Improvement on efficiency and reliability of Full-Face Tunneling Boring Machine

目前，各种类型的隧道掘进机(TBM)被广泛用于替代传统的隧道掘进方法。TBM的性能潜在地远远好于传统方法。然而，在对掘进机不利的条件下，掘进机的工作性能很差。因此，为了提高掘进机的掘进效率，测量工作面前方的地质特征是非常必要的。隧道沿线的岩石强度是根据几百米长的路段的实际挖掘数据估计的。然后将估计的强度与基岩测量和施密特-哈默回弹硬度得到的强度进行比较。估计的岩石强度被发现与使用这些调查发现的岩石强度非常一致。此外，还讨论了岩体分类与岩石强度估算之间的关系。估算的岩石强度与岩体分类结果吻合较好。因此，该方法为快速变化的围岩特性合理选择支护方式提供了一种有用的方法，从而防止了事故的发生，缩短了施工时间和费用。

At present, various types of tunneling boring machines (TBMs) are widely used as a substitute for conventional tunneling methods. The performance of TBM is potentially far better than that of conventional methods. However, TBM performance is very poor when applied under conditions that are adverse to TBM.Therefore, measuring geological characteristics forward of the face is essential in order to improve the efficiency of TBM.In the present study, a method for estimating the rock strength of face using TBM cutting force, such as thrust, torque and cutting depth, is proposed. Rock strength along the tunnels is estimated from actual excavation data for sections a few hundred meters in length. The estimated strengths were then compared with those obtained using the bedrock survey and Schmidt-hammer rebound hardness. Estimated rock strengths were found to agree well with those found using these surveys. Moreover, the relationships between rock mass classification and estimated rock strength are discussed. The estimated rock strength was found to be in good agreement with the rock mass classification. Therefore, the proposed method provides a useful method for properly selecting a supporting pattern for rapidly changing rock mass characteristics, thereby preventing accidents and reducing construction time and expense.