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Tunnel construction in squeezing conditions is very demanding. Difficulties are met in making reliable predictions at the design stage. During excavation squeezing is not easily anticipated, even when driving into a specific geological formation. Squeezing conditions may vary over short distances due to rock heterogeneity and changes in the mechanical and hydraulic properties of the rock mass. Indeed, the selection of the most appropriate excavation-construction method to be adopted (i.e. mechanized tunnelling versus conventional tunnelling) is highly problematic and uncertain.