When it blows the primary covering works barrel

摘要

PPROBLEM TO BE SOLVED: To overcome the difficulty of accuracy improvement during spraying of concrete according to a conventional concrete spraying method which is carried out depending only on laser, and to provide a new method of placing tunnel lining concrete, which is implemented by a facility that can be taken in a working face when the concrete is sprayed and taken out after completion of the spraying, repeatedly usable, simple in structure, and easy to set. PSOLUTION: When a concrete layer as primary lining is sprayed to a tunnel inner wall by a spraying machine 7 with an erector 8, an arched gauge 10 is built up by the erector 8, and the concrete is sprayed by using the arched gauge 10 as a guide. The arched gauge 10 is formed of steel pipes. To build up the arched gauge 10, firstly a building location is marked by laser irradiation, and then the arched gauge 10 is built up by following the marking. PCOPYRIGHT: (C)2007,JPO&INPIT