IMPROVEMENT IN FIRE RESISTANCE PERFORMANCE OF HARDENED MATERIAL OF HYDRAULIC BINDER

摘要

PROBLEM TO BE SOLVED: To remarkably improve the hardening performances of a hydraulic binder by kneading and hydrating a hardened material of a cement-based hydraulic binder so as to provide the composition of the hardened material of the cement-based hydraulic binder and the ratio of the water to the binder within specific ranges. SOLUTION: A hardened material of a cement-based hydraulic binder is kneaded and hydrated and the ratio of water to the binder thereof is 15-40wt.% to produce ettringite (3CaO.A12 O3 .2CaOSO4 .32H20) and/or an iron type ettringite (3CaO.Fe2 O3 .3CaSO4 .32H2 O). Thereby, fire resistance performances of the hardened material of the hydraulic binder are improved. Preventing effects on explosion possessed by the ettringite are manifested according to this method and the explosion can completely be prevented while maintaining the strength as a high-strength concrete. Since sharp-cornered grains possessed by a slag or gypsum especially form fine voids in the hardened material, a rise in pressure is suppressed in dehydration to prevent the explosion.