'SENSITIVE' BLASTING

This article describes the construction of the Southern Link underground motorway, which is part of a planned ring road around Stockholm; it includes a route map. This will be the largest road tunnel system ever built in Sweden; the motorway will be 6km long, of which 4.5km will be in twin-tube tunnels. Most of the tunnels will be rock tunnels. Work on the project began in 1998, and the motorway will be opened for traffic in 2003, but the whole scheme will not be completed until 2004. The project has been divided into several different contracts, each of which was submitted to competitive tendering. The tunnels run mainly through good-quality granite, with overburdens usually 5-40m. However, jet grouting and/or ground freezing are applied where the rock is poor or the overburden was insufficient. The work has to be done in such a way that no damage or permanent changes are caused to house foundations, which are on clay in this area. Extensive pre-grouting is required. It is followed by drilling and blasting which is carefully controlled in sensitive areas, including those near buildings and portals. Lighting will be very important, and traffic safety will be enhanced by extensive safety installations and equipment. Ventilation will be longitudinal, so that the tunnel tubes are also ventilation channels.

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  • English

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Filing Info

  • Accession Number: 00799866
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD
  • Created Date: Oct 6 2000 12:00AM