TBM rescue shaft and Freezing works


Cairo Metro line 3, near El Gish; Cairo

National Authority of Tunneling

Main contractor:
Egyptian French Joint Venture for Cairo metro line 3 phase 1

Construction period:
2009 - 2010

Project description:
During the tunneling works for Cairo underground metro line 3, a dramatic collapse happened. The tunneling machine (TBM) has been buried at depth of about 30 meter under the street level. Bayer Egypt has been immediately awarded a contract for special tasks to rescue the machine.

Scope of Works:
• Stabilizing and strengthen the collapsed mass by using cement grouting.

• Construct deep secure shaft by installing a diaphragm wall shaft 18 meter diameter, 1,200 mm thickness and 95 meter depth.

• ground water control by supplying and installing of freezing work for the soil around the buried machine for about 20 meter long to allow the main contractor to dismantle the machine and get it out in order to continue the tunneling works.