| 摘要 |
PROBLEM TO BE SOLVED: To avoid excessive design of a coating layer formed by spraying. SOLUTION: A spraying device is provided with a fine powder feeder 10, a flash-setting agent feeder 12 and a spraying pipe 14. A main component A, an oxidizer C and a hardening accelerator D are sent from the feeder 10 to the pipe 14, conveyed toward the tip side of the pipe 14 and mixed with an adhesive component in the vicinity of nozzle 23 to produce a flash-setting compsn. In a process for hardening the compsn., the main component A becomes the nucleus of a hardened body. In a formed coating layer, polytacrylate salt or polymethacrylate salt is interposed among dispersed active fine particles to become a form where the active fine particles are stuck by these materials. After the formation of the coating layer, the main component A consisting of blast furnace slag and fly ash produces a hardened body. The hardening accelerator D accelerates the hardening of the main component A and the strength of the coating layer can be regulated in accordance with the added amt. of the accelerator D. After about 2N/mm<2> compressive strength is exhibited at 10 min of age, the strength can be increased up to about several times for long term. |
