STATION EXCAVATIONS IN HARD ROCK FOR THE WASHINGTON METRO

Details are given of the construction of rock caverns for mass transit railway stations in Washington DC. Ten of the stations have been excavated in gneiss, schist and quartz where these vaulted rock excavations measure some 650 ft long, 45-50 ft high and 60 ft wide. The caverns are designed without interior supporting columns. For drilling and roof bolting operations four pneumatic Ingersoll-Rand, three-boom, rampmaster jumbos were used. The drills have penetration rates of 1 m/min on 50 mm diameter blastholes. A stabilator robot shotcrete unit following behind the jumbos spray a 50-100 mm layer of shotcrete to stabilise the rock face.

  • Availability:
  • Corporate Authors:

    Morgan-Grampian Limited

    30 Calderwood Street
    London SE18 6QH,   England 
  • Publication Date: 1979-4

Media Info

  • Features: References;
  • Pagination: p. 57-58
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00197284
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD, TRIS
  • Created Date: Aug 28 1981 12:00AM