Control of deformations in the pillar between the twin bores of a tunnel in Aosta valley, Italy
Abstract
About one-third of the 2.7-km long, twin-bore tunnel discussed here traverses a morainic deposit. The ground control problems anticipated in the design and excavation of the tunnel in this weak material are discussed together with the procedures used for controlling the excessive deformations in the narrow pillar between the two bores. The two recommendations for continuing the excavation are to increase the strength of the pillar (widening and/or reinforcement) and to keep the face of the second bore behind the invert of the first bore.
Fields of Study & Subjects
Geotechnical Engineering and Analysis
Tunneling and Rock Mechanics
Geomechanics and Mining Engineering
Publication details
- Journal / source
- CRC Press eBooks
- Pages
- 47–55
- Publication date
- 19 January 2026
- Language
- EN
- Document type
- Book chapter