The natural gas pipeline route involves the crossing of the A1 Milan-Naples motorway and the East External Belt Road of Milan by means of a microtunnel with tubular r.c. segments.
Reinforced concrete piles having an internal diameter ID1600 for a length L= 132 m and vertical radius of curve of Rv= 800 m. Drilling works were made in fine soils and were successfully completed without any settlement of the motorway surface, where the earth cover above the microtunnel was approximately 7 m.