ABSTRACT
The new Tribunale station of Naples Metro Line 1 does not require very deep excavations. Nevertheless, its design implied an accurate preliminary study and the resolution of relevant issues in consideration of the particular environment in which it is to be built. The site where the station is located, in fact, shows some peculiarities that strongly influenced the definition of the design solution. The selected area falls among buildings having direct shallow foundations, that in some cases are only few tens of centimeters apart from the earth retaining walls along the perimeter of the station. From the geotechnical point of view, the subsoil is characterized by a sequence of incoherent soils, mainly of pyroclastic origin, with interbedded peaty soil layers, the thickest of which is found few meters below the design bottom of excavations; groundwater table is close to the ground surface. Issues arising from the subsoil conditions are discussed, and the design solution is described. The results of a preliminary trial field test aimed to select the most appropriate injection parameters for jet grouting are also reported.
