Resumo (PT):
Abstract (EN):
The paper presents a solution executed for the connection of a pre-existing metro tunnel made with a tunnel-boring machine to the structure of a station constructed by the cut-and-cover method. The geotechnical conditions of the site were very difficult: 26 m of man-made fill and alluvial soft silty clay and loose sands, with the water level close to the surface. The tunnel was completely covered by these soft soils. The solution consisted mainly in extending the retaining wall of the station beyond the planes of the portals, in order to confine the tunnel in the stretches adjacent to the station, and creating a volume of treated soil by jet grouting limited by the tunnel lining, the stiff layer underlying the alluvial soft ground, the lateral confining walls and the station wall. The paper presents details of the execution and of the performance of the system. Some conclusions are extracted, emphasising the main advantages of the solution.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
15