Abstract: For EPB (earth pressure balance) shield tunneling, one must properly choose driving parameters to maintain face stability and reducing soil displacement and ground subsidence. In this paper, to research the relationship among shield machine parameters and its impact on the ground displacement by in-site monitoring of Hangzhou metro line shield tunnel construction. The work for in-situ monitoring a shield tunnel construction includes: measuring ground settlement, lateral displacement, excess pore pressure and recording the working parameters of the shield machine. The results show that: the fluctuation for the total thrust force, the earth pressure on chamber and the torque of cutter disc are basically synchronous; ground settlement are mainly influenced by soil removal efficiency before the shield machine arrivals; construction settlement are in inverse proportion to the pressure difference between the inside and outside of the soil chamber; the excess pore pressure begins to decrease rapidly after the shield tail passes through for 0.5 to 1 days; and it completely disappears after 10 days. Settlement after construction is divided into the accelerated subsidence stage and the slow subsidence stage. It accounts for more than 50% of the total ground settlement; and it continues to develop slowly after the dissipation of the excess pore pressure.

Key words: shield, excess pore pressure, soil displacement, long term settlement