浅谈软弱围岩隧道中最优循环进尺的确定

尽管在传统隧道中循环进尺对技术和经济都有重要影响，但是对于它的确定还没有一个条理清楚的程序。研究了还没有施做支护控制的软弱围岩隧道进深的确定问题。一系列的小规模几何模型相似实验和PFC3D分析对掌子面和无支护段的行为模式进行了检测分析。研究结果在表明安全系数和相关行为模式为圆的长度变化关系的“软弱围岩隧道开挖方案条件图”中有体现。在有详细的结构信息，开挖优化和概率设计阶段可以独立进行。可为基坑的优化提供有用的信息。

Brief Talk on the Confirm of Optimal Footage Driving Cycle in Weak Surrounding Rock Tunnel

In traditional tunnel, footage driving cycle has a great influence on technology and economy, however, there is no coherent procedure yet to confirm it. In this paper, the tunnel depth of weak surrounding rock without timbering control is investigated. A series of small - scale geometric model experiment and PFC3D analysis make the inspection and analysis on the behavioral pattern of tunnel face and no - timbering section. The research result is shown in ＂the information drawing of weak surrounding rock tunnel excavation scheme＂ in which the length changing relationship between the safety factor and relevant behavioral pattern is round. It can be carried out independently in the period which has detailed structural information, excavation optimizing and probabilistic design. Useful information can be provided for optimizing the foundation trenches.