ABSTRACT
“Nesima-Misterbianco” lot I, with its 1.76km-length tunnel excavated with a Ø10.6m EPB is part of expansion project of Catania metro-line. The tunnel is the first application of an EPB through the complex geological context of Catania, characterized by the presence of numerous volcanic formations. The EPB advancement faced and led to a great deal of critical aspects during the excavation: presence of high variability of formations at tunnel faces, abrasiveness, high ground permeability and a high level of cutter wear. An unceasing manual set-up of excavation parameters and ring-by-ring data processing is needed to improve the understanding and knowhow on EPB possible performance in this context. This paper proposes a comparison between principal prediction models in literature and EPB parameters recorded during tunnel excavation, the main focus is understand how the geological context and mixed-face conditions have influenced EPB performance during the excavation.
