PIPE ROOF RECEIVING FRAME USED AS START PORTAL WALL

摘要

PROBLEM TO BE SOLVED: To provide a pipe roof receiving frame used as a start portal wall attaining safe and reliable rectangular pipe conduit jacking construction by preventing looseness and collapse of the ground at the upper part of a rectangular pipe conduit, and preventing inflow of sediment into a shaft from the outer peripheral surface of the rectangular pipe conduit in rectangular pipe conduit jacking work. SOLUTION: The pipe roof receiving frame used as the start portal wall constructed directly above the rectangular pipe conduit is composed of a pipe roof formed by constructing shafts on both sides of a buried section of the rectangular pipe conduit and jacking and burying pipes in parallel between both shafts so as to be located directly above the rectangular pipe conduit; a rectangular pipe roof receiving frame installed to cover the outer periphery of the rectangular pipe conduit while supporting the pipe roof from below; and the start portal wall wherein a cut-off ring having a rectangular hole smaller than the outer dimension of the rectangular pipe conduit is stuck to the peripheral surface behind the pipe roof receiving frame. COPYRIGHT: (C)2007,JPO&INPIT