| abstract |
(57) [Summary] [PROBLEMS] A rebound reducing agent which can reduce the rebound rate and the amount of dust and can be economically constructed, a spray material thereof, And to provide a spraying method using the same. SOLUTION: A rebound reducing agent containing an alginate and a polyacrylate, an alginate and a polyacrylamide, a rebound reducing agent containing a polyacrylate, a quick-setting agent and a blowing agent containing the rebound reducing agent A cementing composition containing a cementing material, cement and the spraying material, and a spraying method in which cement and a quick-setting concrete containing a quick-setting agent and the rebound reducing agent are mixed and sprayed at a spraying nozzle portion. Configuration. |