Total loads modeling and geological adaptability analysis for mixed soil-rock tunnel boring machines
Total loads modeling and geological adaptability analysis for mixed soil-rock tunnel boring machines
复制标题
土石混合隧道掘进机总荷载建模及地质适应性分析
DOI：
10.1016/j.undsp.2021.09.002
复制
发表时间：
2021-10
影响因子：
6.4
通讯作者：
Qian Zhang
中科院分区：
文献类型：
--
作者：
Wencong Qi;Lihui Wang;Siyang Zhou;Yilan Kang;Qian Zhang
岩土界面混合地基是隧道施工中经常遇到的问题。隧道掘进机的开挖荷载受隧道掘进机与岩土层相互作用特性的控制。不同的岩土性质导致了不同的相互作用范围和应力分布。目前已有多项研究对RSI作用下的开挖荷载进行了估算，得出的结论是总荷载随着开挖工作面岩层比例的增加而增大。但是，以往的研究除了对切削齿载荷的计算外，没有考虑到岩土性质的差异。因此，RSI与TBM之间的相互作用特征尚不清楚。分析了TBM主要部件与复杂地质条件（如层状土、层状岩石、RSI条件）的相互作用特征。提出了掘进设备在准静力平衡条件下的总推力和总扭矩计算模型。通过两个典型工程对模型的合理性和适用性进行了讨论和验证。并从开挖难度、总扭矩与总推力的匹配关系等方面讨论了其地质适应性。结果表明：当开挖工作面岩层比例增加时，整体挤压和摩擦载荷的减少量是圆盘刀破碎载荷增加量的1.5倍；总载荷和总扭矩与总推力之比近似线性下降。开挖难度指数与侵彻深度呈幂函数关系。研究结果为隧道施工中设备推进系统的总载荷设计和参数调整提供了重要参考。
Rock-soil interface mixed ground (RSI) is often encountered in tunnel construction. The excavation loads of tunnel boring machines (TBMs) are controlled by the interaction characteristics between TBM and rock/soil layers. The different properties of rock and soil cause the varying interaction range and stress distribution. Currently, there have been several studies available to estimate excavation loads under RSI, and the conclusion is that the total loads increase with increasing the rock layer proportion in the excavation face. However, the previous studies cannot take the difference of rock/soil properties into account, except for the calculation of cutters loads. Therefore, the interaction characteristics between RSI and TBM is unclear. This paper analyzes the interaction characteristics between TBM’s main components and complex geological conditions (e.g., layered soil, layered rock, and RSI condition). A model is proposed to calculate the total thrust and total torque assuming quasi-static equilibrium of the tunneling equipment. The rationality and applicability of the model are discussed and verified by two typical projects. Furthermore, the geological adaptability is discussed in terms of the excavation difficulty and the matching relationship between total torque and total thrust. The results indicate that when the rock layer proportion in the excavation face increases, the reduction of overall extrusion and friction loads is 1.5 times higher than the increase of disc cutters breaking load. The total loads and the ratio of the total torque to total thrust decrease approximately linearly. There is a power function relationship between the excavation difficulty index and the penetration depth. The results of this study provide an important reference for the total loads design of equipment propulsion systems and the parameter adjustment during tunnel construction.