The article examines the problem of water ingress in tunnel workings, with the subsequent lowering of groundwater table and subsidence, following drill-and-blast operations. This subsurface disruption can result in subsidence and damage to buildings and structures. An example is given of a multiple-hole grouting technique used to overcome the problem in the construction of an 1800 M section of a 6 km twin-tube line for the Stockholm Metro. Depth of cover over the 22 sq M tunnels varies from 6-50 M with the overall project 20 M below sea-level. To avoid lowering of the groundwater table a pre-grouting operation was carried out using the Hany multiple hole grouting system. This automatic system delivers grout through hoses into holes drilled in the rock before excavation takes place. Details are given of the Hany system and the drilling and grouting equipment used. (TRRL)

  • Availability:
  • Corporate Authors:

    Morgan-Grampian Limited

    30 Calderwood Street
    London SE18 6QH,   England 
  • Publication Date: 1980-4

Media Info

  • Features: Figures; Photos;
  • Pagination: p. 41-43
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00316581
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD, TRIS
  • Created Date: Sep 16 1981 12:00AM