针对经典巷道矿压理论在进行深部巷道矿压分析时适用性不强的问题，以非等压条件下圆孔周围塑性区边界方程及蝶形破坏理论为基础，理论推导出非静水压力场条件下圆形巷道围岩主应力方向偏转角度与塑性区边界上一点的极坐标角度的余弦四次隐性方程。基于此隐性方程，采用理论分析、数值模拟和现场试验等综合研究方法，研究了巷道蝶形塑性区分布特征随围岩主应力方向偏转的演化规律，揭示了巷道蝶形塑性区蝶叶方向性的形成机制，并对不同巷道断面形状(圆形、矩形、拱形)、围岩力学参数(软岩、中硬岩、硬岩)以及层状顶板结构(下软上硬型、下硬上软型、软弱夹层型、坚硬夹层型)条件下围岩蝶形塑性区蝶叶方向性的适用性进行了分析;在此基础之上，探讨了蝶叶方向性与围岩变形破坏特征的关系，并对赵固二矿回采工作面运输巷围岩非对称变形破坏机理进行了研究。研究结果表明:蝶形塑性区蝶叶会随主应力方向的偏转而发生偏转，且两者的偏转角度基本相等;同时，巷道断面形状、围岩力学参数以及层状岩层顶板结构均对蝶叶方向性无显著影响，蝶叶方向性具有普适性;受蝶叶方向性的影响，巷道蝶形塑性区的分布特征与围岩变形破坏形态具有一致性，导致蝶形塑性区蝶叶位置的围岩变形破坏相对其他位置严重，造成巷道呈现非均匀变形破坏特征，工作面运输巷围岩现场探测破坏形态与数值模拟塑性区形态基本吻合。

The classical roadway pressure theory is not applicable to the analysis of deep roadway pressure.To solve this problem,based on the boundary equation of plastic zone around circular hole under non isobaric conditions and butterfly failure theory,the cosine fourth order implicit equation of the principal stress direction deflection angle of the surrounding rock of circular roadway and the polar coordinate angle of a point on the boundary of the plastic zone under the condition of non hydrostatic pressure field was deduced theoretically.Then,theoretical analysis,numerical simulation,and field test were used to study the evolution law of butterfly plastic zone distribution characteristics with the deflection of surrounding rock principal stress direction,and the formation mechanism of butterfly directionality in butterfly plastic zone of roadway was revealed.The applicability of butterfly directionality in the butterfly plastic zone of surrounding rock under different roadway section shapes (circular,rec tangular,arch),the mechanical parameters of surrounding rock (soft rock,medium hard rock,hard rock) and layered roof structure (lower soft upper hard type,lower hard upper soft type,weak interlayer type,hard interlayer type) were analyzed.Based on this,the relationship between butterfly directionality and the deformation and failure characteristics of surrounding rock was discussed,and the asymmetric deformation and failure mechanism of sur rounding rock of transport roadway in the working face of Zhaogu No.2 mine was studied.The results show that the butterfly leaf in the butterfly plastic zone will deflect with the deflection of principal stress direction,and the deflection angles of the two are approximately equal.The shape of roadway section,mechanical parameters of surrounding rock and roof structure of layered rock have no significant effect on the directionality of butterfly leaf,and the butterfly directionality is universal.Affected by the directionality of butterfly leaf,the distribution characteristics of butterfly plastic zone in the roadway are consistent with the deformation and failure mode of the surrounding rock,resulting in its deformation and failure at the butterfly leaf position in the butterfly plastic zone is more serious than that at other positions,and leading the non uniform deformation and failure characteristics of roadway.The failure mode of surrounding rock in the transportation roadway of working face is basically consistent with that of numerically simulated plastic zone.

1 塑性区蝶叶形态表征

2 蝶叶方向性形成机制

   2.1 理论分析

   2.2 数值模拟验证

3 蝶叶方向性的适用性分析

   3.1 巷道断面形状对蝶叶方向性的影响

   3.2 围岩性质对蝶叶方向性的影响

4 蝶叶方向性对围岩稳定性的影响

5 工程应用

6 结论