巷道组过断层围岩控制技术研究

以深井巷道组过特大型断层（落差大于100m）破碎带为工程背景,采用数值模拟的办法对比分析了正常地层和断层破碎带中巷道组围岩的力学特征以及相互影响;结合断层破碎带围岩的实际情况,建立了＂早预测、短进尺、弱爆破、强支护、紧封闭、勤量测、防突水＂的断层带施工技术和综合保障体系,形成超前物探、超前加固、微震开挖、分步动态支护等综合配套技术,保证了巷道的施工安全。     

浅埋偏压隧道洞口段围岩破坏机理

为了研究顺层岩质边坡下浅埋偏压隧道洞口段围岩破坏机理,以班丘隧道为例,根据现场地质调查结果,结合监测数据并利用数值模拟的方法分析了隧道洞口段围岩的破坏机制,提出了治理措施。结果表明:隧道浅埋侧拱肩处易出现拱形拉伸屈服塑性带,围岩易从此处开始破坏;围岩破坏是多种因素共同作用的结果,其中隧道偏压作用、岩体结构和降雨是造成隧道塌方和边坡滑坡的关键因素;隧道塌方模式为:掌子面上方岩体首先在重力作用下沿拱形屈服带形成拱形坍塌,然后在弯折内鼓作用下形成整体塌方,边坡滑坡的形式为坡体表面中风化页岩夹泥砂岩在坡体破坏的情况下发生顺层面的近平面滑移。     

侧爆作用下锚固洞室破坏形式及机理研究

为了进一步提高锚固洞室在侧爆作用下的抗爆能力,利用数值分析软件LS-DYNA3D程序,研究了在侧爆作用下的锚固洞室的破坏形式及机理.数值分析结果表明:压应力波一开始是以球形向四周传播的,当压应力波碰到洞室壁时,会在洞室壁表面产生拉应力波,并以椭圆形式向反向传播;在应力波整个传播过程中,由于反射拉伸可能会在洞室锚固区和非锚固区先后产生二次拉伸破坏,最后可能会由于洞室反射的拉伸波和地面反射拉伸波相遇共同作用,在离地面比较浅的地方产生拉伸破坏区.     

动静载叠加作用下深部巷道围岩变形破坏数值模拟研究

在深部煤矿开采中,巷道往往处于高地应力和强动力扰动的动静载叠加应力环境.由动静载叠加诱发的围岩严重变形破坏甚至灾变失稳现象屡见不鲜,严重威胁煤矿的安全高效开采.因此,对动静载叠加作用下巷道围岩变形破坏规律的研究具有非常重要的理论价值和工程意义.本文以数值模拟中非线性动力计算为手段,研究了不同初始应力场及不同动载条件对巷...     

确山煤田吴桂桥井田岩浆岩对煤层的影响破坏及接触变质带特征

吴桂桥井田喜山期岩浆活动剧烈，多以岩床形式顺层侵入煤层顶底板及煤层中间，对煤层赋存形式、结构、煤质产生较大破坏影响，变质作用以接触变质为主，煤类复杂。接触变质带可进一步划分为岩焦混杂带、天然焦带、焦化煤带、正常煤带。     

隧洞破碎带围岩失稳破坏模式及控制措施研究

为了解决在隧洞开挖过程中遇到节理带、断层等软弱破碎岩带时,发生大变形、塌方等围岩失稳破坏等问题,需提前或及时做好围岩支护措施,以确保洞室围岩的稳定及施工安全。本文以长河坝水电站泄洪洞工程为研究对象,通过对现场勘测资料、隧洞开挖施工方案及工程地质条件等的综合分析,确定了软弱破碎带围岩稳定的主要影响因素,提出了隧洞破碎带围岩的典型失稳破坏模式。针对隧洞破碎带处围岩的潜在失稳问题,综合采用超前支护、开挖后及时进行喷锚+钢支撑+锚筋束联合支护,并通过有限元手段对隧洞围岩支护方案的加固效果进行了分析。有限元计算结果表明,隧洞破碎带处经及时加强支护后,围岩变形得到有效地控制,避免了洞室围岩失稳破坏现象的发生;现场监测数据及实施效果也表明及时加强支护措施对围岩稳定控制的有效性。     

矩形和直墙拱断面围岩巷道破坏的数值模拟研究

通过对岩石破坏特性和机理的分析,得出岩石破坏的剪切强度与参数的数学关系。在此基础上建立围岩巷道的数值模型,模拟围岩巷道在矩形和直墙拱等断面条件下的破坏过程,得出巷道在不同侧压系数条件下的围岩破坏特征。结果表明:同一断面形状,当侧压系数较小时,破坏裂纹首先出现在两帮,随着荷载的增大,破坏裂纹由底部向顶部转移;另外基于矩形和直墙拱形断面巷道的数值模拟,得出了围岩巷道的破坏是一个渐进的过程,并伴随应力场而不断转移,且在相同侧压系数和外荷载条件下,矩形巷道破坏较为严重。分析矩形巷道和直墙拱巷道变形破坏过程,为合理寻求巷道设计和支护方法提供依据。     

动载扰动下巷道锚固承载结构稳定性影响因素分析

针对冲击地压巷道锚固承载结构破坏机理的复杂性和变形影响因素的多样性,基于响应面法试验设计和数据分析功能,采用有限差分数值软件动力模块,定量化研究围岩强度、震源距离、震源强度、原岩应力、支护强度等单一因素以及多因素交互作用对巷道锚固承载结构变形的影响规律.结果表明:单一因素和多因素交互作用对锚固承载结构变形都有显著影响,单因素影响程度依次为围岩强度>震源强度>震源距离>原岩应力>支护强度;通过增大震源传播距离、增加动载衰减系数、提高支护强度、增加围岩自承载能力、减小静载应力集中均可以有效降低冲击地压巷道锚固承载结构的变形量;多因素交互作用下巷道锚固承载结构的破坏模式可分为锚杆断裂型、锚固脱黏型、岩体主导型和复合型.针对不同的破坏模式,提出高冲击韧性锚杆全长预应力支护、"外锚内注"和"深部卸压-浅部强支-巷表防护"等控制技术.研究结果可为冲击地压巷道锚固承载结构稳定性控制提供理论依据.     

煤层底板破坏带电阻率法异常特征研究

我国大约60％的煤矿不同程度受到奥灰水的影响,研究承压水上采煤引起的底板破坏规律对于煤矿安全开采具有十分重要的意义。本文对电阻率法探测井下底板破坏带视电阻率异常特征进行研究。应用商业电法正反演软件EarthImager3D设计工作面推进过程中底板破坏带地质模型,利用混合边界条件下有限差分法进行正演模拟,并分析其异常特征和分布规律。正演结果表明,电阻率法能探测出底板破坏带异常,随着工作面的推进,在视电阻率剖面图上异常体的位置出现相应的移动。     

深部煤层瓦斯赋存规律及钻孔抽采有效半径研究

实测了新庄孜矿深部低透气性煤层的瓦斯压力、煤层透气性系数、瓦斯含量、瓦斯涌出衰减系数和自然排放半径等基础参数;在此基础上,数值模拟计算了钻孔抽采瓦斯的有效半径。研究结果表明,煤层的透气性是决定钻孔有效排采半径的主导因素。为提高低透气性煤层抽采瓦斯钻孔预抽消突效果,应积极采取措施提高煤层透气性系数。     

Deformation and failure characteristics of anchorage structure of surrounding rock in deep roadway

This paper investigated the stress evolution, displacement field, local deformation and its overall distribution, and failure characteristics of the anchorage structure of surrounding rock with different rockbolt spacing through the model experiments. The influences of the pre-tightening force and spacing of rockbolt on the support strength of the anchorage structure of surrounding rock were analyzed by the simulation using FLAC3D numerical software. The support scheme of the excavated roadway was then designed, and the effectiveness of this support scheme was further verified by the displacement measurement of the roadway. The results showed that the maximum displacement between the roof and floor of the west wing track roadway in Kouzidong coal mine, China is about 42 mm, and the maximum displacement between its both sides is about 72 mm, indicating that the support scheme proposed in this study can ensure the stability and safety of the excavated roadway.     

Failure mechanism and control technology of water-immersed roadway in high-stress and soft rock in a deep mine

Aiming at soft rock ground support issues under conditions of high stress and long-term water immersion, the ground failure mechanism is revealed by taking the deep-water sumps of Jiulong Mine as the engineering background and employing field investigation, tests of rock structure, mechanical properties and mineral composition. The main factors leading to the surrounding rock failure include the high and complex stress state of the water sumps, high-clay content and water-weakened rock, and the unreasonable support design. In this paper, the broken and fractured rock mass near roadway opening is considered as ground small-structure, and deep stable rock mass as ground large-structure. A support technology focusing on cutting off the water, strengthening the small structure of the rock and transferring the large structure of the rock is proposed. The proposed support technology of interconnecting the large and small structures, based on high-strength bolts, high-stiffness shotcrete layer plugging water,strengthening the small structure with deep-hole grouting and shallow-hole grouting, highpretensioned cables tensioned twice to make the large and small structures bearing the pressure evenly,channel-steel and high-pretensioned cables are used to control floor heave. The numerical simulation and field test show that this support system can control the rock deformation of the water sumps and provide technical support to similar roadway support designs.     

深部松散全煤巷道围岩变形特征分析

以新集矿区某具体巷道为例,根据工程实测结合数值模拟分析了深部开采松散全煤巷道两帮及顶板变形特点。结果表明:深部开采巷道两帮中部表现为显著的不稳定塑性变形;顶煤与直接顶结构面中部产生不稳定层间离层。分析结果可为深部开采全煤巷道合理支护选择提供依据。     

Failure mechanism of Mesozoic soft rock roadway in Shajihai coal mine and its surrounding rock control

In view of the buckling failure caused by large deformation of Mesozoic soft rock roadway in Shajihai mining area, such as serious roof fall, rib spalling, floor heave, etc., based on the detail site i...     

Surrounding rock control of gob-side entry driving with narrow coal pillar and roadway side sealing technology in Yangliu Coal Mine

Gob-side entry driving can increase coal recovery ratio, and it is implied in many coal mines. Based on geological condition of 10416 working face tailentry in Yangliu Coal Mine, the surrounding rock deformation characteristics of gob-side entry driving with narrow coal pillar is analysed, reasonable size of coal pillar and reasonable roadway excavation time after mining are achieved. Surrounding rock control technology and effective roadway side sealing technology are proposed and are taken into field practice. The results showed that a safer and more efficient mining of working face can be achieved. In addition, results of this paper also have important theoretical significance and valuable reference for surrounding rock control technology of gob-side entry driving with narrow coal pillar under special geological condition.     

Bolt-grouting combined support technology in deep soft rock roadway

Analyzing the mineral composition, mechanical properties and ground stress testing in surrounding rock,the study investigated the failure mechanism of deep soft rock roadway with high stress. The boltgrouting combined support system was proposed to prevent such failures. By means of FLAC3D numerical simulation and similar material simulation, the feasibility of the support design and the effectiveness of support parameters were discussed. According to the monitoring the surface and deep displacement in surrounding rock as well as bolt axial load, this paper analyzed the deformation of surrounding rock and the stress condition of the support structure. The monitor results were used to optimize the proposed support scheme. The results of field monitors demonstrate that the bolt-grouting combined support technology could improve the surround rock strength and bearing capacity of support structure, which controlled the great deformation failure and rheological property effectively in deep soft rock roadway with high stress. As a result, the long term stability and safety are guaranteed.     

深部软岩巷道围岩变形分析与控制

针对某深部软岩巷道支护困难问题,首先对围岩进行力学性能试验,然后利用有限元分析方法,在基于不同埋深软岩巷道围岩变形特征研究的基础上,从巷道开挖和围岩支护两方面对深部高地应力软岩巷道围岩变形与控制进行深入研究.结果表明:随软岩巷道埋深增大,巷道围岩变形呈线性增大趋势;在深部高地应力下掘进巷道时,全断面开挖法围岩变形最大,...     

大断面厚顶煤巷道围岩控制与支护参数优化

以山西大同同忻矿8104综放工作面回风巷(断面尺寸5.2 m×3.5 m)为工程研究背景,阐述了厚顶煤大断面巷道的围岩控制难题:顶煤裂隙发育、变形强烈、破坏范围大、易发生离层和冒顶等事故.结合现场地质生产条件,采用桁架锚索加强支护,并分析此支护系统的优越性:提供水平和竖直方向预紧力、变形闭锁、协同承载控制区域、锚固点稳.采用FLAC3D数值模拟计算了桁架锚索倾斜角度从10~40°变化过程中围岩变形规律:随着桁架锚索倾斜角度的增大,巷道围岩变形量先减小后增大,锚索倾斜20°时,巷道围岩变形量最小.表明回风巷受到采动影响后,顶底板最大移近量为395 mm,两帮最大移近量为263 mm.     

变宽沿空窄煤柱巷道围岩变形机理及控制技术研究

针对苏村煤业150101工作面回风巷掘进期间巷道围岩严重变形的情况,采用数值模拟、理论分析等方法对巷道变形破坏特征和破坏机理进行了分析。结果表明:护巷煤柱宽度不同,对沿空巷道围岩的应力分布及变形有较大影响,过大和过小的煤柱尺寸均不利于巷道围岩的稳定;苏村煤业150101工作面回风巷合理的煤柱宽度为5~6 m。在此基础上,结合合理的煤柱留设宽度,提出了变宽沿空窄煤柱巷道分段围岩稳定控制技术,对不同煤柱宽度进行分段,针对各个分段特征进行不同强度的支护。工业性试验结果表明,采用分段支护技术后,各分段沿空巷道围岩变形获得很好的控制效果,在类似地质条件下可以推广应用。     

Stability control of surrounding rocks for a coal roadway in a deep tectonic region简

In order to effectively control the deformation and failure of surrounding rocks in a coal roadway in a deep tectonic region, the deformation and failure mechanism and stability control mechanism were studied. With such methods as numerical simulation and field testing, the distribution law of the displacement, stress and plastic zone in the surrounding rocks was analyzed. The deformation and failure mechanisms of coal roadways in deep tectonic areas were revealed: under high tectonic stress, two sides will slide along the roof or floor; while the plastic zone of the two sides will extend along the roof or floor, leading to more serious deformation and failure in the corner of two sides and the bolt supporting the corners is readily cut off by the shear force or tension force. Aimed at controlling the large slippage deformation of the two sides, serious deformation and failure in the corners of the two sides and massive bolt breakage, a “controlling and yielding coupling support” control technology is proposed. Firstly, bolts which do not pass through the bedding plane should be used in the corners of the roadway, allowing the two sides to have some degree of sliding to achieve the purpose of “yielding” support, and which avoid breakage of the bolts in the corner. After yielding support, bolts in the corner of the roadway and which pass through the bedding plane should be used to control the deformation and failure of the coal in the corner. “Controlling and yielding coupling support” technology has been successfully applied in engineering practice, and the stability of deep coal roadway has been greatly improved.