| abstract |
(57) [Problem] To provide a quick-setting agent, a cement composition, a spraying material, and a spraying method using the same, which can suppress an alkali aggregate reaction. SOLUTION: A quick-setting agent comprising calcium aluminate and anhydrous aluminum sulfate. A quick setting agent comprising calcium aluminate, aluminum sulfate, and 0.01 to 5 parts by weight of an alkaline substance based on 100 parts by weight of calcium aluminate and aluminum sulfate in total. |