The compliance design on thrust system of shields excavating in various geologic conditions

Abstract

The redundant actuating thrust system is usually employed to comply with the complex load on the excavating face. The control strategy of these hydraulic cylinders is critical to the load transmission. The forces transmission model of the redundant actuating thrust system of shield machines was established based on the screw theory. The force transmission behavior was studied when the shields excavate in the heterogeneous geologic structures containing the hard rock and soft soil. The correlation between the group strategy of the thrust hydraulic cylinder and the load behavior on the cutterhead was discussed. A flexible group strategy on the redundant actuating hydraulic cylinders was proposed in terms of the various loads. It may improve the compliance ability of the thrust system excavating in the heterogeneous geologic structures. © 2009 Springer-Verlag Berlin Heidelberg.