论文部分内容阅读
目前地下结构地震动力分析主要研究围岩响应特征,对围岩中赋存的岩体结构的动力响应规律、塌落机制还缺乏深入研究。结合大岗山水电站工程地下洞室群,基于块体理论选取3种不利地质结构组合作为地下洞室群动力分析的主要结构形式,接着运用离散元程序UDEC研究两种地震动工况作用下不同不利地质结构组合切割的地下洞室围岩动力响应、变形特征以及节理的张开、滑移特征,分析开挖面附近块体的塌落机制。研究结果表明,陡倾角结构面切割形成不利地质结构对地下洞室围岩变形破坏机制影响较大;在地震荷载作用下,陡倾不利地质结构沿节理面的滑塌具有突发性,并且塌落模式随地震强度增加可能发生变化。
At present, the seismic dynamic analysis of underground structures mainly studies the characteristics of surrounding rock response, the dynamic response rules of rock mass structure in surrounding rock and the slump mechanism. Combined with the underground caverns in Dagangshan Hydropower Station project, three kinds of unfavorable geologic structure combinations are selected as the main structural forms of dynamic analysis of underground caverns based on block theory. Then the discrete element program UDEC is used to study the effects of two kinds of earthquake conditions Dynamic response and deformation characteristics of surrounding rock of open caverns cut by unfavorable geological structure and the features of joint opening and slipping are analyzed to analyze the slump mechanism of blocks near excavation face. The results show that the formation of unfavorable geological structure by steep dipping structure surface has a great influence on the deformation and failure mechanism of the underground caverns. Under the action of seismic load, the steep dipping geological structure along the joint surface has a sudden collapse and collapse Falling modes may change as the seismic intensity increases.