Study On The Method Of TBM Cutter Load Prediction And Layout Based On The Rotary Cutting

The development and utilization of underground space has become an important way to solve the traffic, water conservancy and the discharge of pollutants. Hard rock tunnel boring machine is applied widely with its high security, high efficiency and low cost for hard rock tunnel excavation construction. As one of the most important parts in TBM, cutter head’s performance has relationship with the performance of the whole machine. In terms of performance requirements of the cutter wear, efficient cutting rock and cutter layout in different areas, combined with the rotary cutting and theory analysis method, the effects of cutter’s installation parameters, excavation parameter on the cutter’s load and excavation performance have been further studied. Moreover, cutters’ layout has been researched.In term of the cutter ’s movement, the rotary cutting model is established. Based on that, the effect of installation parameter on the cutter has been studied. The study proves that the vertical force and rolling force have little relationship with the cutter installation radius; but the lateral force becomes larger with installation radius increasing.And according to the grooves cut by the previous cutter provide a free-face for the subsequent cutter, the effect of the free-face on mechanism of rock fragmentation has been analyzed and the result is verified. The study prove that the closer to the free-face, the smaller of the cutter’s load; the rock’s equivalent plastic strain shows skewed distribution, which skews to free-face. On the basis of that, the influence of cutting order of inside and outside cutter on cutter ’s load is analyzed, the study shows that: compared with the first cutter, next cutter’s load is small.The effect of the TBM operating parameters(cutter penetration and cutter-head speed) on cutter’s load is also studied. The result proves that: cutter’s vertical force and rolling force become large along with the cutter-head speed increase; the relationship of cutting coefficient and penetration is linear and cutter’s load become large along with penetration increase. In term of the minimum principle of specific energy, the method of TBM operation parameter combination is put forward: large penetration with low speed and small penetration with high speed.Lastly, on the basis of the researches, the reasonability of center cutter’s layout, which character “-” style, is analyzed and the improvement of the center cutter’s installation angle is proposed: cutter’s front part rotates an angle to cutter center, and the more near the center, the greater the angle of rotation. Consideration of layout constraints of normal cutter and cutter equal wear principle, the layout method of inner cutter advance outer cutter is put forward for normal cutters. The simulation model of gage cutter is established and mechanism of rock fragmentation is studied. The results show: more energy of rock is used to develop sides crack; the space of adjacent cutters is so large that rock ridge exits always. In term of gage cutter layout, a method of gage cutter layout is proposed: we should set the distance between the tips of adjacent cutters as the actual cutter spacing, rather than on the projective plane measured blade spacing.