IF articles

Recent innovations in yield-control support

systems are allowing contractors to increase the rate

of advance when tunnelling in difficult conditions associated

with severely squeezing ground. Such systems are

being implemented and proven in tunnelling projects using

conventional excavation methods. The Saint Martin

La Porte access tunnel along the Base tunnel of the Lyon-

Turin rail line is presented as a case study to illustrate

some of these developments which have been implemented

successfully to deal with severely squeezing conditions

encountered during excavation in a Carboniferous Formation.