陕北浅埋煤层矿区保水开采影响因素研究.pdf

Study on Influencing Factors of Water Conservation Mining in Shallow Seam Mine Area in the North Shaanxi Province Dissertation ted to Xi’an University of Science and technology In partial fulfillment of the requirement For the degree of Doctor of Engineering By Shi Benqiang School of Energy Engineering Dissertation Directed byHou Zhongjie April，，2012 独创性说明 本人声明所呈交的论文是我个人在导师指导下进行的研究工作及其取得的研究成 果。尽我所知，除了文中加以标注和致谢的地方外，论文中不包含其他人已经发表或撰 写的研究成果， 也不包含为获得西安科技大学或其他教育机构的学位或证书所使用过的 材料。 与我一同工作的同志对本研究所做的任何贡献均已在论文中作了明确的说明并表 示了谢意。 本人论文与资料若有不实，愿意承担一切相关的法律责任。 签名 日期 关于论文使用授权的说明 本人完全了解西安科技大学有保留、使用论文的规定，即学校有保留送交论文的 复印件， 允许论文被查阅和借阅； 学校可以公布论文的全部或部分内容， 可以采用影印、 缩影或其他复制手段保存论文。同时本人保证，毕业后结合学位论文研究课题再撰写的 文章一律注明作者单位为西安科技大学。 （保密的论文在解密后应遵守此规定） 签名 日期 资助项目资助项目本文获教育部博士点基金项目（20050704003）资助 论文题目陕北浅埋煤层矿区保水开采影响因素研究 专 业安全技术及工程 博 士 生师本强 签名 指导教师侯忠杰 签名 摘 要 陕北榆神府浅埋煤层矿区是我国煤炭工业战略西移的首选基地， 是我国目前探明储 量最大的煤田。它地理位置优越，地质构造简单，煤质优良，开采容易，已经成为我国 主要的特大型优质动力煤和出口煤基地。但是，矿区处于干旱半干旱的毛乌素沙漠与黄 土高原接壤地区，水资源贫乏，土地贫瘠，植被稀疏，生态环境脆弱，社会发展水平低。 自然状态下环境质量呈下降趋势。 煤炭工业的大规模开发更加快了该区环境质量的下降 趋势，如何合理有效地开发煤炭资源，保护水资源，促进生态环境的改善，使区域经济 可持续发展是该地区煤田开发过程中面临的一个重大课题。 可持续发展开发本地区煤田 的关键是在保护浅层地下水资源的条件下开发煤炭资源即保水开采。 本文论述了保水开采的影响因素， 认为影响保水开采的主要因素有矿区覆岩的工程 地质特征（包括岩性、地层组合关系、基岩风化带特征） 、地质构造、开采方法、煤柱 的稳定性等。以前的研究者有的主要从采矿方法、有的主要从地质条件或者主要从水文 地质角度研究保水开采，本文尝试综合考虑影响保水开采的各种自然和技术因素，尤其 是覆岩的工程地质特征、地质构造、开采方法等，具体研究各个影响因素是如何影响导 水裂隙带的发育，如何通过控制保水开采的影响因素实现保水开采。综合影响保水开采 的各种因素，提出陕北浅埋煤层矿区保水开采的区域划分体系。 在覆岩工程地质特征对保水开采影响的研究中建立了保水开采的工程地质模型，为 相似模拟试验和数值模拟提供模型依据。在地质构造对保水开采的影响研究中，指出覆 岩中断层的存在提高了导水裂隙带的发育高度，采用长壁间隔式开采实现保水开采时， 覆岩中存在断层时工作面的推进距离要小于无断层时的情况。 研究了断层活化突水的力 学机理，指出断层倾角决定了断层活化的形式，并推导出断层不同活化形式时的临界采 深和长壁间隔式开采工作面临界推进距离的计算公式。 以燕伙盘井田为例探讨了断层断 距与断层活化的关系。采用相似模拟实验和数值模拟，以大柳塔煤矿为例研究基岩中含 有断层工作面不同推进方向时保水开采的工作面合理推进距离，得出基岩厚度分别为 15m、30m、42m、54m 和 60m 时采用长壁间隔式采煤保水开采工作面的推进距离，回 归出工作面的推进距离与导水裂隙带高度之间的经验公式， 而且得出从断层上盘向下盘 推进比反向推进时导水裂隙带的发育高度要大的结论。 煤柱的稳定性是保水开采实现的 一个关键问题， 在建立的保水开采的工程地质模型的基础上研究了长壁间隔式开采煤柱 的合理宽度，结果表明 15m 是煤柱的合理宽度。 在开采方法对保水开采的影响研究中，分析采空区覆岩的移动规律，分别对砂基型 和砂土基型矿区提出相应的保水开采方法。在砂基型矿区应用固体力学理论，建立保水 开采的关键保护层判据，提出通过选择合理的开采方法（包括长壁间隔式开采、分层开 采等）使覆岩中的关键保护层不破断，导水裂隙带不发展到基岩上部的隔水层达到保水 开采的目的。 在砂土基型矿区采用开采损害学中地表移动变形和采动岩体内部移动变形 预计的方法， 考虑覆岩中隔水土层的膨胀性计算浅埋煤层砂土基型矿区开采后隔水土层 中裂隙的破坏深度，同时借鉴相似模拟实验确定导水裂隙带的发育高度，最后计算采高 不同时这两种裂隙之间的隔水保护层厚度， 当隔水保护层厚度满足规定要求就可以实现 保水开采，从而确定砂土基型矿区保水开采的合理开采方法。以陕北浅埋煤层矿区两个 不同覆岩结构煤矿保水开采方法的选择为例验证了研究结果的可行性， 同时应用相似模 拟试验和数值模拟验证了计算结果。 最后根据保水开采的需要对矿区的地层结构进行分类。 根据采空区上覆岩层不同的 岩土体类型及工程地质性质对保水开采影响作用的研究， 综合考虑影响保水开采的各种 自然和技术因素， 对矿区的地层结构根据保水开采大致分类的结果以及保水开采影响因 素的研究结果提出陕北浅埋煤层保水开采的区域划分体系， 得出不同区域潜水不发生流 失、地表不荒漠化的正确采矿方法和合理设计参数及技术措施，为矿区保水开采的宏观 决策提供参考。 关 键 词浅埋煤层；保水开采；工程地质模型；断层；关键保护层判据； 煤柱稳定性；保水开采区域划分 研究类型应用研究 * *Fund Item This dissertation sponsored by Doctor Education branch of learning fund of Ministry of Education 20050704003. Subject Study on Influencing Factors of Water Conservation Mining in Shallow Seam Mine Area in the North Shaanxi Province Specialty Safety Technology and Engineering Name Shi Benqiang （（Signature）） InstructorHou Zhongjie （（Signature）） ABSTRACT Yushenfu shallow seam mine area in the north Shaanxi province is the preferred base that mine industry of our country strategical moves west, and the biggest reserves coalfield known in our country now. It has predominant geographical location, excellent mine character, ease mine condition, so, it has became our country primary export mine base of excellent character dynamic mine. But, the coalfield locates arid-semiarid area which Maowusu desert and loess altiplano borders on. In the area, the water resource is lithe, the land is leanness, the vegetation is sparse, the zoology environment is flimsy, the social development level is low. It’s environmtntal quality puts up the descendent current in natural state. The exploiture of minal industry quickens the descendent current of the environmtntal quality. It is a fatal problem that how to reasonal and effective empolder the coal resource, how to protect water resource, how to accelerate the mend of zoology environment, how to make the area economy continuable development. The key that the coalfield empoldered continual is that the coalfield is empoldered under the condition protecting the ground water. The influencing factors of water conservation mining were researched in the paper. The influencing factors of water conservation mining have the geotechnical character of overburden strata including lithology,the combined connection of strata, the weathering cingulum character of bedrock, geological structure, mine , the stability of coal pillar etc. er researcher on water conservation mining from aspects of mining . geology condition or hydrogeology，All technical factors of influencing water conservation mining were researched synthetically in the paper，especially included geotechnical character of overburden strata included， geological structure and mine . All factors that influencing the development of water fluid crack were researched idiographic. That water conservation mining through controling the influencing factors of water conservation mining was researched. Synthesizing all factors effecting water conservation mining, the water conservation mining area divisiory system in the north Shaanxi province shallow saem mine area was provided. The geotechnical model of water conservation mining was established in the research of the geotechnical character of bedrock, providing a model gist for similitude simulation test and numercial simulation. In the research of the influence of geologica structure to water conservation mining, the default in the bedrock hight the height of water conducted fissure zone. When the mine of water conservation mining is long wall interval mine, the advancing distance of work face when the bedrock has default is less than the advancing distance when the bedrock has not default. The mechanics mechanism of the default activation was researched, pointed that the dip angle of the default decide the of default activation, deducted the calculational ular of critical mine depth and the advancing distance when the default activates. Taking Yanhuopan mine for example，research the relation between the the default distance and default activates. Taking Daliuta mine for example, with similitude simulation test and numercial simulation, the work face advancing distance for protecting water mine were researched when the bedrock have default and the direction of work face adnancing is different, educed that the distance of work face when the bedrock thinckness are 15m, 30m, 42m, 54m and 60m, educed the calculational ular between the the work face advancing distance and the height of water conducted fissure zone. The stability of coal pillar is a key question achieving water-protecting mine. The paper researched the reasonable width of the long wall interval mine based the geotechnical model of water conversation mine.The research results showsthe width of 15m is reasonable width of coal pillar. In the research of influence of mining to water conservation mining, in sand-bedrock-coal mine area， throught researching the law of overlaying stratum, applying the theory of solid mechanics, this paper founded the key protecting stratum criterion, offering a academic calculational for the water conservation mine in the coal mine of the differing structural overiaying statrum, at the same time, validating the feasibility of the criterion mplifying the choosing of the for shallow coal layer, validating the calculational result applying the similitude simulating experiment and numerical simulation. In sand-soil-bedrock-coal mine area， The breached depth of fracture was calculated in shallow seam covered with rock soil and sand after mine considering the dilatability of clay aquiclude, adopting the estimation of the ground movement deation and the movement deation in the interior of mining rock in Mining Damage, simultaneity ascertaining the the height of water flowing fractured zone utilizing similitude simulation experiment. Finally, the thickness of aquiclude protection among two fracture was calculated when the mine highness is different. The water conversation mine was achieved if the thickness of aquiclude meet prescribed requirement, so, the reasonable mine of water conservation mine was confirmed in shallow seam mine area covered with rock soil and sand. The was corrected, valiating with locate mine practice and similitude simulation experiment. Finally，the paper researched the affecting factors including the type of rock and soil, the geotechnical character of rock and soil, the geological structure，the hydrological conditions and the of mine etc. The paper researched function that the different rock and soil type and it’s geotechnical character effect water conservation mine, classified the mine area stratum according the need of water-protecting mine. According the research of function that the different rock and soil type and it’s geotechnical character effect water conversation mine, providing the area divisiory system in the north Shaanxi province shallow saem mine area, finding the correct mine , reasonal designed parameter and technical measure protecting ground water, preventing upper hungriness, providing the reference for macroscopical decision-making of water conversation mine. Key words Shallow seam Water conservation mining Geologic technical model Default Key protecting stratum criterion The mine pillar stability The district partition system of water conservation mining Thesis Application Study 目 录 I 目 录 1 绪论........................................................................................................................................1 1.1 问题的提出与研究的目的和意义.................................................................................1 1.1.1 矿区煤矿开采对水资源及环境的影响................................................................1 1.1.2 我国水体下开采的研究历史及现状....................................................................3 1.2 浅埋煤层保水开采研究现状.........................................................................................4 1.2.1 保水开采研究的历史和现状................................................................................4 1.2.2 浅埋煤层保水开采研究现状................................................................................6 1.2.3 其它有关研究现状................................................................................................9 1.3 本文主要研究内容及关键问题...................................................................................10 1.3.1 主要研究内容......................................................................................................10 1.3.2 研究关键问题......................................................................................................12 1.4 研究方法及技术路线...................................................................................................13 2 陕北浅埋煤层矿区地质条件及采煤方法概况..................................................................14 2.1 矿区地理位置及地形简介...........................................................................................14 2.2 矿区工程地质条件概述...............................................................................................14 2.2.1 矿区地层、岩性及地质构造..............................................................................14 2.2.2 煤层、覆盖层物理力学性质..............................................................................16 2.3 矿区采煤方法简介.......................................................................................................21 2.4 本章小结.......................................................................................................................22 3 覆岩工程地质性质对保水开采的影响..............................................................................24 3.1 矿区覆岩岩性、岩体结构对保水开采的影响研究...................................................24 3.2 地层组合关系对保水开采的影响研究.......................................................................25 3.3 矿区基岩风化带对保水开采的影响研究...................................................................26 3.4 岩土体工程地质性质对保水开采的影响研究...........................................................27 3.5 工程地质模型在保水开采研究中的应用...................................................................28 3.5.1 工程地质模型简介..............................................................................................28 3.5.2 保水开采工程地质模型的建立..........................................................................29 3.5.3 工程地质模型在保水开采研究中的应用..........................................................29 3.5.4 保水开采工程地质模型的建立..........................................................................31 3.5.5 以保水开采工程地质模型为基础对矿区保水开采的研究..............................31 3.6 本章小结.......................................................................................................................36 目 录 II 4 矿区地质构造对保水开采的影响及防治..........................................................................37 4.1 覆岩中断层活化突水的力学机理...............................................................................37 4.1.1 断层对覆岩活动及导水裂隙带发育的影响......................................................37 4.1.2 断层活化突水的力学机理..................................................................................38 4.1.3 断层活化时临界开采深度和长壁间隔式开采断层活化工作面推进距离......42 4.1.4 覆岩中断层活化突水的力学机理在保水开采研究中的应用..........................44 4.1.5 断层断距对断层活化突水的影响研究..............................................................45 4.2 断层对导水裂隙带发育影响的相似模拟试验...........................................................46 4.2.1 矿区断层概况......................................................................................................46 4.2.2 断层对导水裂隙带发育影响的相似模拟试验..................................................47 4.3 断层对导水裂隙带发育影响的数值模拟...................................................................51 4.4 含断层不同基岩厚度矿区的保水开采分析...............................................................52 4.5 本章小结.......................................................................................................................53 5 矿区开采方法对保水开采的影响分析..............................................................................54 5.1 陕北浅埋煤层矿区的覆岩移动规律...........................................................................55 5.2 长壁间隔式开采方法对保水开采的影响...................................................................56 5.2.1 长壁间隔式保水开采关键保护层判据的建立...................................................57 5.2.2 保水关键保护层判据在砂基型浅埋煤层的应用..............................................59 5.2.3 长壁间隔式保水开采煤柱稳定性研究..............................................................60 5.3 长壁开采方法对保水开采的影响...............................................................................69 5.4 保水开采实例的模拟实验和数值模拟................................................