基于离散元方法的深部巷道层状围岩稳定特性研究

Numerical study on bearing behavior of layered rock mass for deep roadway

采用块体离散元方法UDEC,通过细观参数校核及无支护状态的宏观物理-数值模型对比,建立了深部层状围岩巷道模型,分析了4种支护方式对深部巷道层状围岩体承载特性及变形破坏特征的影响。在块体离散元巷道模型基础上,为进一步研究深部矩形巷道层状围岩体承载能力,通过监测模型内部的应力、塑性区分布及顶底板和两帮位移,对不同支护方式的压力拱成拱特性进行了分析。研究结果表明:不同支护方式下深部巷道顶底板及两帮围岩均出现了应力集中区,采用锚杆+锚索+喷射混凝土+工字钢支护后巷道表面收敛程度及围岩的位移均最小,支护效果最明显,对围岩的控制效果最好。研究结果可为实际工程中的矩形巷道层状围岩稳定性控制提供参考。

In this paper, block discrete element method (UDEC) was adopted to establish the roadway model of deep layered surrounding rock by checking microscopic parameters and comparing the macro-physical and numerical models without support. First of all, the bearing characteristics of the roadway under four different support modes (bolt support, dense bolt support, bolt + cable support and bolt + cable + shotcrete + I-shaped steel support) were analyzed by monitoring surrounding rock stress distribution, plastic zone distribution and displacement. Then, the arch forming characteristics of the pressure arch with different support modes were further discussed. The research results showed that the stress concentration areas appeared in the surrounding rock of deep roadway under different support modes, and the convergence degree of roadway surface and the displacement of surrounding rock were at the minimum with bolt + cable + shotcrete + I-shaped steel support. This research will provide reference and relevant basis for the stability control of deep roadway of layered surrounding rock in practical engineering.