2015,7(2):89-96.
According to practical construction case of No.3 and No. 4 entrance / exit tunnel of Zongguan station in the 1st phase of Wuhan Metro Line 3, this paper gives a comprehensive analysis of all kinds of possible emerging risks in the construction process combining the practical monitoring data. Considering that the pipe jacking construction technology has not been widely used in soft soil area like Wuhan, and the constructors lack experience of pipe jacking construction, it would be necessary to the all construction process if related personnel take some actions to prevent and control the existing risk problems in the construction technology. Meanwhile, it could also offer the valuable experiences to similar projects in the future. Through analyzing the process of pipe jacking and practical monitoring data in No. 4 entrance / exit tunnel of Zongguan station, we could draw the following conclusions : (1) Laying the monitoring points in different places of the construction site could effectively avoid the occurrence of risk; (2) During the construction process of No. 4 entrance / exit tunnel, the ground settlement is much larger than the surrounding buildings settlement, the maximum could reach 58.58 mm, and it would gradually increase with the advance of pipe jacking. (3) The settlement of the bridge pier around the tunnel constructed by Rectangular Pipe Jacking Method is very small. The settlement of the bridge pier is far less than 2mm, and the settlement value keeps stable in general.