Abstract: The control of the chamber pressure in shield tunneling is of great importance for the effective control of the ground surface settlement, the ensuring of the tunneling safety and the energy saving. The optimum selection procedures of the chamber pressure and the identification approaches for the mechanical parameters of soil strata are systematically reviewed. The optimmum control methods for the chamber pressure is discussed in detail. The nonlinear control model of the chamber pressure and the identification of the model parameters are proposed respectively. Furthermore, it is proposed that the rotation speed of the screw conveyor and the advance speed of the shield machine should be adopted as controlled variables and the optimised algorithms should be used so as to improve the selfadaptibility and selfcontrolability of the chamber pressure of shield machines. 

Key words: EPB shield machine, pressure control, parameter identification, pressure chamber