薄煤层螺旋钻机采煤方法优化及采场稳定性研究

发布时间：2018-11-14 20:36

【摘要】：薄煤层有多种开采方法，螺旋钻机开采是其中的一种，此采煤方法在我国一些煤矿中已有使用，取得了一定成果。它能够降低煤层厚度开采下限，最低0.4米就可以开采。因工人不进入工作面，安全性高，劳动强度小，与传统薄煤层开采相比，具有更多的优越性。因此，这种采煤方法具有推广应用和研究的价值。论文根据对螺旋钻机采煤方法的现场应用情况和理论分析，详细概括和总结了此采煤方法，并通过相似模拟和数值模拟开展了系列研究，主要工作如下：（1）提出了9种巷道布置-钻采顺序，可在不同条件下选择相适应的方式作为设计考虑。（2）对螺旋钻机采煤方法的重要钻采参数（钻采宽度和煤柱宽度）进行研究，提出了连续多孔钻采概念，以代替传统的单孔钻采方式。连续多孔钻采是指螺旋钻机开采薄煤层时无间隔的连续钻采多个（2个以上）钻采孔再留一定的煤柱。依据钻采力学特点，，按照“梁”的理论进行钻采宽度计算，再用有效面积理论进行钻采煤柱宽度分析，给出了计算式。计算式应该按照钻采空区的不同处理情况进行选取，并指出了连续多孔钻采参数确定的一般方法。（3）进行了物理模拟，研究表明：在开采过程中煤柱及围岩的应力要经历不受影响→受到影响缓慢增大→快速增大→缓慢增大→逐渐减小→趋于一定的稳定值这个过程；应力是向着中间煤柱方向转移的，中间煤柱承受主要载荷，往两边顺次减小；较硬顶板的钻采工作面形成“两边边界煤岩体—煤柱—煤壁”的大支撑结构，当出现大面积来压失稳时，采场煤柱上覆岩层作为整体与边界煤岩体切断垮塌；在一定地质条件下，钻采宽度8米及煤柱宽度2米时，煤柱和围岩没有发生变形等影响钻采的现象，因此连续多孔钻采的方法是可行的。（4）运用FLAC3D数值模拟，探究其围岩及煤柱的稳定性。钻采围岩和煤柱水平方向的拉压应力极低，对煤柱和围岩失稳几乎不起作用；围岩和煤柱主要受竖直方向应力作用，且破坏方式主要为剪切破坏。提出的9种巷道布置-钻采顺序、钻采宽度和煤柱宽度的确定优化了螺旋钻机开采方法。煤柱和围岩稳定性的掌握有利于钻采的矿压控制。理论分析、物理模拟和数值模拟都表明薄煤层螺旋钻机开采采用连续多孔钻采方式的新思路是可行的。这些结果都对薄煤层螺旋钻机开采设计具有一定的参考意义。
[Abstract]:There are many kinds of mining methods in thin coal seam, one of which is spiral drilling machine. This mining method has been used in some coal mines in our country, and some achievements have been made. It can reduce the coal seam thickness mining lower limit, the lowest 0.4 meters can be mined. Because the workers do not enter the working face, the safety is high, the labor intensity is small, compared with the traditional thin coal seam mining, it has more advantages. Therefore, this mining method has the value of popularization, application and research. According to the field application and theoretical analysis of the mining method of spiral drilling machine, this paper summarizes and summarizes the mining method in detail, and carries out a series of research through similarity simulation and numerical simulation. The main work is as follows: (1) 9 kinds of roadway layout-drilling and mining sequence are put forward, which can be considered in different conditions. (2) the important drilling and production parameters (drilling and production width and pillar width) of screw drilling machine are studied, and the concept of continuous porous drilling and production is put forward to replace the traditional single hole drilling and production method. Continuous porous drilling and production refers to the continuous drilling and production of more than 2 drilling holes without interval while the spiral drilling machine is mining thin coal seam and then leaving a certain coal pillar. According to the characteristics of drilling and production mechanics, the drilling and mining width is calculated according to the theory of "beam", and then the effective area theory is used to analyze the width of drill and mining pillar, and the formula is given. The formula should be selected according to the different treatment conditions of the goaf, and the general method for determining the parameters of continuous drilling and production is pointed out. (3) physical simulation is carried out. The results show that the stress of coal pillar and surrounding rock will go through the process of increasing slowly and increasing slowly, increasing slowly and gradually decreasing to a certain stable value during the mining process; The stress is transferred to the intermediate pillar, which bears the main load and decreases successively to the two sides. The large supporting structure of "coal and rock mass, pillar and wall" is formed in the hard roof mining face. When there is a large area pressure instability, the overlying strata on the pillar of the stope as a whole and the boundary coal and rock mass are cut off and collapsed. Under certain geological conditions, when the width of drilling and production is 8 meters and the width of coal pillar is 2 meters, the deformation of coal pillar and surrounding rock does not occur, so the method of continuous porous drilling is feasible. (4) FLAC3D numerical simulation is used to study the stability of surrounding rock and coal pillar. The tensile and compressive stress in horizontal direction of rock and pillar in drilling and mining is very low, which has little effect on the instability of coal pillar and surrounding rock, and the rock and pillar are mainly subjected to vertical stress, and the failure mode is mainly shear failure. Nine kinds of roadway layout, drilling and production sequence, drilling and mining width and coal pillar width are proposed to optimize the mining method of spiral drilling rig. Mastering the stability of coal pillar and surrounding rock is beneficial to the rock pressure control of drilling and mining. Theoretical analysis, physical simulation and numerical simulation all show that the new idea of continuous porous drilling is feasible for spiral drilling machine in thin coal seam. These results are useful for the design of spiral drilling rig in thin coal seam.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD82

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