复合岩层下岩石掘进机刀盘载荷特性研究

Load characteristics of the TBM cutterhead under mixed-face rock ground condition

针对岩石掘进机在复合岩层掘进时地质条件多变、刀盘受力复杂的问题,建立了岩石截面圆分层模型,基于滚刀受力模型,构建了刀盘载荷描述方程。分析了刀盘受力分布特征,着重研究了岩石单轴抗压强度、分层比对刀盘动态掘进载荷的影响以及推力-扭矩之间的复杂耦合关系。结果表明:刀盘上滚刀受力随着安装半径增大而减小;随着岩石强度的增加,刀盘的推力、扭矩增大;随着分层比的增大,刀盘的推力、扭矩减小;当分层比为0.5时,刀盘的径向力和倾覆力矩最大;分层比一定时,两种岩石单轴抗拉强度相差越大,径向力和倾覆力矩越大;对于给定的岩石成分,刀盘推力和扭矩近似呈幂函数关系。通过对比秦岭隧道TB880E施工数据,对提出的计算方法和结果进行了验证。

This study establishes a circular hierarchical model for a rock section to deal with the varied geological conditions and complex cutterhead load in the tunnel boring machine tunneling process under a mixed-face rock ground condition.Accordingly,a cutterhead load description equation is established based on the hob load model.The stress distribution features of the cutterhead are analyzed.Moreover,the effect of the uniaxial compressive strength and the hierarchical ratio of rock on the dynamic tunneling load of the cutterhead and the complex coupling relation between thrust and torque are mainly investigated.The results show that the hob load on the cutterhead decreases with the increase of the installation radius.The thrust and the torque of the cutterhead increase following the increase of the rock strength.Furthermore,the thrust and the torque of the cutterhead decrease with the increasing hierarchical ratio.The radial force and the overturning moment of the cutterhead reach the maximum when the hierarchical ratio is0.5.Meanwhile,for a given hierarchical ratio,the greater the difference between the uniaxial tensile strength of two types of rocks the larger the radial force and the overturning moment.For the given rock components,the thrust and the torque of the cutterhead keep the relation of approximate power function.The proposed calculation methods and results are verified by comparison with the TB880E construction data of the Qinling Tunnel