MINNESOTA'S FIRST MINED HARD ROCK HIGHWAY TUNNEL ALMOST COMPLETE

The first mined hard rock highway tunnel in Minnesota is currently being constructed in an area known as Lafayette Bluff located in the Encampment Forest north of the City of Two Harbors. The $13.8 million, mile-long project includes an 852 foot-long tunnel composed of a 652 foot-long mined section and a 200-foot-long cut & cover portion along with approach roadways. It is described how the use of hard rock mining technology offered many advantages over a more traditional open cut project. The Lafayette Bluff Tunnel will be one of the widest tunnels in North America. Details of the mining element and other construction highlights are described.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/01474820
• Corporate Authors:

  American Association of State Highway and Transportation Officials (AASHTO)

  444 North Capitol Street, NW
  Washington, DC  United States  20001
• Authors:
  • BRAY, J
• Publication Date: 1991-4

Media Info

• Pagination: p. 7-9
• Serial:
  • AASHTO Quarterly Magazine
  • Volume: 70
  • Issue Number: 2
  • Publisher: American Association of State Highway and Transportation Officials (AASHTO)
  • ISSN: 0147-4820

Subject/Index Terms

• TRT Terms: Excavation and tunneling; Mining; Rocks; Tunneling; Tunnels
• Geographic Terms: Minnesota
• Old TRIS Terms: Rock tunneling
• Subject Areas: Bridges and other structures; Design; Geotechnology; Highways; I25: Design of Tunnels;

Filing Info

• Accession Number: 00610755
• Record Type: Publication
• Files: TRIS
• Created Date: Jun 30 1991 12:00AM