This article reports on the construction of a tunnel under Changi Airport, Singapore, for a new mass transit line, and discusses some of the unusual great difficulties found there. One major problem has been that the route of the tunnel passes through a forest of piles just below a large building. The piles must be supported just above the tunnel, while they are cut below it to allow its excavation. Other piles are within 2m of the tunnel line, which will go deeper than their end points. All these foundations, just under 50 piles, continue to support a five-storey structure above, an airport car park, a finger pier to aircraft being boarded, a bus ramp, and the track of an elevated shuttle train. To do the required tunnelling work, it is necessary to form diaphragm walls from above, and work from cramped spaces inside the buildings to create the tunnel by a top-down method. The results would be disastrous if the buildings moved, and the airport is continually used. The underground station is spectacular and is inside a 215m long box. Most complex of all are two short overrun tunnels going 126m beyond, which pass under buildings and could be used to start tunnels to other terminals. An extra baggage tunnel will pass under one of those tunnels. All the tunnels will be formed by hand mining.

  • Availability:
  • Corporate Authors:

    Miller Freeman

    Calderwood Street
    London,   United Kingdom  SE18 6QH
  • Authors:
    • Greeman, A
  • Publication Date: 2000-8


  • English

Media Info

  • Features: References;
  • Pagination: p. 24-7
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00799863
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD
  • Created Date: Oct 6 2000 12:00AM