分区破裂是深埋隧洞围岩破坏的特定类型,发生围岩分区破裂的条件是存在一个较大的平行于隧洞轴向的应力.通过分析实际工程实例,阐述了发生分区破裂后围岩的应力-应变特征,建立了不同破裂圈界面的应力-应变平衡方程,得出了在不同界面上围岩的径向位移突变,环向位移连续的特征,进而推出新的破裂圈的发生是围岩应力再分布或能量再平衡的结果.通过推导不同相邻破裂圈半径的比值,得到了二者之间的比例关系.通过确定深埋隧洞所处应力环境,提出了发生分区破裂的根本原因是较大的构造应力的影响,并提出了确定应力大小的方法.最后,通过对工程实例的分析,验证了所提结论的有效性.研究结论可以对相关类似工程提供一定的指导意义.%The zonal disintegration is a specific type fracture of the surrounding rock in the deep tunnel,which may take place when the stress is too large and parallel to the tunnel axial direction.In this paper,the stress-strain characteristics of the surrounding rock in the phenomenon of zonal disintegration are explained through an analysis of the engineering examples.A stressstrain equilibrium equation to the different zonal disintegration loop interface is established.Based on it,it is obtained that the radial displacement suddenly changes,and the tangential displacement continues in the loop interface,indicating that the occurrence of the new disintegration loop is due to the stress redistribution or energy balance of the surrounding rock.The ratio of the adjacent disintegration loops' radius is derived to obtain their proportional relationship.The occurrence of zonal disintegration is the result of large tectonic stress in the deep tunnel.The analysis results of engineering cases demonstrate the performance and effectiveness of the proposed model,which could provide a reference for the practical engineering application.
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