Abstract In order to solve the "rolling" and "cutterhead pitch" problems encountered by a large diameter shield machine in the process of tunnelling in the curved section of the soft mudstone composite stratum, by analyzing the causes for the attitude destabilization of the shield tunnelling, the commonly used methods in the deviation correction and the corresponding correction principles, the effects of various correction measures are analyzed in combination with the actual correction process on site, and the posture correction technology applicable to the rolling destabilization of the shield. The results show that: (1) When the shield tunnelling is implemented in the soft and hard composite stratum, the complex changes of the stratum environment will easily lead to the instability of the shield posture, and the tunnelling in the long curve section will aggravate the instability; (2) Such corrective measures as adding radial oil cylinder, one-way rotation of shield cutterhead, and adding steel wedge are helpful to improve shield rolling. Adjusting the pressure of the oil cylinder, adding longitudinal oil cylinder and secondary grouting behind the wall are helpful to the adjustment of the shield from "cutterhead pitch"; (3) Auxiliary schemes such as grease and bentonite injection, tool change and butter application are conducive to reducing the constraint of the shield during posture adjustment; (4) For the case similar to the simultaneous instability of "cutterhead pitch" and "rolling" of the shield, it is recommended to first solve the rolling correction of the shield before the problem of axis shifting.
Abstract：
In order to solve the "rolling" and "cutterhead pitch" problems encountered by a large diameter shield machine in the process of tunnelling in the curved section of the soft mudstone composite stratum, by analyzing the causes for the attitude destabilization of the shield tunnelling, the commonly used methods in the deviation correction and the corresponding correction principles, the effects of various correction measures are analyzed in combination with the actual correction process on site, and the posture correction technology applicable to the rolling destabilization of the shield. The results show that: (1) When the shield tunnelling is implemented in the soft and hard composite stratum, the complex changes of the stratum environment will easily lead to the instability of the shield posture, and the tunnelling in the long curve section will aggravate the instability; (2) Such corrective measures as adding radial oil cylinder, one-way rotation of shield cutterhead, and adding steel wedge are helpful to improve shield rolling. Adjusting the pressure of the oil cylinder, adding longitudinal oil cylinder and secondary grouting behind the wall are helpful to the adjustment of the shield from "cutterhead pitch"; (3) Auxiliary schemes such as grease and bentonite injection, tool change and butter application are conducive to reducing the constraint of the shield during posture adjustment; (4) For the case similar to the simultaneous instability of "cutterhead pitch" and "rolling" of the shield, it is recommended to first solve the rolling correction of the shield before the problem of axis shifting.
ZHOU Shengli
.Posture Destabilization and Treatment Measures of Large Diameter Shield in Soft Mudstone[J] MODERN TUNNELLING TECHNOLOGY, 2022,V59(6): 208-215
2022, Vol. 59 