SHIELD DEVICE AND EXISTING PIPE REPLACING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a shield device capable of being used in not only an existing tunnel pipe line having a circular cross section but also an existing tunnel pipe passage having a non-circular cross section when digging around the existing tunnel pipe line and provide a new tunnel pipe line along the existing tunnel pipe line in an outer peripheral part of the existing tunnel pipe line. SOLUTION: This shield device 1 is provided with a digging means 3 provided with a cutter bit 32 turning around a shaft center in substantially orthogonal direction to the direction of excavation and a removing means 4 for removing an existing pipe 100. A plurality of digging means 3 are arranged so as to surround outer periphery of the existing pipe 100. An outer peripheral region of the existing pipe 100 is digged and a new pipe 101 is installed while removing the existing pipe 100 using the shield device 1.