Application of Hydrostatic Leveling System in Metro Monitoring for Construction Deep Excavation above Shield Tunnel

The monitoring of the settlement of the shield tunnel plays a very important role in the traffic safety of metro trains. The monitor precision and the timely are required for the settlement of the shield tunnel. The automated monitoring must be introduced to the monitoring work, and becomes powerful monitoring method. The article introduced the measurement principle of the hydrostatic leveling system (HLS), through the hydrostatic leveling system preliminary utilized in metro monitoring for construction deep excavation above shield tunnel. The monitoring data and the construction safety are analyzed. Regularities of settlement of the shield tunnel are summarized. Suggestion is made on the monitoring range.