Difficulties in tunneling are contributed by the large size required for vehicular tunnels, the inflexibility of design location, and necessity of handling whatever conditions are encountered in alignment, whether they be solid rock, fault zones, or a mixed face of rock and soil below the water table. Contractors around the world have been turning to mechanized systems of excavation utilizing tunnel boring machines, shield systems, precast concrete segments, or other lining systems offering maximum flexibility for adapting to varying ground conditions. Contrary to a commonly held belief, the primary development frontier is not how to cut hard rock cheaper and faster but how to develop a mechanized system that will reliably advance a tunnel heading in the widely varying conditions often encountered. Several case studies illustrate new approaches taken by progressive contractors in vehicular tunnels around the world.

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Filing Info

  • Accession Number: 00043996
  • Record Type: Publication
  • Report/Paper Numbers: Proc Paper 9204
  • Files: TRIS
  • Created Date: Jun 1 1974 12:00AM