PRESTRESSED CONCRETE STRUCTURE FOR LINING WORK, AND ITS FABRICATION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a method capable of repairing or reinforcing a tunnel without violating the clearance for vehicle. SOLUTION: A prestressed concrete structure 3 is formed to an arch shape along the inner surface of the tunnel. A thin portion 5 is fabricated as a prestressed concrete structure between both side portion 6, 6. The thin portion 5 is formed as a recessed portion 4c, and its inner surface is recessed toward the outer surface of the tunnel in the radial direction. The thin portion 5 has main reinforcing bars 8 and distributing bars 9 which are laid overlapping each other and extruded from both the sides to the existing structure. Thereafter, fresh concrete containing a fiber material 12 such as a steel fiber is casted in the thin portion. And the side portions 6, 6 of the existing tunnel structure and the thin portion are joined together by overlapping the main reinforcing bars 8 and the distributing bars 9 protruded from the thin portion 5. By forming two prestressed concrete structures 3 into the shoulder portions of the inner surface of the tunnel, they can be built without violating the clearance for vehicle. COPYRIGHT: (C)2006,JPO&NCIPI