巷道围岩应力空间分布仿真分析

为得出巷道围岩应力空间分布特征,以圆形断面巷道为例,采用复变函数方法得出其应力解,并把映射空间解转化为巷道所在空间解后对巷道周围岩体应力场进行仿真分析,得出了巷道周围岩体应力场分布直观图,可方便直观的了解巷道围岩任意位置应力分布情况。并考虑不同半径、不同侧压系数对围岩应力场的影响,得出了：圆形巷道围岩应力峰值及其出现方向与半径无关;侧压系数小于1/3时,顶底板开始产生拉应力,大于3时两帮围岩开始产生拉应力;以及环向、径向、剪切应力及最大、最小应力的变化规律。     

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。     

拱形巷道电磁波传播近场区分界点的

为精确描述电磁波传播特性,运用Fresnel传播理论与几何知识,推导出收、发天线安装在不同位置时电磁波传播近场区分界点的计算公式,并在一般拱形巷道中进行仿真分析,得到最有利于电磁波传播时,天线的最佳位置。     

层状地层中矩形隧洞围岩应力及位移

为从理论上探析层状地层中隧洞围岩应力和位移求解问题,基于Покровский当层法理论,将层状地层转化为均质地层,再利用复变函数将坐标平面z上均质地层中矩形隧洞映射为复平面ζ的单位圆。首先,针对浅埋隧洞,阐述计算其应力及位移的方法;其次,针对深埋隧洞,通过求解解析函数Φ(ζ)和Ψ(ζ),得出层状地层中深埋矩形隧洞围岩应力,进而获得围岩应变和位移;最后,针对某具体矩形隧洞,借助MATLAB软件求解其解析函数Φ(ζ)和Ψ(ζ),研究围岩侧压力系数、边界力和隧洞高宽比等对隧洞围岩应力的影响。     

三心拱形巷道调节风窗面积计算公式的误差分析和校正

本文对调节风窗面积计算公式进行了分析。实验研究证明，利用现有理论调节风窗面积计算公式求算调节风窗面积时误差较大，而误差与巷道的几何形状等因素有关。当利用现有理论调节风窗面积计算公式求算梯形巷道调节风窗面积时的误差比三心拱形巷道时的误差大，根据实验研究结果，提出了在三心拱形巷道安设调节风窗时的理论公式校正系数和校正公式。     

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,...     

巷道围岩应力分布影响因素的研究

通过有限元计算和光弹模拟方法对影响巷道自稳结构形状的因素进行了探讨，分析了埋深，侧压秒数，巷道形状及裂隙等因素的变化对集中应力圈的作用，为合理选择巷道支护手段提供依据。     

不同断面形式深埋巷道围岩破坏数值模拟分析

以Ⅲ级围岩为例,利用有限差分软件FLAC对不同埋深情况下不同断面形式的巷道进行数值模拟,分析矩形、直墙拱形和圆形断面巷道围岩应力应变、围岩塑性区随埋深的变化规律及特点。结果表明：拱形断面巷道的围岩变形、围岩塑性区最小,尤其是顶板下沉量较矩形和圆形断面巷道的要小得多;圆形断面巷道围岩水平向位移最小;矩形断面巷道围岩应力及变形随埋深增加幅度都要大于拱形和圆形断面巷道。     

Deformation characteristics of surrounding rock of broken and soft rock roadway

A similar material model and a numerical simulation were constructed and are described herein. The deformation and failure of surrounding rock of broken and soft roadway are studied by using these models. The deformation of the roof and floor, the relative deformation of the two sides and the deformation of the deep surrounding rock are predicted using the model. Measurements in a working mine are compared to the results of the models. The results show that the surrounding rock shows clear rheological features under high stress conditions. Deformation is unequally distributed across the whole section. The surrounding rock exhibited three deformation stages: displacement caused by stress concentration, rheological displacement after the digging effects had stabilized and displacement caused by supporting pressure of the roadway. Floor heave was serious, accounting for 65% of the total deformation of the roof and floor. Floor heave is the main reason for failure of the surrounding rock. The reasons for deformation of the surrounding rock are discussed based on the similar material and numerical simulations.     

Rules of distribution in a plastic zone of rocks surrounding a roadway affected by tectonic stress

In order to study the rules of distribution in a plastic zone of rocks, surrounding a roadway, affected by tectonic stress, we first analyzed the mechanics of a roadway affected by tectonic stress and derived a theoretical formula for the plastic zone of rocks surrounding a roadway. We also analyzed the distribution characteristics of the plastic zone under different levels of tectonic stress, vertical pressure, cohesion and friction angle of the surrounding rock. Secondly, we used numerical simulation to analyze the range and shape features of the plastic zone of rocks surrounding the roadway, given different tectonic stress levels. Finally we used a rock drilling detector to carry out field measurements on the broken state of rock surrounding the roadway at the -700 substation and channels in the Xinzhuang mine of the Shenhuo mining area. Given the measured ground stress, we analyzed the relationship between tectonic stress and the distribution of this plastic zone. Our results show that the range of the plastic zone at the top and bottom of the roadway increases with an increase in tectonic stress and this increase is especially obvious at the roadway comer.     

高应力区域煤层巷道耦合支护数值模拟试验研究

为了研究耦合支护控制巷道变形的效果,根据耦合支护原理,使用FLAC3D有限差分数值模拟软件对某矿11010工作面回风巷在不同支护参数下巷道的顶板、底板、左帮和右帮深部基点位移与围岩最大位移进行了研究.结果表明,当支护体与围岩以及支护体之间在强度、刚度、结构满足耦合支护时,巷道深部基点位移与围岩最大位移均较小,且巷道处于稳定状态所需时间较短.通过工程实例进一步说明了耦合支护能有效地控制巷道围岩变形,维护巷道稳定.     

深部巷道围岩变形试验与数值模拟研究

为了研究深部软岩巷道的变形破坏特性,以淮南矿区某煤矿13-1煤回采巷道为例,在现场调查回采巷道工程概况的基础上,开展了室内深部回采巷道围岩变形特性相似模拟试验,并基于块体离散元法,建立了深部回采巷道围岩的数值模型,模拟了开挖过程中围岩的变形特性。相似模拟试验和数值模拟试验结果表明,深部巷道围岩的典型特征为:巷道底臌量两帮移近量顶板下沉量,巷道不同围岩受开挖扰动的位移影响范围不同,底板为3.5 m,顶板为2.45 m,两帮为5.5 m。     

围岩自承岩环的力学分析

根据力学分析和有限元计算,研究了围岩自承岩环的实质和效果。     

高应力回采巷道围岩变形特征及协调支护技术研究

为了研究高应力条件下回采巷道围岩变形特征,以石板沟煤业18002工作面回风巷为研究对象,根据该巷道工程地质特点,采用FLAC3D数值模拟软件,分析高应力工作面回风巷的变形影响因素,提出高预应力高强锚杆与锚索协调支护的总体思路．分析可知,围岩变形较大是多重原因综合作用的结果;采用高预应力高强锚杆．锚索协调支护对高应力巷道围岩变形控制效果明显;工业性试验结果表明,该技术能有效控制巷道围岩变形,为矿井安全生产创造条件,并取得较好的效果．     

复杂条件下巷道围岩破坏机理及支护方案研究

从许厂煤矿复杂的地质构造入手,分析了复杂地质构造所引起的高应力特征,并结合围岩物理力学特性对巷道围岩变形破坏特点及破坏机理进行了分析,提出了复杂地质构造及高应力条件下软岩巷道的安全支护技术措施.该结果对同类型工程的设计与施工具有重要的参考价值.     

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.     

Principle and practice of coupling support of double yielding shell of soft rock roadway under high stress

In order to ensure the safety and stability of the soft rock roadway under high stress, based on the characteristics of the surrounding rock deformation and failure, this paper presented the support technology “coupling support of double yielding shell”, then gave the design method of inner and outer shells and analyzed the principle and requirements of the support technology by taking the −850 m east belt roadway of Qujiang coal mine as the background. The field application results show that the support technology can control the soft rock roadway deformation better under high stress. The displacement between roadway sides was 851 mm, the displacement of the roof was 430 mm, and the displacement of the floor was 510 mm.