A description is given of the construction of the 8 mile Baltimore rapid transit system which includes 4.5 miles in tunnels. The system includes nine stations, six of which are underground, and is designed for future extension. Excavation involves soft ground machine tunnelling in alluvial soils and also hard rock drill and blast methods. All six underground stations are being built by cut-and-cover methods - two of the stations are at depths of 100-120 ft. Compressed air is used to stabilize the surrounding ground for excavation with an hydraulic shield. Following normal practice in the USA, steel linings are used except for a 1500 ft experimental section which is being lined with concrete segmental rings. Running tunnels are 18 ft diameter so that the railway will accept current US and Canadian rail cars.

  • Availability:
  • Corporate Authors:

    Morgan-Grampian Limited

    30 Calderwood Street
    London SE18 6QH,   England 
  • Publication Date: 1979-9

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00309921
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD, TRIS
  • Created Date: May 21 1981 12:00AM