摘要
This paper describes the construction of a deep station during the work on the extension of Metro Line 5 in Milan, Italy. Operating in an urban context that included the presence of an existing line （Milan Metro Line 1）, the work had to grapple with some very particular problems so as not to interfere with the area＇s normal city life. Several construction choices and technical solutions were adopted to reduce impacts as much as possible and to suit local needs （hydromill diaphragm walls, top down and bottom up techniques, protected TBM （tunnel boring machine） break-in by false tunnels, precasted and casted solutions for internal structures and construction management, etc.）. The contribution points out the attention to the issues that make this activity so particular for excavation, ground support and structural solutions, and also for the split between civil and tunnel works carried out simultaneously on the same site. Underground context, consisting mainly of sands and gravels with presence of water, is shortly presented also in terms of geotechnical parameters.
