San Pasquale Station of Line 6 in Naples: Measurements and Numerical Analyses

Abstract The paper reports some geotechnical aspects of the design and construction of the San Pasquale Station, intermediate along Line 6 and located close to the sea and at the same time within one of the most fascinating district of the city known as Chiaia borough. The station required an excavation deeper than 25 m, almost entirely located in pyroclastic sand below the groundwater table. The main shaft is 85.5 m long and 24.1 m large, containing also the whole length of the pedestrian platform while a single large section tunnel, built before the excavation of the station shaft, accommodates the two operating rail tracks. In the paper monitoring data will be presented and discussed. Settlements and horizontal displacements represent certainly very significant outcomes among the observed data. Their variations along with time and main construction steps are first of all presented in the paper. The monitoring data have also been submitted to a process of careful interpretation based on the use of numerical analyses to better understand the interaction of deep excavation with urban area. The FEM code Plaxis has been adopted for such a purpose adopting advanced constitutive soil models which are available in the code library.