QUICK SETTING AGENT FOR SPRAYING, SPRAYING MATERIAL, AND SPRAY CONSTRUCTION METHOD USING THE SAME

PROBLEM TO BE SOLVED: To provide a quick setting agent for spraying which is excellent in quick-setting and strength developability even if the amount of an alkali used is small, compared with a conventional quick setting agent, and to provide a spraying material.SOLUTION: The quick setting agent for spraying contains 100 pts.mass of an amorphous calcium aluminate, 50-150 pts.mass of an anhydrous gypsum, 1-5 pts.mass of a powdered alkali metal aluminate having an RO/AlOmolar ratio (R is an alkali metal) of 0.8-1.2, 10-20 pts.mass of a powdered aluminum sulfate, and 0.2-1 pts.mass of a hydroxy carboxylic acid, wherein RO in the quick setting agent is 1% or less. The spraying material contains 7-15 pts.mass of the quick setting agent for spraying based on 100 pts.mass of cement; and cement concrete. A spray construction method includes joining and mixing the quick setting agent for spraying with cement concrete at the tip of a discharge port; and blowing the mixture.