ABSTRACT
The paper presents the application of the ground freezing for the construction of the cross-passages in the downtown stretch of the Milan Metro Line 4. The design requirements of the ground freezing, as well as the materials and equipment used will be described in detail; the design criteria will be focused by means of analytical and FEM analyses, concerning the thermal and static behavior of the frozen ground during excavation. The monitoring system to follow up and calibrate the freezing process will be illustrated too. Finally, some aspects and detailing deriving from the jobsites and construction process will be described, which represent a lesson learned very useful for future applications.
