According to practical construction case of No.3 and No. 4 entrance / exit tunnel of Zongguan station in the 1^st 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.

The foundation pit dewatering of subway station during excavation is an important part of the work progress.However, the job location of the subway station is generally located in the region of high population flow, and the foundation pit dewatering always brings some bad influence on the surroundings.So the foundation pit dewatering should be studied and analyzed.Based on a metro station of Line No.6 of Wuhan Metro, this paper explains the change law of surrounding building settlement and deformation of retaining structures by using the practical nonitoring data during the process of foundation pit dewatering.Main conclusions are as below:1) in terms of the influence of surrounding buildings, the effect of external foundation pit dewatering is much bigger than that of internal foundation pit dewatering; 2) the effect of external foundation pit dewatering can reduce the active earth pressure of the foundation pit lateral in some degree, and then reduce deformation of retaining structures; 3) the soil property and condition of foundation pit dewatering would have a great impact on the deformation of retaining structures.