Determine of face pressure and thrust force TBM in alluvial deep tunnel

Estimation Face pressure and Thrust force of TBM are one of the basic requirements in mechanized boring. In case of incorrect estimation, there is a possibility of face instability, shrinkage of shield and machine stuck, which leads to costs increasing and prolonged completion time of project. The Kani Sib tunnel consist of two sections of rock and alluvium. Due to the presence of underground water, low mechanics rock parameters and high overburden on alluvial section, this section is one of the most dangerous parts of the tunnel. For that reason, in this paper, estimation of face pressure and trust strength in mechanized excavation of the alluvial section has been studied. At first, in order to do this, required face pressure for maintenance was calculated by analytical method and verified by numerical method. After checking the accuracy of selected pressure, the pressure on the shield and thrust force, which includes force applied from face, shield fraction force, disc cutter force and tension force of the shield, was determined.