| 摘要 |
PROBLEM TO BE SOLVED: To provide a fire resistant coating material for protecting a steel frame structure from combustion heat at fire, having a reduced coating thickness for developing predetermined fire resisting performance. SOLUTION: The fire resistant coating material containing KAl(SO<SB>4</SB>)<SB>2</SB>12H<SB>2</SB>O and H<SB>3</SB>BO<SB>3</SB>is mixed with water as kneading water at a construction site. A mortar pump as a forcible feeder is used for giving spray work of coating thickness 5 mm to the outer surface of an angular steel pipe of 300×300×9 mm as the steel frame structure. After work, the fire resistant coating material is generally hardened with the hydration of Portland cement to obtain the steel frame structure with a fire resistant coating. When exposed to combustion heat at fire, the steel frame structure has temperature rise. At the stage that the temperature of the steel frame structure reaches about 100°C, KAl(SO<SB>4</SB>)<SB>2</SB>12H<SB>2</SB>O crystal water is desorped from the composition of the fire resistant coating material to generate endothermic reaction which suppresses the temperature rise. It is followed by H<SB>3</SB>BO<SB>3</SB>dissolved in the desorped crystal water to generate endothermic reaction which further suppresses the temperature rise. COPYRIGHT: (C)2005,JPO&NCIPI
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