条带式残煤工作面过空巷顶板应力和围岩变形规律研究

发布时间：2018-05-30 23:44

本文选题：条带式 + 残煤复采　；参考：《太原理工大学》2015年硕士论文

【摘要】：一直以来，煤炭作为我国能源行业的主体，在国民经济的发展中起着很重要的作用。但是我国煤炭资源一直存在着回采率低、资源浪费的现象。在当前我国煤炭资源需求量巨大且不断增长的情况下，提高煤炭资源回收率势在必行，进行已采煤层的复采是提高煤炭回收率的重要途径。而且对于煤矿企业而言，复采能够提高经济效益，有效解决矿井的采掘接替，延长衰老矿井的服务年限。本文针对条带式残煤赋存实际情况，运用弹性力学分析，三维相似模拟试验和数值模拟相结合的方法，对条带式残煤复采进行基础性的分析研究。针对条带式采煤法开采后的煤层残留的煤炭资源，本文对残留煤柱及煤柱顶板进行受力分析。根据AH Wilson煤柱理论，条带煤柱由于不同的受力作用分为边缘屈服区和内部核心区,而顶板应力主要由煤柱核区承担，煤柱边缘由于应力集中作用下孔隙裂隙较为发育。煤柱上方顶板受三轴应力作用，旧采空巷上方顶板由于没有煤柱的支撑而易破断、垮落。在受力分析的基础上，针对山西煤炭运销集团阳城西河煤业的地质条件及煤层赋存状况，利用太原理工大学自行研制的三维试验台进行模拟试验。考虑工作面现场实际状况，试验设计不同形式的复采工作面：房柱式、条带式以及房柱式和条带式混采的工作面。试验设计分两步开采，第一步以柱式开采法对煤层初次模拟开采，间隔一定时间后，第二步针对旧采残煤进行模拟复采。在模拟过程中观察记录顶板应力、顶板下沉位移以及相关的试验现象。本文详细阐述了30°倾角条带式工作面复采过程中开切眼、斜过空巷时顶板应力和位移的变化规律和围岩破坏规律,老顶的初次来压和周期来压步距以及来压现象。依据试验模拟和工程实践，文章以阳城西河煤业实际赋存条件为基础建立了残煤复采的有限元模型，利用FORTRAN语言编写有限元程序对条带式残煤复采进行数值模拟。模拟结果显示：工作面横过空巷对顶板和煤柱上的应力分布有很大影响，，横过空巷使工作面前方顶板应力重新分布，煤柱受力状态改变。
[Abstract]:Coal, as the main body of energy industry, plays an important role in the development of national economy. However, there is a phenomenon of low recovery rate and waste of coal resources in China. With the huge and increasing demand for coal resources in China, it is imperative to improve the recovery rate of coal resources, and it is an important way to improve the recovery rate of coal seams. Moreover, for coal mining enterprises, remining can improve economic efficiency, effectively solve the mining replacement of mines, and prolong the service life of aging mines. In this paper, according to the actual situation of the occurrence of strip residual coal, the basic analysis and research on the remining of strip residual coal are carried out by using the method of elastic mechanics analysis, three-dimensional similarity simulation test and numerical simulation. Aiming at the residual coal resources of coal seam after strip mining, this paper analyzes the residual coal pillar and the roof of coal pillar. According to the AH Wilson pillar theory, the strip pillar is divided into the edge yield zone and the inner core area due to different forces, while the roof stress is mainly borne by the coal pillar core area, and the pore fissure is more developed in the coal pillar edge because of the stress concentration. The roof above the coal pillar is subjected to triaxial stress, and the roof above the old goaf roadway is easy to break and collapse because there is no pillar support. On the basis of stress analysis, aiming at the geological conditions and coal seam occurrence status of Xihe coal industry in Yangcheng city of Shanxi Coal Transportation and Marketing Group, a simulation test was carried out on a three-dimensional test-bed developed by Taiyuan University of Science and Technology. Considering the actual situation of the working face, different types of remining face are designed and tested: roof pillar type, strip type, roof pillar type and strip type mixed mining face. The test design is divided into two steps. The first step is the first simulated mining of coal seam by pillar mining method. After a certain time interval, the second step is simulated remining for the old mining residual coal. In the course of simulation, the roof stress, roof sinking displacement and related experimental phenomena were observed and recorded. In this paper, the variation law of roof stress and displacement and surrounding rock failure law, the first and periodic pressure step and pressure phenomenon of main roof during the remining process of 30 掳inclined strip working face are described in detail. Based on the experimental simulation and engineering practice, the finite element model of residual coal mining is established on the basis of the actual occurrence conditions of Xihe coal industry in Yangcheng city. The finite element program written by FORTRAN language is used to simulate the remining of strip residual coal. The simulation results show that the stress distribution on the roof and coal pillar is greatly affected by the cross goaf of the working face, and the stress distribution of the roof in front of the face is redistributed and the stress state of the coal pillar changes by crossing the goaf.
【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】：TD322

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