隧道危岩块体稳定性的地质-几何简明分析法

隧道围岩局部块体稳定性分析是隧道设计和施工过程中必不可少的环节。以地质素描图为出发点，借助投影几何学的地质-几何简明分析法，通过对块体几何作图分析的简化，可以迅速地确定隧道危岩块体的位置、几何形态、塌滑类型以及稳定性系数，从而直接及时地指导围岩支护加固的重点。最后，运用该方法对曼歇3号隧道局部危岩块体的稳定性进行了评价，得出了该处危岩块体的主要破坏方式是直接塌落的结论，指出了隧道围岩支护加固的重点，在地质工程实践中达到了预期的效果。

Simple geology-geometry analytical procedure on stability of tunnel critical rock-block mass

Assessment on stability of partial rock-block mass is essential during tunnel’s design and construction. On the basis of geological sketching explosion views, combined with projective geometry and the block theory, simple geology-geometry analytical procedure simplifies geometrical analysis of critical rock-block mass so as to define its space location, geometrical forms, different type of collapse or slippage, stability factor of single sided or double sided slippage, thus directly instructing purposive reinforcement of tunnel surrounding rock mass promptly. Finally, on the basis of geological sketching explosion views, this new simple analytical procedure is firstly applied to assess the stability of partial critical rock-block mass of tunnel Manxie 3; and a conclusion that plump collapse is the main destructive manner of critical rock-block mass is drawn. It not only assures the safety and continuity in the course of tunnel’s construction, but also has been testified having anticipated good effect in actual geology engineering application.