急倾斜煤层可采工艺性评价及应用研究

为了预测急倾斜煤层开采的效果和决策辅助技术，对急倾斜煤层可采工艺性进行综合评价．在急倾斜煤层开采工业性试验及开采实践的经验和统计数据分析的基础上，建立了适合急倾斜煤层地质条件开采工艺性块段评价的层次结构，影响急倾斜煤层开采的复合因素有8个，基元因素13个；运用多指标综合评价方法和模糊数学原理，构造了急倾斜煤层可采工艺性影响因素的评价函数，建立了模糊综合评价模型．用该模型对京煤集团大台煤矿289个工作面进行了评价计算，并且根据工作面块段的评价值对工作面单产进行了预测，结果表明，工作面中1级27个，占9．34％；2级87个，占30．1％；3级112个，占38．75％；4级63个，占21．8％。评价结果与开采结果基本相吻合．     

采煤方法及设备选择决策支持系统的研究

论述了缓倾斜煤层采煤方法选择的评价过程及评价指标，将煤层地质条件评价、可行方案论证、计算机模拟、技术经济分析、模糊评判及多目标评价等方面的内容和方法汇集成完整的数据库、模型库和方法库，建立了具有良好用户界面的缓倾斜煤层采煤方法及设备选择决策支持系统．该系统已在实践中应用．     

缓倾斜煤层合理开采方式的确定

井田合理开采方式的确定是煤矿建设和生产中经常遇到的问题。本文以最常见的缓斜煤层为对象,以大屯徐庄煤矿为典型对这一问题作了系统分析,研究讨论了用多目标评价及多级参数分级决策方法对开采方式的各种方案进行优选的问题,编制了适合于缓倾斜近距煤层群的合理井田开采方式多目标评价的计算机程序。同时结合大屯徐庄煤矿的条件做了具体分析和评价,得到了一些结果。     

倾斜长壁最优方案的选择

本文阐述的评价倾斜长壁开采方案的准则为吨煤费用最小。提出的数学模型中,设有6个变量。借助于电子计算机,对1080个方案进行了计算。计算结果表示在两个诺谟图中。根据煤层数目、层间距、采区尺寸及煤层巷道维护费,可以从图中很快找出一个倾斜长壁开采的最优布置方案来。     

急倾斜煤层开采诱发地表裂缝数值模拟

为了研究急倾斜煤层开采诱发地表裂缝的演化过程,探讨急倾斜煤层开采诱发地裂缝分布规律.利用可描述拉张破裂的有限元方法,对地表裂缝演化过程进行数值模拟.结果显示:最大拉应力集中在地表,地表优先于采空区破裂,采空区下山方向对应的地表一侧形成裂缝.急倾斜煤层开采地表和采空破裂的顺序与水平、倾斜煤层的破坏顺序相反.煤层倾角很陡时,地表先破裂到一定程度后,采空区才开始破裂.煤层倾角很缓或水平时,采空区先破裂,之后地表才破裂.     

急倾斜煤层大推进度巷放开采优化试验研究

厚度10 m以下急倾斜煤层为极难开采煤层,新疆阜康地区急倾斜煤层目前主要采用轻型液压支架放顶煤开采,存在通风不畅和回采率偏低等问题.通过现场调研及可行性论证,对该地区厚度5～10 m急倾斜煤层开采提出了大推进度巷放开采采煤方法,并通过岩石力学试验、物理相似模拟试验、数值分析及理论计算,对该方案进行了优化试验研究.结果表明,密集通风眼大推进度巷放开采不仅能够避免6 m盲巷、保证工作面一直有新鲜空气流通,而且平均回采率达到81.1%,适合在阜康地区推广应用.     

急倾斜煤层跨采区上山回采方案

针对淮南局孔集煤矿开采急倾斜煤层不同阶段进行分析。综合其生产中的先进技术，提出了跨采区上山回采方案，对急倾斜煤层开采技术革新有借鉴价值。     

倾斜煤层开采沉陷预计模型的构建

概率积分法在我国煤矿开采地表沉陷预计领域得到了广泛应用,该方法具有对称分布特征,在水平煤层开采沉陷预计时精度最好,而倾斜煤层开采后地表下沉盆地的形态往往呈现偏态性,采用该方法对其进行预计偏差较大。针对此问题,建立了工作面随体坐标系和地表直角坐标系,利用随机介质理论在工作面随体坐标系中实现单元开采沉陷影响的叠加积分运算,然后将工作面随体坐标系中地表某点的沉陷影响转换到地表直角坐标系中,最终构建地表直角坐标系下的倾斜煤层开采沉陷偏态预计模型。分析认为,倾斜煤层单元开采引起的地表下沉符合威布尔偏态分布规律,结合实例对预计模型的有效性进行了验证。该模型预计精度随煤层倾角的增加而逐渐降低,研究结果可为相似矿区的沉陷预计提供理论和技术支持。     

急倾斜煤层开采地表移动变形数值模拟

针对急倾斜煤层开采复杂的地质条件,对朝阳某煤矿分别选取了六种方案进行模拟,岩层依次变软,得出六种方案的水平和竖直方向的地表变形曲线及模型在x、y方向的等值线图.结果显示:方案一和方案二的最大值分别为0.026 85 m、0.049 39 m;方案三和方案四的最大值分别为0.066 75 m、0.089 4 m;方案五和方案六的最大值分别为0.134 1m、0.260 3 m.可以得出随着弹性模量的减小也就是随着上覆岩层的变软,地表水平和竖直方向的位移都逐渐增大,影响范围也逐渐变大;地表变形的最大值并不在采空区的正上方,而在采空区法线方向与地表的交点左右.可以为研究急倾斜煤层的开采及变形移动规律提供理论支持.     

倾斜长壁工作面老顶岩层破断规律的研究

本文利用弹性基础梁理论,研究了倾斜长壁工作面老顶岩梁的运动和破断规律,分别对仰斜开采和俯斜开采条件下老顶岩层断裂的位置和条件、老顶来压步距等进行了分析.研究表明,倾斜长壁开采时老顶岩梁的初次断裂过程有三种类型,并给出了相应的计算公式。同时分析了煤层倾角和顶板条件对老顶断裂和矿压显现的影响。     

Fuzzy Evaluation of Coal Seam Geological Condition of Fully-Mechanized Face in Ten-Million-Ton Mine

1 IntroductionWith the development of coal mining, the dif-ference in coal seam geological conditions will cer-tainly influence on the adaptability of coal miningtechnology and on coalface outputs, especially theeconomic indicators. To ensure a high efficiency ofcoal mining, coal seam geological conditions mustbe made clear. Fuzzy evaluation here is aiming atconcrete coal seam geological conditions with thecomprehensive view of coal mining. The main ideaof this evaluationis that a coalface is …     

An influence function method based subsidence prediction program for longwall mining operations in inclined coal seams

The distribution of the final surface subsidence basin induced by longwall operations in inclined coal seam could be significantly different from that in flat coal seam and demands special prediction methods. Though many empirical prediction methods have been developed, these methods are inflexible for varying geological and mining conditions. An influence function method has been developed to take the advantage of its fundamentally sound nature and flexibility. In developing this method, significant modifications have been made to the original Knothe function to produce an asymmetrical influence function. The empirical equations for final subsidence parameters derived from US subsidence data and Chinese empirical values have been incorporated into the mathematical models to improve the prediction accuracy. A corresponding computer program is developed. A number of subsidence cases for longwall mining operations in coal seams with varying inclination angles have been used to demonstrate the applicability of the developed subsidence prediction model.     

Evolution of a mining induced fracture network in the overburden strata of an inclined coal seam

The geological conditions of the Pingdingshan coal mining group were used to construct a physical model used to study the distribution and evolution of mining induced cracks in the overburden strata. Digital graphics technology and fractal theory are introduced to characterize the distribution and growth of the mining induced fractures in the overburden strata of an inclined coal seam. A relationship between fractal dimension of the fracture network and the pressure in the overburden strata is suggested. Mining induced fractures spread dynamically to the mining face and up into the roof as the length of advance increases. Moreover, the fractal dimension of the fracture network increases with increased mining length, in general, but decreases during a period from overburden strata separation until the main roof collapses. It is a1so shown that overburden strata pressure plays an important role in the evolution of mining induced fractures and that the fractal dimension of the fractures increases with the pressure of the overburden.     

Research on New Method of Full-Seam Mining for Gently Inclined Thick Coal Seams

The recovery ratio of top-coal caving mining plays a key role in the development of this mining method. For the proposccs to raise the recovery ratio and consideriug heading adva,lce and roadway maiqtenancc, a new method of full-seam mining for gently inclined thick coal seams is put forward on the basis of a thooretic re.search and engineering practice.     

Feasibility analysis of gob-side entry retaining on a working face in a steep coal seam

Based on the decline in exploitation of coal resources, steep coal seam mining and mining face tensions continue to explore the feasibility analysis of steeply inclined faces in the gob. One of the key factors in utilizing the technology of gob-side entry retaining in steep coal seams is to safely and effectively prevent caving rock blocks from rushing into the gob-side entry by sliding downwards along levels. Using theoretical analysis and field methods, we numerically simulated the mining process on a fully-mechanized face in a steep coal seam. The stress and deformation process of roof strata has been analyzed, and the difficulty of utilizing the technology is considered and combined with practice in a steep working face in Lvshuidong mine. The feasibility of utilizing the technology of gob-side entry retaining in a steep coal seam has been recognised. We propose that roadways along the left lane offshoot body use a specially-made reinforced steel dense net to build a dense rock face at the lower head. The results show that the lane offshoot branch creates effective roof control, safe conditions for roadway construction workers, and practical application of steeply inclined gob.     

Gas emission quantity prediction and drainage technology of steeply inclined and extremely thick coal seams

Gas emissions of workfaces in steeply inclined and extremely thick coal seams differ from those under normal geological conditions, which usually feature a high gas concentration and a large emission quantity. This study took the Wudong coal mine in Xinjiang province of China as a typical case. The gas occurrence of the coal seam and the pressure-relief range of the surrounding rock(coal) were studied by experiments and numerical simulations. Then, a new method to calculate the gas emission quantity for this special geological condition was provided. Based on the calculated quantity, a further gas drainage plan, as well as the evaluation of it with field drainage data, was finally given. The results are important for engineers to reasonably plan the gas drainage boreholes of steeply inclined and extremely thick coal seams.     

倾斜矿床露天矿分期境界的优化

本文从系统工程的角度出发,运用运筹学和计算机,对倾斜矿床露天开采分期境界优化的方法和理论进行了探讨;在倾斜矿床露天矿长远规划模型的基础上,建立了分期开采境界优化模型。运用该模型对齐大山露天铁矿进行了分期开采模拟计算,其模拟结果为齐大山铁矿分期境界设计提供了科学的依据。     

回采工艺模式选择专家系统的设计与实现

从煤层赋存条件、地质构造、人员素质及工作面外部环节能力等方面叙述了回采工艺模式的选择，建立了多层次的回采工艺模式选择的专家系统（ＣＭＴＰＥＳ），并重点介绍了知识库和推理机设计．本专家系统已用ＴＵＲＢＯＰＲＯ－ＬＯＧ语言初步实现，其不仅可对新建矿井回采工艺的确定提供理论根据，而且可对生产矿井回采工艺的论证提供技术指导