ABSTRACT
The Brenner Base Tunnel is mainly composed by two single track Railway Tunnels and an Exploratory Tunnel; Lots Mules 1 and 2–3 and previous Preparatory Lot concern a 22 km long stretch on the Italian side. They cross the South part of mountainous dorsal between Austria and Italy, under over-burdens up to 1850 m, consisting of rocks both of the Southalpine and Australpine domains, separated by the major Periadriatic Fault. More than 30 km of tunnels have to be carried out with dimensions ranging from 7 m (Exploratory Tunnel) to 20 m (Logistics Caverns). This results in an extremely hard logistic, geological and geomechanical challenge. During design, different construction options were evaluated, from all the technical, economic and schedule point of view, duly considering the construction risks. The paper explains the design choice of a mix of Mechanized (TBM) and Mining Methods excavation, identified as the most convenient solution.
