贵州省腾龙煤矿溃水溃矸事故形成机制分析

腾龙煤矿10903工作面发生了离层水导致的溃水溃矸事故,通过事故现场、涌水情况、溃入物质及支护变化进行了事故类别判断。为研究溃水溃矸的形成机理,通过分析工作面顶板地质结构及含水层特征,阐明了工作面发育离层水的地质条件;基于采场顶板覆岩组成、离层相似模拟试验,指出煤层上部的长兴组灰岩是控制覆岩形成离层空间亚关键层,长兴灰岩水是离层水的主要补给水源。分析研究了事故发生前工作面迎头构造发育、采掘及顶板支护变化,指出离层水发育、断层破坏及支护缺陷导致顶板碎裂岩体架前切冒,形成了溃水溃矸。     

深部开采底板隔水关键层受局部高承压水作用破坏理论分析

大量实测地质资料与防治水实践证实,深部煤层开采底板含水层存在大量的局部高承压水区域,在强开采扰动下极易诱发底板突水灾害。基于“下三带”、“关键层”理论,将局部高承压水与底板隔水关键层简化为圆筒力学模型,分析研究隔水关键层在局部高承压水作用下的屈服破坏机制,得到了隔水关键层发生屈服的4个临界水压值公式;对各临界水压值进行区间划分,分析不同区间隔水关键层的屈服状态,确定了局部高承压水致使隔水关键层屈服破坏两个阶段的水压判据平衡方程,得出了奥陶系顶部岩层作为隔水关键层剩余隔水能力的计算表达式,并反演得到了开采深度上限、下限公式。结合九龙矿深部开采实际,对所建力学模型进行了验证与应用,进而提出了防止局部高承压水致灾的相关措施,对实现深部煤层安全带压开采具有重要的理论指导意义。     

煤矿保水开采技术现状及其发展

针对采煤过程对区域水文地质的影响和对地下水资源的破坏问题,论述了煤矿顶板水保水开采的理论基础、主要影响因素和技术研究现状,并介绍了陕西榆林市榆阳区煤矿保水开采的成功经验。研究结果表明,根据关键层理论、开采对岩层移动影响及离层规律和水在裂隙岩体中的渗流规律等理论,通过留设防水煤柱、充填开采和注浆加固等方法,抑制岩层导水裂隙带的发育和隔水关键层的离层和断裂,控制岩层潜水的渗流速度是解决煤炭生产中水资源破坏问题的根本方法,具有良好的经济和社会效益。      

坚硬顶板采场采空区岩层离层遥测研究

利用梁弯曲理论,根据岩层间变形不协调性关系,建立了坚硬顶板离层的判别条件,并指出了相应参数对顶板变形的相对影响程度。采用遥测技术监测坚硬顶板采场采空区岩层离层,结果表明,遥测系统可以有效采集到顶板岩层离层发育信息,通过监测曲线的分析,能够确定采空区顶板产生离层的位置,进而可预测出顶板垮落厚度。利用遥测系统采集到采空区顶板失稳前的离层信息,及时采取相应的措施,可保证坚硬顶板煤层安全开采。     

宁东鸳鸯湖矿区红柳煤矿顶板砂岩突水机理分析

宁东鸳鸯湖矿区地处西北干旱地区,但其红柳煤矿1121综采工作面在初采期却经历了4次较大规模的突(涌)水,最大突水量达3 000m3/h,工作面被迫两次停产.通过对采场水文地质条件及覆岩离层分布规律的深入分析研究,可以认定该工作面的周期性突水为煤层开采后顶板砂岩中聚集的离层水所致.在此基础上,总结了开采过程中对煤层顶板砂岩含水层离层水进行有效疏放的方法与成功经验.该研究对宁东鸳鸯湖矿区及其他开采侏罗系煤层矿井的防治水工作具有同等重要意义.     

新集二矿1306工作面矿井涌水量研究与防治措施

根据新集二矿1306工作面地质与水文地质资料，以及邻近1307工作面开采的相关资料，开展了1306工作面煤层开采覆岩地质破坏特征与矿井涌水量预测的研究，获得了13-1煤层采动对顶板覆岩产生的变形及破坏状况，1306工作面开采时得预计涌水量。以此为依据，全面制定了1306工作面开采的综合防治水措施。     

影响覆岩离层注浆减沉效果的地质因素

煤层开采后,采空区上覆岩层内产生离层现象,注浆充填离层可以减小地面沉陷。覆岩离层注浆减沉效果受离层带地层条件、离层围岩透水性和工程地质特性的影响,表现为离层的形成、宜于注浆的离层带的位置、注浆液的保存与支承力的维持。      

缓倾斜地层顶板离层水对综采工作面的危害及防治探讨

以重庆松藻矿区在打通的一综采工作面缓倾斜地层中掘进时发生的两次顶板水灾为例,对其顶板突水原因进行了探讨。通过分析该矿区的矿井地质及水文地质条件,认为矿井充水水源为上覆地层的离层水。该矿井的M7-3煤层开采后,导水裂隙切穿了上覆地层长兴组灰岩,贯通了玉龙山一段灰岩隔水层,进入玉龙岩二段岩溶裂隙含水层。由于含水层的上覆岩层在采掘过程中,因岩性差异发生不均衡沉降,形成了大量的离层空间。离层空间吸收、储存的大量地表降雨在采掘工作面推进到一定位置时,就会发生突水。据估算,S1821工作面上覆岩体离层、裂隙储水空间按三分之一计算为2.064×105m^2,与该工作面抢险救灾期间排出的涌水量基本吻合。根据该矿离层水的赋存特点,提出了保证排水系统畅通,加强采煤设备管理,提高采面设计水平的防治水对策。     

煤层顶板导水裂隙带发育高度工程地质模拟研究——以黑龙江省新发煤矿29~#煤层为例

煤层顶板导水裂隙带发育高度是煤矿设计部门在留设防、隔水煤柱时必须考虑的一个重要参数,对煤矿水体下采煤、顶板防治水具有重要意义。采用实验室工程地质模拟方法,对新发煤矿29#煤层顶板导水裂隙带发育高度进行模拟,模拟的导水裂隙带发育高度为26.3 m;运用关键层理论,计算的导水裂隙带高度为28.29 m。综合确定导水裂隙带发育高度为26.3 m。实验室工程地质模拟方法及应用实例为地质条件相似矿区解决开采上限、留设防(隔)水煤柱等问题提供了方法和数据支持。     

采场覆岩裂隙发育及高位钻孔优化设计——以祁南煤矿34_下2工作面为例

为了有效地提高高位钻孔的瓦斯抽采效果,采用数值模拟方法分析了祁南矿34下2工作面开采过程中覆岩的裂隙发育规律和离层率变化规律。判定了煤层上覆岩层冒落带和裂隙带分布范围;确定了钻孔法距参数的最佳范围为距32煤层顶板12~22 m的岩层区域。研究成果可为其他工作面高位钻孔的优化设计提供参考。     

平煤八矿己15-13030工作面煤层顶板突水溃砂可能性评价

煤矿突水溃砂灾害的发生与煤层上履含水层性质、岩性特征及破坏程度等诸多因素有关。通过研究己15煤层顶板基岩与第四系底部的含、隔水性能及顶板覆岩岩性组合特征,计算出一次全部开采3．6m煤层时,其导水裂缝带最小发育高度为38．46m,最大为47．95m,确定了采煤活动导致的上覆顶板含水层发生水力联系的范围,认为己15—13030工作面煤层开采时发生顶板突水的可能性不大;计算一次全部开采3．6m煤层时,防砂安全垂高最大为23．5m．防塌安全煤岩柱最大垂高为12．5m,结合煤层顶板基岩及第四系底部岩层的水文地质特征,认为工作面回采时顶板溃砂的可能性也不大。强调在生产过程中,要加强顶板涌水的观测,同时增加现有排水系统的排水能力,从而为工作面安全回采提供支持。     

顶板离层水突涌模式及预防技术模拟研究

为预防顶板离层水突涌产生的安全事故,提出了部分充填方案进行模拟研究。首先通过现有资料总结分析全国发生的多种离层水害事故,深入研究离层积水致灾模式;然后以陕西某矿首采区1307工作面的离层水害事故为例,分析其水文地质条件、上部含水层和离层水突涌的关系,利用3DEC数值软件模拟工作面顶板离层空间发育特征;最后根据该矿的实际情况,提出部分充填开采方式预防离层水突涌的技术措施,并对该矿的部分充填方案进行优化模拟研究。研究结果表明:根据发生条件的不同将离层水突涌划分为5种模式,离层积水过程分为初始积水期、积水至满期和裂隙扩展期;在保持充填率不变的情况下,随着走向采宽和充填宽度的同时同量增加,充填体对上覆岩层支撑作用逐渐增强,离层下部隔水层出现两侧应力增大现象,最佳部分充填方案为采宽80 m,充填宽度80 m,为顶板离层水害的预防提供新的思路。      

铜川玉华煤矿顶板离层水突水机理与防治

陕西铜川玉华煤矿一盘区1418工作面,回采期间发生多次突水事故,对煤矿的正常生产和人员的生命安全构成严重威胁。从本井田地质和水文地质资料入手,分析了工作面突水的背景、水源、通道等,得出洛河组下段砂岩裂隙含水层水为离层空间充水的主要水源,煤层采动后形成的导水裂隙带为主要的导水通道。通过理论分析和模拟研究覆岩移动破坏规律,分析确定导水裂隙带发育过程和离层空间可能发育的位置,离层水形成、发展及突水过程,从而总结出玉华井田1418工作面顶板离层水突水机理,为矿井后期实现安全高效生产提出切实有效的防治水措施打好基础。      

我国煤矿离层涌突水致灾机理及其防控关键技术研究进展

离层水害严重影响煤矿安全,明确其突水致灾机理及防控技术的研究现状对促进煤矿安全生产具有重要作用。本文系统地总结论述了离层动态发育机制、突水致灾机理和突水预测预控技术3个方面的研究进展。离层随工作面推进过程呈现动态发育的特征,当某一层位离层具备密闭可持续的离层空间、补水通道、稳定的补给水源、突水通道这4个条件后即存在突水致灾的可能。进而,当离层存在上位高强度岩层破断产生的强冲击、离层积水产生的静水压、采场持续性回采活动的强扰动3个动力源中的一个(及以上)时,离层即发生涌突水。对离层水害的治理可从预防和预控两个角度入手,预防手段包括基于实用矿山压力理论、关键层理论构建离层发育层位预判模型及通过调整工作面推进速度和采高、运用绿色开采技术等减缓覆岩的运移和沉降,预控手段包括超前疏放水、钻孔截流、地面排水等。最后,指出了当前离层水害的研究过程中亟待攻克的难题,如积水探测技术不够精准、超前疏放水技术体系不够完善等,并展望了光纤探测技术、“地面+井下”抽疏(截)联动预控方法、一种无损采矿方法等防治离层水害的新方向。     

On prevention and mechanism of bed separation water inrush for thick coal seams: a case study in China

Bed separation can occur in overlying strata, especially in hard and soft interbedded roof strata. If these strata prone to form bed separation are rich aquifers, water can accumulate into bed separation and maybe cause a serious water hazard under the condition of water inflow passages existence. Therefore, studying these types of roof water inrush mechanisms, forecasting roof water inrush, and formulating preventive and control measures in advance are extremely important to a mine. In this paper, we takes the typical case of water inrush in the workface number 1121 at Hongliu coal mine as an example, and study the mechanism of water inrush in detail. Primarily, field drilling with water leakage and color TV observations showed that the maximum height of the water conducting fractured zone was 12.50 times the thickness of the coal seams, which spread to the overlying coarse-grained sandstone aquifer. Secondly, the numerical simulation indicated that bed separation storage space was prone to form under the combination of coarse-grained sandstone and mudstone geological structure. The detection using UWTEM revealed that the groundwater accumulated in this bed separation and formed a water bag (bed separation water). When the water bag reached a certain degree, water bursting happened with the main roof collapsing. Finally, prevention, effective drainage methods, and successful experiences with bed separation water have been summarized, and it will have a major significance to coal mines suffering from bed separation water inrush.     

厚砂砾含水层下特厚煤层综放开采防治水技术研究

水帘洞煤矿地表水系发育,煤系地层上覆的白垩系洛河组和宜君组巨厚层状砂砾岩含水层,含水丰富,对矿井的安全开采构成了威胁。在详细分析矿区顶板含水层特征、隔水层岩性组合特征及隔水性能基础上,采用比拟法计算了综放条件下顶板导水裂隙带发育高度,并用数值法研究了不同采宽条件下顶板导水裂缝带发育规律,预计了工作面涌水量,为评价煤矿综放条件下工作面安全回采可行性提供了科学的依据。     

Study on the Development Laws of Bed-Separation Under the Hard-Thick Magmatic Rock and its Fracture Disaster-Causing Mechanism

Based on the analysis of dynamic phenomena under the condition of high-located hard-thick (HLHT) stratum of one coal mine, along with the similar material simulation and theoretical analysis, the characteristics of bed separation development and cracks distribution under the HLHT stratum are studied. This paper proposes a discriminating method for overlying strata Three Zones considering the influence of HLHT stratum. The development laws of cracks and disaster-causing mechanism of hard-thick magmatic rock in different strata are respectively analyzed. The studies show that in line with the working face advancing direction, the height of bed separation under the magmatic rock increases in the trend of “Increase–Stability–Decrease”, and the width of bed separation increases linearly. The width of bed separation reaches the maximum before the first breaking of magmatic rock, the bed separation completely closes after the breaking. There are no obvious bed separations during the period migration of magmatic rock. Along the direction of the height of roof, the development of bed separation is characterized by bottom-up jump based on the key strata. The analyzed results of “Three zone” height obtained by the discriminate method of overlying strata Three Zones which is based on the key strata theory and the S–R instability theory are in line with the actual facts. When the hard-thick magmatic rock is in the fractured zone, large amounts of gas and water are easy to accumulate in the bed separation space and “O” ring space around the gob. The first breaking of magmatic rock may induce bed separation gas outburst and water inrush. When the hard-thick magmatic rock is in the sagging zone, the long-term stability of magmatic rock will not cause serious disasters. But with the adjacent working face mining, bed separation gas and water often become a safety hazard.     

大采深工作面煤层底板采动破坏深度测试

针对邢东矿大采深的情况,利用现场底板注水试验对2121工作面底板采动破坏深度进行了测试研究,依据单位注水量的动态变化以及注水孔与采线之间的距离关系,确定了底板破坏深度。试验结果表明:该工作面底板破坏深度为32.5~35m,比300m采深以内的工作面实测深度(9.15~12.0m)增加2倍以上,说明随着开采深度的增加,煤层底板采动破坏深度呈明显增大的趋势,因此,在水压和破坏深度二者同时增加的条件下,2121工作面深部煤层开采的突水危险性远远大于浅部煤层。测试结果为邢东矿大采深工作面的防治水方案的制订提供了科学依据。      

Numerical simulation on tendency mining fracture evolution characteristics of overlying strata and coal seams above working face with large inclination angle and mining depth

In order to master the tendency mining-fracture-evolution characteristics of overlying strata and coal seams above working face with large inclination angle and mining depth in mining process, the 1221 working face in Zhao mine is selected as the engineering background and a mathematical model is established. The displacement variation, stress and strain of overlying strata and coal seams are simulated by using ANSYS software. In the mining process, the movement characteristics, displacement variation laws and fracture evolution characteristics of overlying strata and coal seams above working face with large inclination angle and mining depth along inclination direction are discussed. Simulation results show that with the advance of working face, the fracture development of overlying strata and coal seams is larger and larger; the area of gob is gradually expanding and the transverse stress of overlying strata and coal seams is also expanding. Stress contour of overlying strata and coal seams at both ends of gob becomes denser and denser; the activity of the overlying strata and coal seams near the up-roadway side of the gob is violent. The pressure relief zone is formed in the upper part of the strata and the roof above the gob. Large inclination angle of coal seam results in larger supporting pressure in the underside of the gob and smaller supporting pressure in the upper side of the gob. Along the inclination direction of the working face, the pressure relief zone is mainly concentrated in the outlet roadway of the working face; the fracture development and strata separation are obvious, which offer good passage for gas flow and migration.