安徽潘二矿东二采区胶带机巷围岩稳定性控制技术

Stability Control Technique of the Surrounding Rock of Belt Conveyor Roadway in Second East Mining Area of Pan'er Coal Mine in Anhui Province

安徽潘二矿东二采区胶带机巷受两侧轨道巷和回风巷的影响,掘进过程中产生了大变形,围岩稳定性难以控制。采用FLAC3D数值分析软件,研究了该矿东二采区井底车场巷道群在不同开挖顺序下围岩应力场、位移场及塑性破坏区的分布特征,并结合深部岩巷支护理论提出了胶带机巷的锚杆、锚索联合支护方案。研究表明:(1)巷道围岩应力大小、分布状态和扩散形式受开挖顺序的影响较小;(2)3种开挖顺序(轨道巷→胶带机巷→回风巷(方案Ⅰ),胶带机巷→轨道巷→回风巷(方案Ⅱ),轨道巷→回风巷→胶带机巷(方案Ⅲ))对应的巷道群最大位移值均出现于胶带机巷拱顶和底板中部,胶带机巷是该矿东二采区井底车场巷道群围岩稳定性控制的重点对象;(3)底板是巷道围岩破坏深度最大的部位且在巷道施工过程中得不到及时支护,故而选择对于底板破损范围最小的方案Ⅲ为巷道群施工的最优开挖顺序;(4)锚杆、锚索联合支护方案实施后,巷道围岩变形速率小于0.1 mm/d,巷道水平收敛、拱顶下沉和底鼓趋于稳定,表明该方案能够有效控制该矿东二采区胶带机巷围岩稳定性,可为类似地质赋存条件的巷道支护设计提供借鉴。

The belt conveyor roadway in the second east mining area of Pan＇er Coal Mine in Anhui Province is affected by the both sides of track roadway and return air roadway,large deformation of the roadway is occurred during the process of roadway excavation,the stability of surrounding rock is difficult to control. Based on FLAC3 Dnumerical analysis software,the distribution characteristics of the stress field,displacement field and plastic failure zone distribution of the surrounding rock of roadway group of shaft station of the second east mining area of the mine under the action of different excavation sequence are analyzed,besides that,the integrated supporting scheme based on anchor rob and anchor rope is proposed based on the supporting theory of deep rock roadway. The study results show that：（1）the influence degree of roadway excavation sequence to the magnitude of stress,distribution status and diffusion form of the roadway surrounding rock can be ignored;（2） the maximum displacement value of roadway group is appeared in the middle of arch roof and bottom plate of belt conveyor roadway under the three excavation sequences（track roadway→belt conveyor roadway→return air roadway（scheme Ⅰ）,belt conveyor roadway→track roadway→return air roadway（scheme Ⅱ） and track roadway→return air roadway→belt conveyor roadway（scheme Ⅲ））,therefore,the belt conveyor roadway is the key study object of the surrounding rock stability control of roadway group of second east mining area of the mine;（3） the bottom plate is the site with the greatest damage depth and can not be supported in time during the roadway excavation process,the damage scope of scheme Ⅲ to roadway floor is minimum,therefore,it is the optimal roadway excavation sequence;（4） after the implementation of the integrated supporting scheme based on anchor rob and anchor rope,the deformation rate of roadway surrounding rock is less than 0. 1 mm/d,the horizontal convergence,subsidence of arch roof and floor heave of roadway tent to be stable,which further indicated that the integrated supporting scheme proposed in this paper can effectively control the stability of surrounding rock of belt conveyor roadway in second east mining area of Pan＇er Coal Mine,it can also provide some reliable reference for the design of supporting scheme of the roadways with the same geological conditions of the roadway group of shaft station of the second east mining area of the mine.