WET SPRAYING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a spraying method by which the amount of powder dust generated upon spraying of the concrete is reduced by using a base concrete and a spray device used in a general wet spraying method. SOLUTION: A set accelerating agent to be used, a total volume of force-fed air, a position of confluence and mixture of the quick-setting agent and the concrete, and the base concrete to be used are set to be specific, respectively. Namely, according to the wet spraying method, the following conditions (a) to (d) are met. (a) The volume of press-fed air for confluence and mixture is 3 to 10 m3/min. (b) The quick-setting agent is composed of 30 mass% or less of particle content of which the particle size is 7μm or less. (c) The base concrete is the concrete having a slump of 10 cm or more. (d) The distance from the position of the confluence and mixture of the quick-setting agent and the base concrete to a cylinder front of the spray nozzle is 0.5 to 3 m. The quick-setting agent is preferably composed of agglomerated particles made by agglomerating the particles having the particle size of 7μm or less. The base concrete preferably includes a specific water-soluble high polymer compound. COPYRIGHT: (C)2006,JPO&NCIPI