Abstract:
To elucidate the mechanism of shield-strata interaction and enable accurate attitude control, a theoretical calculation method for axis deviation based on incremental process and spatial coordinate transformation was proposed on the basis of shield-strata interaction model considering active articulation. Furthermore, by designing the deviation correction curve and using the shield-strata interaction model, the propulsion moment was solved to achieve deviation control. The proposed deviation solution and control method were validated through a case study of the BinZhong interval in Fuzhou Binhai Express. The influence of composite strata and active articulation on deviation correction trajectory was carefully studied, and the corresponding control strategy was subsequently summarized. Some conclusions could be drawn as follows. 1) Based on the shield-strata interaction and incremental process, the shield axis deviation can be solved accurately, and the influence of active articulation can not be ignored. 2) In the composite strata, attitude adjustment may cause the actual correction trajectory deviate from the optimal correction curve, and the nonlinear distribution of the propulsion moment will increase the difficulty of attitude control significantly. 3) The existence of active articulated angle leads to a certain asymmetry in the distribution of additional displacement, and increasing active articulation can reduce the additional displacement effectively. 4) For the composite strata, the active articulation cooperative control can not only satisfy the optimal correction curve but also reduce the propulsion moment effectively, thus achieving efficient deviation control. These researches can provide some theoretical support for the prediction and control of axis deviation during shield tunneling, and also provide basis for the subsequent thrust allocation of cylinders.