基于组合赋权法和云模型的磷矿地压稳定性评价

磷矿开采过程中诱发的地压已严重影响了矿山安全生产,开展磷矿地压稳定评价是保障安全生产的重要内容之一。以位于湖北宜昌的神龙磷矿典型矿区为研究对象,首先分析总结了神龙磷矿矿区的岩体结构特征和地压危害形式,并在此基础上构建稳定性评价指标体系,接着利用组合赋权法将层次分析法和基于指标相关性的指标权重确定法有机结合获得最优权重,再结合云模型计算评价指标的数字特征值,最后根据稳定性分级评价集得到稳定性评价结果。完成了4个分区的地压稳定性评价,通过进一步现场核对,评价结果与实际观测结果一致,说明提出的评价指标和评价模型在磷矿地压评价中有较好的适用性,对指导磷矿安全生产具有参考价值。     

采动影响下断层活化规律的数值模拟研究

以采用库仑剪切模型的接触面单元代表断层两盘的接触状态,模拟工作面从断层上盘和下盘向断层方向逐步回采的过程,研究断层接触面上法向应力和剪切应力的时空演化规律、断层上下盘的运动规律.模拟发现:在工作面回采的过程中,断层带上的应力分布具有明显的时空特征,断层上法向应力和剪切应力对采动影响具有不同的敏感性,断层法向应力的变化总是早于剪切应力;工作面距离断层越近,断层越易于活化,上盘推进时,断层影响范围约为断层前方60m,下盘推进时,工作面与断层距离小于20m时断层最易出现活化;不同的回采方式会引起断层不同的活化危险性,相比上盘开采,下盘开采时采动对断层的影响范围更为集中,活化危险性更高.     

不同采矿方法下采场稳定性数值分析

采用数值分析软件ANSYS对某矿体典型采场顶板与间柱的稳定性及其对采场围岩力学状态的影响进行数值模拟分析,矿山采用浅孔留矿法和分段凿岩阶段矿房法对于不同产状的矿体进行开采,对不同采矿方法下典型采场结构模型的模拟结果进行了分析,根据分析结果,结合矿山生产现状对目前采矿方案提出合理化建议,以便更确切地掌握不同采场地压的发展变化规律,有效地实施地压管理,实现安全高效开采。     

煤岩体拉伸铁稳破坏的机理及数值模拟

本文分析了拉伸失稳破坏的机理，并建立了拉伸失稳破坏的判别准则及对拉伸失稳破坏进行数值模拟的方法。最后，本文对工程实例进行了数值模拟计算和分析。     

深井矿山联合开采交错区地压显现时空规律研究

为了研究矿山联合开采的地压显现规律,以夏甸金矿为例,其矿体中浅部采用崩落法开采,跨度超过300 m,而两翼采用充填法开采.采用数值模拟与现场监测方法,综合分析了深部联合开采交错区的应力、位移等时空规律.数值模拟结果表明：无底柱分段崩落法与上向水平分层充填法联合开采时,崩落采空区下方应力集中数值较大,矿体两翼略小,交错区应力值最高.地压动态监测发现,无底柱分段崩落法区的顶板沉降位移与巷道水平收敛位移普遍大于上向分层充填法,但围岩二次应力的变化要略小于上向分层充填法,联合开采区域在整体上处于稳定状态.研究实现了多参量联合动态监测,为深部开采过程中地压显现的有效监测预警提供了有效手段,具有良好的推广示范效应.     

宜昌磷矿工艺矿相学研究

对宜昌磷矿进行了工艺矿物学研究,测定出了矿石的化学成分、各组分的赋存状态、矿物的嵌布特征和单体解离度.研究表明宜昌磷矿中含P2O5、CaO、SiO2、Al2O3、MgO、Fe2O3、K2O、F、S、Na2O等化学成分,胶磷矿、碳酸盐矿物、石英质矿物和粘土质矿物是其主要矿物单体,它们总质量分数达到98.2%.有96%的胶磷矿嵌布粒度和93%的碳酸盐矿物嵌布粒度大于0.0784 mm,而且它们的单体解离度在三个粒级均大于90%,属中粒嵌布.     

宜昌中低品位磷矿工艺流程试验研究

对宜昌丁东磷矿进行重介质选矿+正—反浮选试验与原矿直接进行正—反浮选试验研究,结果表明,分离密度为2.70时,只抛去17.35%的尾矿,量太少,仍需与正—反浮选联合使用,才能保证精矿品位P2O530%以上,回收率80%以上,MgO低于0.8%的磷精矿指标;而原矿直接进行正—反浮选流程(一粗一精一扫正浮选和一粗一扫反浮选),在不加温条件下,原矿P2O516.83%时,闭路试验可获得P2O531.49%,回收率83.75%,MgO 0.52%,选矿比为2.28的优良指标.可见,宜昌磷矿更适于采用直接正—反浮选流程,从而保证资源的经济、合理、有效利用.     

单侧采空工作面矿震活动规律与冲击地压相关性分析

以某矿井21103工作面生产地质条件为背景,研究了单侧采空工作面矿震活动规律、冲击地压显现特征以及矿震活动与冲击地压时间域的相关性.结果表明:针对单侧采空工作面,邻空侧巷道冲击显现可划分为邻空侧巷道帮鼓明显,顶底板破坏不明显;顶底板破坏明显,巷道帮鼓不明显;巷道帮鼓、顶底板破坏均明显三类.工作面矿震以低能级矿震为主,能...     

不等长工作面覆岩破坏规律的数值模拟分析

针对不等长工作面煤层开采日渐增多的现状,采用数值模拟与理论分析相结合的方法,对采场覆岩的破坏特征及支承压力的分布状态进行系统研究,并相应模拟出工作面前方应力场与位移场的演化规律。结果表明：工作面自开切眼开始向前推移,推进到工作面“见方”期或斜长的整数倍位置时,顶板活动剧烈,覆岩空间结构发生新旧更替,形成了“0”型破断区;不等长工作面推进过程中岩层运移极不规则,推进距离在衔接面前后20～30m的范围内,应力波动较大,数值变化明显;回采期间支承压力对覆岩活动产生了重要影响,其大小约为水平应力的1．5～2倍;就采动过程中竖向位移的变化而言,巷帮移近量远大于顶底板变形量,故工程实践中应特别注意对巷帮及顶板的加固和维护。     

放顶煤采场矿压显现规律的研究

通过对放顶煤开采方法的实验室相似材料模拟研究和现场矿压实测资料的分析,文章提出了放顶煤采场上覆岩层移动规律和采场矿压显现特征,同时还建立了放顶煤采场矿压结构模型。     

Regularity and prediction of ground pressure in Haigou Gold Mine

Previous mining excavation in upper sublevels left several mined-out areas in Haigou gold mine. To ensure safety of the main and auxiliary shafts and mining production in deeper sublevels, systematical studies on regularity, prediction, and control of ground pressure in the mine were carded out. Through 3D-numerical modeling and in-situ monitoring of acoustic emission, pressure and displacement, the ground pressure activity and the stability status of surrounding rock masses and the two shafts were assessed.Based on in-situ monitoring practice in Haigou mine, 4 modes to judge rock stability according to the monitoring information of acoustic emission, pressure, and displacement were presented.     

宜昌磷矿重介质选矿工艺矿物学

为探究宜昌磷矿中主要组分的赋存状态和矿物条带的工艺性能以确定其重介质选矿工艺的可行性,对宜昌磷矿进行了工艺矿物学研究.首先使用化学成分分析和荧光成分分析对矿石中各条带的矿物成分和化学成分进行测定,再对矿石中各条带解离性进行测定,并用重液浮沉法对各条带的比重分布进行测试.结果表明,宜昌磷矿石中98.98％的五氧化二磷分布在磷块岩条带中,同时磷块岩条带含有2.29％倍半氧化物,磷块岩条带重量百分比为81.32％;磷块岩条带和脉石条带宽度大且各条带之间存在硬度差别,磷块岩条带易于单体解离;在密度范围2.7～2.9,磷块岩条带与粘土质条带可通过重介质选矿选别.因此宜昌磷矿采用重介质选矿,可先选别出矿石中的磷块岩条带,然后再处理倍半氧化物,可获得合乎要求的优质磷精矿.     

深部开采冲击地压发生条件及预测和防治

本文简要阐述了深部开采冲击地压发生的条件及影响因素,分析了冲击地压发生地规律和破坏形式,提出了煤体冲击地压的预测技术,包括围岩变形监测法、钻屑法、电磁辐射探测法、微地震监测法四种方法,并针对冲击地压提出了具体的防治措施,包括诱发爆破、卸载爆破、宽巷掘进、卸压钻孔等技术手段。由于冲击地压随着采深增加越来越成为主要的矿压灾害,只有采用先进的预测方法和防治措施的综合防治体系才能保证生产安全。     

条并卷联合机棉卷加压机构对比及压力分析

为了使条并卷联合机的棉卷成型良好,对3种棉卷加压机构进行了分析对比.分析表明,传统加压机构存在爬行现象的缺陷,齿轮齿条式加压机构及气缸式加压机构消除了爬行现象,机件动作准确,加压稳定,但气缸式加压机构对气体的压力及其变化规律的要求较高.对齿轮齿条式加压机构进行了力学分析,编制了计算机程序,得出了保持棉卷成型良好的压力曲线及方程,将压力方程输入可编程控制器PLC,可对条并卷联合机的棉卷加压进行在线控制.     

黄土高填方场地孔隙水压力的变化规律

孔隙水压力是评价黄土高填方场地变形与稳定的重要参数.为探讨沟谷地形中黄土高填方场地孔隙水压力增长和消散规律,对陕北某黄土高填方工程进行了施工期和工后期的孔隙水压力监测和分析.结果表明:在分析超静孔隙水压力的增长和消散规律时,须扣除因土层压缩和地下水位变化而引起的静水压力变化值;孔隙水压力的增长和消散主要受地下水位和填土...     

Seismological method for prediction of areal rockbursts in deep mine with seismic source mechanism and unstable failure theory

The research on the rock burst prediction was made on the basis of seismology, rock mechanics and the data from Dongguashan Copper Mine (DCM), the deepest metal mine in China. The seismic responses to mining in DCM were investigated through the analyses of the spatio-temporal distribution of hypocenters, apparent stress and displacement of seismic events, and the process of the generation of hazardous seismicity in DCM was studied in the framework of the theory of asperity in the seismic source mechanism. A method of locating areas with hazardous seismicity and a conceptual model of hazardous seismic nucleation in DCM were proposed. A criterion of rockburst prediction was analyzed theoretically in the framework of unstable failure theories, and consequently, the rate of change in the ratio of the seismic stiffness of rock in a seismic nucleation area to that in surrounding area, dS/dt, is defined as an index of the rockburst prediction. The possibility of a rockburst will increase if dS/dt>0, and the possibility of rock burst will decrease if dS/dt<0. The correctness of these methods is demonstrated by analyses of rock failure cases in DCM.     

The friction and wear characteristics and lubrication mechanism of imidazole phosphate ionic liquid

Several imidazole phosphate ionic liquids with varying carbon chain length have been synthesized at room temperature. Corrosion characteristics and tribological properties of these synthesized ionic liquids were studied using four-ball friction and wear testing machine. Its lubrication mechanism was also investigated by means of electron microscopy and X-ray photoelectron spectroscopy. The experimental results showed that no corrosion was generated when the imidazole phosphate ionic liquid was applied to steel-steel pair. Meanwhile, the imidazole phosphate showed excellent anti-wear and lubricating performances, its frictional performance was related to the polarity of ionic liquids. It is suggested that the ionic liquids react with friction surface to form a protective film of iron phosphate and result in reduction in friction and wear. Supported by the National Natural Science Foundation of China (Grant Nos. 50721062 and 20533080) and the National Basic Research Program of China (973 Program) (Grant No. 2007CB607606)     

Dust removal efficiency of high pressure atomization in underground coal mine

To master theoretical calculation for dust removal efficiency of high pressure atomization in an underground coal mine, the corresponding atomization characteristics and dust removal efficiency were both comprehensively studied in theory by virtue of related theories of hydromechanics and aerosol.According to actual measurements of flow coefficients and atomization angles of X-type swirl nozzle,computational formula was derived for atomized particle sizes of such a nozzle in conjunction with relevant empirical equation. Moreover, a mathematical model for applying high pressure atomization to dust removal in underground coal mine was also established to deduce theoretical computation formula of fractional efficiency. Then, Matlab was adopted to portray the relation curve between fractional efficiency and influence factors. In addition, a theoretical formula was also set up for removal efficiency of respirable dust and total coal dust based on dust size and frequency distribution equations. In the end,impacts of dust characteristic parameters on various dust removal efficiencies were analyzed.     

高水平地应力下自然崩落法底部结构灾变机理

为研究高水平地应力下自然崩落法拉底推进过程中底部结构应力演化规律,揭示底部结构地压灾害特征产生的机理,从而指导高水平地应力下自然崩落法生产. 根据矿山实际工程参数和物理参数,采用有限差分软件FLAC3D建立了数值仿真模型,计算采用Mohr-Coulomb破坏准则.模拟过程按照后退式拉底方式,先形成底部结构,然后拉底分3步进行,分别监测并分析了每步拉底之后的底部结构应力状态,并与现场地压灾害发生实际情况进行了对比,研究结果与现场地压灾害演变规律具有一致性. 结果表明:随着拉底爆破的推进,推进线前方的底部结构逐渐产生压应力集中,当压应力增大到超过岩体剪切破坏条件,就会发生地压破坏现象；位于拉底层下方的底部结构呈现拉应力集中,当拉应力增大到超过岩体拉伸破坏条件,就会再次发生地压破坏现象；在高水平地应力下,自然崩落法底部结构会呈现“先受压,后受拉”应力规律,随着拉底面积的增加,压应力和拉应力集中程度越来越明显,在实际生产中呈现底部结构反复来压的现象.