由于岩土结构的变化,全断面盾构机在掘进过程中推进力和扭矩需要进行适当的顺应性设计以获得良好的掘进效率,以减少刀具磨损和损伤破坏事故的发生。针对盾构机在掘进过程中遇到的典型地质结构,建立地质结构的圆形百分比模型,分析刀盘上不同刀具在掘进过程中载荷受力,建立不同刀具及总扭转载荷的数学表述方法,基于该方法对盾构机在异质岩土结构中旋转时刀盘总扭矩随旋转角度的变化特性进行研究,结果表明,在软岩与硬岩比例大约为30%时刀盘的扭矩载荷波动最大,容易造成刀盘堵转及损伤事故,该可以解释云南上公山隧道掘进时频繁堵转产生机理,为异质岩土掘进时盾构机冗余驱动电机的顺应性设计提供指导。
It is important that the compliance design of tunnel boring machine (TBM) is performed to improve the efficiency and reduce the failure accidents when they excavate in the heterogeneous geologic strata. The equivalent excavating model of the heterogeneous geologic strata has been established based on the typical geological structure in the tunnel construction. The load behavior of the individual cutters was discussed. The mathematical description of total torque on the cutterheads is given in terms of the load of cutter and their locations. The correlation between the torque behavior and the rotating angle of cutterheads is investigated. The results show that fluctuation of torque is dependent on the ratio of hard rock and soft soil on the excavating face. When the percentage of the soft soil is 30%, the fluctuant amplitude is maximum, which may lead to the blockage and failure accidents of driving system. It is in agreement with the engineering case in the Shanggongshan tunnel construction. It can be used in the compliance design of the TBM.