface layer part peels off and the penetration of sulfuric acid into the inside progresses. In the blast furnace slag fine aggregate use formulation, a dense film was formed on the surface layer, and the penetration of sulfuric acid into the interior was suppressed as the water-bonding material ratio was smaller.