JOINING METHOD FOR SHIELD, AND STRUCTURE OF ARRIVAL PROTECTIVE BARRIER

PROBLEM TO BE SOLVED: To provide a joining method for a shield which can surely prevent the intrusion of underground water when a new shield tunnel is joined to an arrival pit mouth of an existing pipe or a vertical shaft in a direction crossing the arrival pit mouth of the existing pipe or the vertical shaft, and a structure of an arrival protective barrier. SOLUTION: A steel tubular body 13 through which a cutting reinforcing ring 22 passes is installed on the outer peripheral side in a position to be cut by the cutting reinforcing ring 22 of a shield machine 20 of the existing tunnel 10, so that cut-off material injection holes 14 can be formed in a plurality of places around the tubular body 13. A plurality of U-shaped pipes 15 for injecting cut-off materials are arranged on the inner peripheral side of the tubular body 13. After that, the tubular body 13 is closed with a lid body 16 and held by a support 17; a filling material such as concrete is infilled into the tubular material 13, so that a filling material layer 18 can be formed for the construction of the arrival protective barrier; and the cut-off material is injected into the periphery of the cutting reinforcing ring 22 from the inside and outside of the existing tunnel 10 in jointing with a newly constructed tunnel 20T. COPYRIGHT: (C)2005,JPO&NCIPI