Numerical Analysis on Non-Uniform Thrust System in EPB Shield Machine Applied in Beijing Metro Line 6

This paper is to investigate the mechanical characteristics of non-equidistant thrust system in an EPB shield machine with a diameter of 6.15 m applied in Beijing Metro Line 6 construction. Firstly, on the ground of tunneling condition, virtual prototypes for traditional even system and the non-equidistant one have been built. Under the same given working conditions, simulation forces from three jacks in two systems have been compared with those numerical ones. Secondly, based on relative coefficient mode, comparison of force transmission performance between traditional even thrust system and the non-equidistant one have been discussed. Finally, the effects from all forces applied by the two kind of different layouts thrust systems have been studied using finite element method. The results shown that the non-uniform thrust system in the EPB shield machine applied in Beijing subway construction has more significant advantages in the aspects of forces transmission performance and the prevention of the collapse of the lining segments.