EXCAVATOR SHAFT AND CONSTRUCTION METHOD THEREOF

PROBLEM TO BE SOLVED: To provide an excavator shaft for allowing easy pull-up of a core material, and a construction method thereof.SOLUTION: An excavator shaft 1 from/at which a tunnel excavator 2 starts/arrives includes an earth retaining wall 10 having a steel core material 11 and a cement-based hardened body 12. In the earth retaining wall 10 above a position P where a mouth should be formed as a position from/at which the tunnel excavator 1 starts/arrives, a steel pipe 13 is provided through which the core material 11 is inserted. The peripheral face of the core material 11 inserted through the steel pipe 13 is covered with a resin thin layer material 20 so that the core material 11 can be pulled up from the position P where the mouth should be formed.