The tail seal unit which consists of the tail seal which in tail structure

摘要

PPROBLEM TO BE SOLVED: To provide a tail structure of a shield excavator a tail seal exchanging method capable of exchanging a tail seal including the last stage tail seal at a low cost and rapidly regardless of existance or non existance of solidification of a backfilling material and a tail seal unit using the same. PSOLUTION: The tail seal unit is provided with a tail seal unit 7 formed of a slide ring 8 equipped to be relatively displaceable in the axial direction on the inner peripheral face of a tubular tail frame 4b and tail seals 9, 10 pressed on the outer peripheral face of an existing segment 3 fitted to the inner peripheral face of the slide ring 8, a slide means 17 relatively advancing the tail frame 4b against the tail seal unit 7 and disclose the inner peripheral face of the tail frame 4b covered with the slide ring 8 until that moment into the tunnel, and an installation space 21 formed in the inner peripheral face of the tail frame 4b exposed inside of a pit by the slide means 17 for fitting a new tail seal unit 7x. PCOPYRIGHT: (C)2005,JPO&NCIPI