HYDRAULIC TUNNELER HAS UPSIDE-DOWN DIGGER

Noteworthy design points are described and the operation is outlined of an innovative tunneling system which also includes paving of the tunnel invert without use of inner forms. Details are described of the muck conveying system which embodies a series of steel flights, and in which spoil is dropped into a contractor-built rail car holding 11 to 12 tons. A cycle (one 16-in. liner ring advance) takes about 40 minutes. The machine advances 12 to 16 rings or 15 to 20 ft. per shift under adverse soil conditions. Another feature of the tunneling is the scheme for placing and Striking off the semicircular invert slab. A novel finishing device is a steel strike-off shoe mounted on the end of a pendulum arm, which revolves around a section of pipe located in the eye of the tunnel's radius. The shoe is swung back and forth several times to finish the concrete to spec tolerance. The device can be slid along the pipe as the concreting progresses.

  • Corporate Authors:

    Dun Donnelley Publishing Corporation

    222 South Riverside Plaza
    Chicago, IL  USA  60606
  • Publication Date: 1973-12

Media Info

  • Features: Figures; Photos;
  • Pagination: p. 30-32
  • Serial:
    • Roads and Streets
    • Volume: 116
    • Issue Number: 12
    • Publisher: Donnelley (Reuben H) Corporation

Subject/Index Terms

Filing Info

  • Accession Number: 00264901
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Feb 27 1975 12:00AM