坚硬顶板跨上山开采技术研究

发布时间：2018-07-20 19:12

【摘要】：随着我国用煤量的逐年上升,开采量逐年的加大,开采难度的提高,开采过程中事故是常有发生。坚硬顶板的岩层组成成分又是千差万别,再加上顶板冒落没有明显的预兆和产生巨大的冲击荷载的特征,使得坚硬顶板的控制工作也是难上加难。由于顶板控制难度之大,再加上瓦斯、透水、火灾等一些重要因素的影响,这样就使得我国煤炭的采储量受到一定程度的制约。因此,煤矿开采之前要弄清楚具体的开采地质情况以及利用的科学技术手段是至关重要的。随着跨上山开采技术的应用,使得大量煤柱的开采不再被浪费。那么,为我国能源的使用延续了时间。本文是以临汾天煜恒f煤业9202综放面跨上山开采为工程研究背景,通过现场实测数据的收集和整理、实验室对岩样的分析、对建立的力学模型计算以及FLAC3D的数值模拟等一些研究手段,对在坚硬顶板条件下的跨上山开采技术进行了深入的研究,得出工作面在安全开采的前提下,实现了工作面的跨上山开采技术,提高了该矿的经济和社会效益。首先,详细阐述了临汾天煜恒f煤业9202综放面跨上山开采工程概况,三条上山的支护与布置方式及跨上山两种方案的提出。通过实验室的单轴、三轴压缩实验,绘制了应力应变曲线,并将所得的实验结果与工作面岩样物理力学性质中的容重、抗压抗拉强度等参数值进行了比较,数据基本一致,可为数值计算及理论分析提供依据。其次,运用FLAC3D软件,对9202工作面所在顶底板共7个岩层分别进行了模拟。由应力图看出,机巷附近的压应力要比风巷小,风巷周边局部围岩的拉应力比机巷周边围岩应力大。通过三条上山以后,风巷的压应力达到了52MPa;工作面顶底板的拉应力也同时达到了最大值约1.05MPa。依次跨过三条上山时,由塑性图知,塑性区域的分布越来越广,并逐渐向顶底板扩展。采场前后方断面主要承受的是剪切力,容易引起剪切破坏。随着工作面的推进,顶板悬空面积在增大,产生垂直位移的区域也在增大,随着跨上山开采,最大位移区域是处在工作面顶板的中央。位移值是不断增大的,最大位移约为581.49mm。最后,对来压步距的力学模型进行理论分析计算,得出初次来压的步距范围是22.00~49.97m,这与现场实测30m初次来压步距比较接近。周期来压步距范围为7.21~14.49m,与现场实际的12~18m的范围差距不大,而且计算值14.49m与现场所测值很接近。还对支架工作阻力两个模型进行了计算,当考虑老顶对直接顶支撑力的作用时,不管只是考虑顶煤或者只是考虑直接顶板或者考虑顶煤和直接顶板全部高度都存在碎矸石的支撑力,支架都能满足要求。当不考虑老顶对直接顶支撑力时,只有当顶煤和直接顶板全部高度部分都存在碎矸石提供支撑力的时候,支架才能刚好满足有效支撑的要求。
[Abstract]:With the increase of coal consumption, the increase of mining capacity and the increase of mining difficulty, accidents often occur in the process of mining. The rock composition of hard roof is very different, and the roof caving has no obvious omen and great impact load, which makes it more difficult to control hard roof. Because of the difficulty of roof control and the influence of some important factors, such as gas, water permeability, fire and so on, the mining reserves of coal in China are restricted to a certain extent. Therefore, it is important to find out the specific geological conditions and the scientific and technological means before mining. With the application of mining technology, a large number of coal pillar mining is no longer wasted. So, the use of energy for our country to continue for a long time. This paper is based on the engineering research background of 9202 fully mechanized top-coal caving face of Linfen Tianyu Hengfen coal industry. Through the collection and collation of field measured data, the laboratory analysis of rock samples is carried out. Based on the calculation of mechanical model and numerical simulation of FLAC3D, this paper makes a deep research on the mining technology of stepping up the mountain under the condition of hard roof, and draws the conclusion that the working face is in the premise of safe mining. The technology of cross-hill mining has been realized, and the economic and social benefits of the mine have been improved. Firstly, the paper expounds in detail the general situation of the 9202 fully mechanized top coal caving face of Linfen Tianyu Hengfen coal mining project, the support and arrangement of three uphill, and the two schemes of climbing the mountain. Through uniaxial and triaxial compression experiments in the laboratory, the stress-strain curves are drawn, and the experimental results are compared with the physical and mechanical properties of the working face, such as bulk density, compressive and tensile strength, etc. It can provide basis for numerical calculation and theoretical analysis. Secondly, using FLAC3D software, 7 strata of roof and floor in 9202 face are simulated. It can be seen from the stress diagram that the compressive stress near the machine lane is smaller than that in the wind tunnel, and the tensile stress of the surrounding rock around the wind lane is larger than that around the machine roadway. After three hills, the compressive stress of the wind roadway reaches 52 MPA, and the tensile stress of the roof and floor of the working face reaches the maximum value of about 1 05 MPA at the same time. When we cross the three mountains in turn, we can see from the plastic diagram that the plastic region is more and more widely distributed, and gradually extends to the top and bottom plate. The front and rear face is mainly subjected to shear force, which is easy to cause shear failure. With the advance of the working face, the area of roof overhang is increasing, and the area of vertical displacement is also increasing. With the mining up the mountain, the maximum displacement area is located in the center of the roof of the working face. The maximum displacement is about 581.49mm. Finally, the theoretical analysis and calculation of the mechanical model of the initial pressure step are carried out, and it is concluded that the range of the initial pressure step is 22.00 m 49.97 m, which is close to the initial pressure step distance of 30 m measured in the field. The range of periodic pressure step is 7.21 ~ 14.49 m, which is not far from the actual range of 12 ~ 18 m, and the calculated value of 14.49 m is very close to the measured value. Two models of support resistance are also calculated. When considering the effect of the main roof on the support force of the direct roof, Whether considering the roof coal or the direct roof or considering that all the height of the top coal and the direct roof have the support of the gangue, the support can meet the requirements. When the supporting force of the main roof to the direct roof is not considered, the support can meet the requirement of effective support only when the coal roof and the direct roof all the height part of the coal and the direct roof all have the broken gangue to provide the supporting force.
【学位授予单位】：安徽建筑大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD823.97

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