Geomechanics and Tunnelling Issue 6/2011

Cover Story: The Châtelard access tunnel for the Nant De Drance pumped storage power station was driven in 2009.

The portal represented a great challenge for the designer and the contractor because the railway line from Martigny to Chamonix is only 3 m above the top heading. The support at the portal consists of a reinforced concrete beam, prestressed anchors 25 to 35 m long and 9 m long rock bolts (see report on page 627).

Topics of Geomechanics and Tunnelling 6/2011:

• Durchmesser Line Zurich
• Nant De Drance pumped storage plant
• Linth-Limmern pumped storage plant
• Segment design
• LCPC abrasivity coefficients
• Recycling of tunnel spoil