The paper deals with a sewer tunnel, recently excavated in the city of Palermo. The tunnel layout is close to existing urban facilities and residential buildings. The geotechnical profile is quite variable and the soil cover ranges between 7 and 9 m. The groundwater level is located at mid height between the invert arch and the vault of the tunnel. Excavation support was granted by means of the canopy technique, employing micropiles and jet grouting. A detailed monitoring program was also organized and tunnel construction was followed step by step allowing for proper design changes, according to the subsoil conditions met during excavation. The case history is reported by describing the tunnel layout, the geotechnical profile and the monitoring plan. Recorded settlements of the existing structures are analysed, considering the influence of the geotechnical properties of the subsoil as well as the peculiar construction sequence of tunnelling.
Design and construction of a sewer tunnel in difficult site conditions
CROCE, Paolo;
2012-01-01
Abstract
The paper deals with a sewer tunnel, recently excavated in the city of Palermo. The tunnel layout is close to existing urban facilities and residential buildings. The geotechnical profile is quite variable and the soil cover ranges between 7 and 9 m. The groundwater level is located at mid height between the invert arch and the vault of the tunnel. Excavation support was granted by means of the canopy technique, employing micropiles and jet grouting. A detailed monitoring program was also organized and tunnel construction was followed step by step allowing for proper design changes, according to the subsoil conditions met during excavation. The case history is reported by describing the tunnel layout, the geotechnical profile and the monitoring plan. Recorded settlements of the existing structures are analysed, considering the influence of the geotechnical properties of the subsoil as well as the peculiar construction sequence of tunnelling.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
