| 摘要 |
PURPOSE:To reduce an amount of dust, splashing of concrete, peeling, etc., in spraying concrete by using a concrete spraying machine by adding a dust inhibitor and fumed silica to a concrete materials for spraying. CONSTITUTION:Concrete materials of an aggregate and cement, etc., are fed to a mixer M at a concrete producing plant, stirred, mixed with fumed silica, stirred, further blended with a dust inhibitor and then with water and agitated. Then the prepared concrete for spraying is transported to a concrete spraying machine 2 at an operation field by a truck mixer agitator 1. Then the concrete for spraying is fed from the truck mixer agitator 1 to a concrete spraying device 2, sent under pressure to a nozzle 6 by compressed air and sprayed to wall face of tunnel, etc. Methyl cellulose, etc., are used as the dust inhibitor. |
