Water stop promoting the structure of the wellhead in promoting construction

摘要

PROBLEM TO BE SOLVED: To provide a cut-off propulsion structure of a pit mouth for propulsion work capable of achieving installation of protective concrete in the state of leaving a pit mouth supporting portion behind.;SOLUTION: A cut-off propulsion structure of a pit mouth for propulsion work comprises: a cut-off device, the one end of which abuts along an opening edge of the pit mouth and which is fitted with a cut-off rubber 14 in such a manner as to be brought into close contact with an outer peripheral surface of an excavator 6 inserted into the pit mouth along a peripheral edge of the other end thereof; reinforcements 17 and 18 which are assembled in such manner as to surround the cut-off device along an outer peripheral surface of the cut-off device; and a pit mouth supporting section 24 that is integrally molded from concrete in the state of being brought into close contact with the outer peripheral surface of the excavator 6 in such a manner as to surround the cut-off device 9 and the reinforcements.;COPYRIGHT: (C)2012,JPO&INPIT