ABSTRACT
The Ceneri Base Tunnel is part of the new Trans-Alpine Railway Line (NRLA). The NRLA axis of the Gotthard also includes the Gotthard Base Tunnel and connections to existing lines. The excavation of the 40 km of tunnels, caverns and cross-link, with maximum rock cover of 800m, involved the crossing of various geological formations consisting of Ortogneiss and Paragneiss rock, and disturbed areas, consisting of cataclasite and kakirite rock, in different percentages. The geo-mechanic behaviour of the different areas, investigated with geological surveys, and monitoring tools, was decisive for the choice of excavation and rock support systems. This paper will examine the types of monitoring applied, and the analysis of the data performed, making correlations between the rock mass, the excavation technique and the geo-mechanical behaviour.
