平朔东露天矿地下采空区顶板安全厚度及处理研究

发布时间：2018-06-08 22:20

本文选题：平朔东露天矿 + 地下采空区　；参考：《武汉理工大学》2015年硕士论文

【摘要】：平朔东露天矿在资源整合以前是由多个民营企业开采,存在多个地采小煤窑且乱采、滥采现象严重,采场内存在一定数量、情况不明的空区。随着露天开懫作业的进行及暴露时间的增加,可能出现顶板岩体冒落而造成上覆岩层塌陷,威胁着露天作业人员与设备的安全,定量地确定这些地下采空区顶板安全厚度能确保矿山生产安全进行。对东露天矿进行详细的现场地质调查,采用钻孔探测法摸清采空区的形态大小和特征;理论分析采空区顶板破坏机理并计算出顶板安全厚度。采用ANSYS/LS-DYNA动力有限元软件建立含采空区的台阶爆破模型,进行不同跨度不同埋深条件下的采空区顶底板及两侧墙体的应力分析;并通过Midas软件模拟设备静载条件下不同跨度的采空区顶板应力分布特征;最后提出东露天矿地下采空区的治理方法。全文主要研究成果如下:(1)通过对东露天矿岩体进行工程折减,得出数值模拟计算需要的工程岩体力学参数,抗压强度值为8.01MP,抗拉强度值为0.45MPa。(2)通过5种经典理论计算公式得出采空区顶板安全厚度推荐值,即跨度10m时其顶板安全厚度7.4m,跨度15m厚度11.4m,跨度20m厚度15m,跨度25m厚度18.5m,跨度30m厚度23.7m,跨度40m厚度31.5m。(3)综合爆破冲击荷载和设备压力荷载条件下的不同跨度采空区顶板安全厚度,结果表明跨度10m时其顶板安全厚度12m;跨度15m厚度16m,跨度20m厚度21m,跨度25m厚度25m,跨度30m厚度30m;跨度40m厚度42m。(4)提出采空区治理步骤,结合东露天矿实际情况选择合适的探测方法并根据顶板安全厚度(H0)、最大打孔深度(hm)以及空区上缘距上覆台阶面高度(h)三者之间的关系将空区分为3类,并对每类空区根据矿岩稳固条件、治理难易程度再细分三种情况;针对不同类别的采空区提出高效、安全的处理方法即崩落法,并对某一采空区进行实践处理,效果明显达到治理目的。通过上述研究确定了东露天矿不同跨度下采空区的顶板安全厚度,对于顶板厚度不合要求的采空区运用崩落法来治理,消除了东露天矿地下采空区安全隐患。
[Abstract]:Before the integration of resources, Pingshuo East Open-pit Mine was mined by many private enterprises, and there were many small coal kilns and random mining in Pingshuo. The phenomenon of overmining was serious, there were a certain number of empty areas in the mining site and the situation was unknown. With the development of open-pit operation and the increase of exposure time, roof rock caving may occur, which will cause overburden collapse and threaten the safety of outdoor workers and equipment. Quantificationally determining the safety thickness of roof in these underground goaf can ensure the safety of mine production. In this paper, the detailed field geological investigation of East Open-pit Mine is carried out, and the shape and characteristics of goaf are found out by the method of borehole exploration, and the mechanism of roof failure in goaf is analyzed theoretically and the safe thickness of roof is calculated. The dynamic finite element software ANSYS- LS-DYNA is used to establish the bench blasting model with goaf. The stress analysis of roof and bottom slab and both sides wall of goaf with different span and different buried depth is carried out. The stress distribution characteristics of the roof of the goaf with different span under static load are simulated by Midas software. Finally, the treatment method of underground goaf in East Open-pit Mine is put forward. The main research results in this paper are as follows: (1) the mechanical parameters of engineering rock mass needed for numerical simulation calculation are obtained through engineering reduction of rock mass in East Open-pit Mine. The compressive strength value is 8.01MPand the tensile strength value is 0.45MPa.m2) the recommended value of safe thickness of goaf roof is obtained by five classical theoretical formulas. The safety thickness of roof is 7.4m, 15m, 20m, 25m, 30m, and 40m, respectively. The safety thickness of roof in different span under blasting impact load and pressure load of equipment is 31.5 m 路m ~ (3), and the thickness of roof is 7.4m, 11.4m, 20m, 18.5m, 23.7m and 31.5m / m respectively under the condition of blasting impact load and equipment pressure load. The results show that the roof safety thickness is 12m, the span 15m thickness is 16m, the span 20m thickness 21m, the span 25m thickness 25m, the span 30m thickness 30m, the span 40m thickness 42m. Combined with the actual situation of East Open-pit Mine, the suitable detection method is selected. According to the relationship between the safe thickness of roof and the maximum perforating depth (Hm) and the height of the upper edge of the empty area from the top step surface, the empty space is divided into three categories. According to the stable condition of ore and rock, the paper subdivides three kinds of cases into three cases, and puts forward an efficient and safe treatment method, that is, caving method, for different types of goaf, and carries on practical treatment to a goaf. The effect is obvious to achieve the goal of governance. Through the above research, the safe thickness of the roof of the goaf under different spans of East Open-pit Mine is determined, and the caving method is used to treat the goaf which is not in accordance with the requirement of the thickness of the roof, thus eliminating the hidden danger of safety in the underground goaf of the East Open-pit Mine.
【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD327.2;TD824

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