A new railroad tunnel which will connect the east and west bound lines out of the city of Oslo is presently under construction. One part of this tunnel goes through bedrock at a depth of 20-40 m below ground surface. Above and along the tunnel there are a number of clay filled depressions in the bedrock. Past experience has shown that leakage in connection with tunnels or excavations very easily can cause reduction of pore water pressures in a relatively thin sandy layer normally found at the bottom of these depressions, thus consolidation of the clay layer. Despite systematic grouting and lining, it has not been possible to prevent significant leakage into the tunnel. The causes and effects of this leakage on pore pressures and settlements in some of the depressions encountered so far along the tunnel are described. Also discussed are various schemes which have been tried to artificially infiltrate water back into the soil/rock mass around the tunnel.

Media Info

  • Pagination: p. 197-213

Subject/Index Terms

Filing Info

  • Accession Number: 00195721
  • Record Type: Publication
  • Source Agency: Engineering Index
  • Files: TRIS
  • Created Date: Jul 31 1979 12:00AM