TUNNEL BORING IN DIFFICULT ROCK CONDITIONS WITH A FULLFACE MACHINE AS PART OF THE ILANZ POWER STATION PROJECT. SECOND INTERNATIONAL TUNNELLING SYMPOSIUM, MUNICH, 12 APRIL 1989

This paper describes various aspects of the construction of the head race tunnel for the Ilanz Power Station project in the Upper Rhine Valley, Switzerland. This 12.5 km tunnel has a finished diameter of 4.6 m and channels the driving water to the power station. The following topics are discussed: (1) petrography; (2) types of support method used; (3) tunnel heading equipment; (4) envisaged and actual operational procedures; (5) fast rock deformation; (6) cave-ins above the Tunnel Boring Machine (TBM) cutting head; (7) normal tunnel heading with systematic support installation; (8) TBM performance data; (9) upkeep and maintenance of the TBM. In the author's view, this project has again demonstrated that the mechanical full-face heading of tunnels is possible, even under difficult and very variable geological conditions. However, it is important that contractors are provided early with exact predictions about the geological conditions likely to be met. The ideal tunnel boring machine for future similar projects would be designed with: (1) an additional water-powered cutting head drive for slow rotating speeds at high torque; (2) a variable cutting head diameter; (3) a shield enabling a tubbing ring to be placed in the shield tail; (4) a door in the cutting head, which could be opened to access the face in front of the head; (5) a machine room sufficiently spacious to conduct the required support work. A TBM should be developed to drive tunnels quickly and effectively whatever the geological conditions, but perhaps this aim is an impractical dream. The German title for this paper is as follows: "Tunnelauffahrung mit einer Vollschnittmaschine im Rahmen des Kraftwerkprojekter Ilanz in Schwierigen Gesteinsverhaeltnissen". For the covering abstract of this conference see IRRD 824157.

• Corporate Authors:

  Mining Journal Limited

  60 Worship Street
  London EC2A 2HD,   England 
• Authors:
  • Marty, T
• Publication Date: 1989-4

Language

• Undetermined

Media Info

• Pagination: p. 14-20
• Serial:
  • World Tunnelling and Subsurface Excavation Special
  • Publisher: Mining Journal Limited

Subject/Index Terms

• TRT Terms: Conferences; Construction; Deformation; Design; Full face tunneling; Petrography; Rocks; Timbering; Tunneling machines; Tunnels
• Geographic Terms: Switzerland
• Subject Areas: Bridges and other structures; Construction; Design; Geotechnology;

Filing Info

• Accession Number: 00498522
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Files: ITRD, TRIS
• Created Date: Sep 30 1990 12:00AM