高应力下巷道底鼓机理及其锚固技术研究.pdf

太原理工大学博士研究生学位论文 I 高应力下巷道底鼓机理及其锚固技术研究 摘 要 近些年，随着我国煤炭开采逐渐走向深部，地应力相应增大，而由于 巷道设计及布置过程中其深度、方位和倾角受到煤层赋存特征和矿井设计 的约束，导致布置在地下岩层内的巷道处于不利的复杂围岩应力环境之中， 巷道矿压显现明显，底鼓问题日趋严重，从而暴露出许多影响煤矿安全生 产的问题，严重影响了矿山的安全生产。因此，研究巷道底鼓的机理、防 治措施等问题，对于保障我国深部资源安全开采，提高开采作业人员安全 有着重大的理论意义和实际工程应用价值。 论文结合常村矿 S6 采区 1回风上山围岩条件、 地应力与岩石力学测试 结果，通过力学理论分析、相似模拟试验、数值模拟、现场工业试验等方 法进行了高应力下巷道底机理、防治措施等问题的研究。主要研究结论为 （1）以弹塑性力学理论为基础，运用广义平面应变问题和统一强度理 论对处于三向地应力环境下的开挖巷道围岩体进行弹塑性破坏力学解析， 推导出了三向地应力环境下巷道底板围岩弹塑性区应力与塑性破碎范围的 方程，同时借助力学解析结论，结合常村矿区地应力原位探测分析结果， 运用算例对巷道底板围岩的稳定性进行了分析，揭示了巷道自身条件、轴 向主应力等对底板围岩稳定性的影响， 并计算得出了常村矿 S6 采区 1回风 上山底板围岩的塑性破碎区范围及各应力值，为后面的底鼓治理技术研究 提供了可靠的力学理论基础； （2）以矩形巷道底板锚固围岩体为研究对象，根据力学理论中梁的有 太原理工大学博士研究生学位论文 II 关假定建立了底板水平梁的力学分析模型，并对其在无支护及锚杆不同支 护条件下进行力学解析，揭示了锚杆控制底鼓的力学机理，同时借助其力 学解析结论对影响巷道底鼓的诸因素进行算例分析，得知控制巷道底鼓的 关键性问题； （3）结合已获取的现场巷道围岩资料，以常村矿 S6 采区 1回风上山 为工程背景进行相似模拟试验，分析了巷道底板在无支护和采取底锚措施 后底板围岩应力分布和变形破坏特征，揭示了巷道产生底鼓的直接原因是 由于底板在综合应力作用下一直处于高应力状态，且在水平应力的作用下， 两底角的围岩体相对向巷内挤压错动，错动带与底板成 35左右，同时对无 支护与采取底锚措施后的模拟结果、相似模拟结果与力学理论解析结果进 了行对比分析， 得知采取底锚措施后底鼓量比无支护减少了近 49.6， 并通 过综合分析，认为力学理论解析结果与相似模拟试验结果基本相接近； （4）提出了一种治理底鼓的混凝土反拱组合结构，同时根据力学理论 及有关假定，建立了锚杆-混凝土反拱组合结构底鼓控制的力学模型，并对 其进行了力学解析，揭示了其控制底鼓的力学机理，随后借助力学解析结 论，结合常村矿 S6 采区 1回风上山具体情况，运用算例分析了锚杆-混凝 土反拱组合结构的稳定性，并建立了锚杆-混凝土反拱组合结构稳定性条件 方程； （5）结合常村矿 S6 采区 1回风上山具体情况，提出了常村矿 S6 采区 1上山底鼓治理对策与设计支护方案，通过对锚杆-混凝土反拱组合结构稳 定性判别，证实了混凝土反拱组合结构稳定且参数设计合理，通过对支护 方案数值模拟分析，认为支护结构未超过极限载荷，且底鼓量为 135mm， 太原理工大学博士研究生学位论文 III 通过现场工业试验反馈的底锚巷道底鼓量为 182～194mm， 与相似模拟试验 结果（243.93mm）和力学解析结果（274mm）基本接近，锚杆-混凝土反拱 组合结构控制底鼓的底鼓量为 135142mm，与力学解析结果（106.7mm） 和数值模拟结果（135mm）也基本吻合。同时由工业试验可知，采取锚杆- 混凝土反拱组合结构控制底鼓时，其底鼓量减少了近 73，且底鼓支护结 构稳定，完成了对 S6 采区 1回风上山底鼓治理和巷道围岩控制的最终目 的。 关键词高应力，巷道底鼓，力学解析，底鼓治理，锚杆-混凝土反拱 组合结构 太原理工大学博士研究生学位论文 IV 太原理工大学博士研究生学位论文 V STUDY ON FLOOR HEAVE MECHANICSAND BOLTING TECHNOLOGY FOR ROADWAYS IN HIGH STRESS ABSTRACT In resent years, as the coal mining moving deeper layer, the ground stress increases correspondingly, with the occurrence characteristics of coal seam of the roadways depth, azimuth and dip during roadway design and layout, also with the restriction of the mine design, which leads to the roadway in the unfavorable complex surrounding rock stress environment, the strata pressure behavior of roadway and the problem of floor heave of roadway became worse, thereby many factors that may affect the safety in production of coal mine are exposed, the safety production of mine have been seriously threatened. Therefore, research on the mechanism of roadway floor heave and the prevention measures has the theoretical and pratical significance for not only the guarantee of safety production of deep mining, but also the enhancement of underground mining operation safety. Based on the test results of surrounding rock condition, in-situ stress and rock mechanics of 1roadway in S6 mining area of Changcun mine, the mechanism and control measures of roadway floor heave in high stress have been carried out through the mechanics theoretical analysis, similar simulation test,numerical simulation, field industrial test etc. The main conclusions of thesis 太原理工大学博士研究生学位论文 VI are listed as follows 1 Based on the theory of elastic mechanics, the elastoplastic damage mechanics analysis of the surrounding rock body of the excavated roadway under the three directional geostress is carried out by using the knowledge of generalized plan strain and unified strength theory, the equations of elastic and plastic zone and the plastic fracture range of surrounding rock of roadway floor under three directional geostress is derived, at the same time, by means of mechanical analysis conclusion, combined with the analysis of the results of the stress of Changcun mining area in-situ detection, the stability of surrounding rock of roadway floor were analyzed by using a numerical example, reveal the influence of roadway condition, axial principal stress etc on the stability of the roadway floor surrounding rock, and the range of plastic crushing zone and stress value of 1roadway in S6 mining area of Changcun mine is obtained, that provides a reliable theoretical basis for the research of the roadway floor heave control technology; 2 The surrounding rock body of rectangular roadway is studied as the object, A mechanical analysis model of roadway floor as horizontal beam plate is estabilished according to the assumption of beam in mechanics theory, and the mechanical analysis is carried out on the condition of no support and bolt support, reveal the mechanics mechanism of anchor rod to control the floor heave,simultaneously, by means of the analysis of the mechanical analysis results on the factors affecting the floor heave of the roadway, the key problems of controlling the floor heave of the roadway are obtained; 太原理工大学博士研究生学位论文 VII 3According to the field data of surrounding rock acquired in the roadway, 1roadway in S6 mining area of Changcun mine as the engineering background, the similar sumulation tests were taken to analyze the stress distribution and the deation and failure characteristics of surrounding rock of roadway floor on the condition that the roadway floor is not supported or adopted bottom anchor, which reveals that the direct causes of roadway floor heave is the floor in the comprehensive stress that has been in a high stress state, and affected by horizontal stress, the floor rock mass of its two base angle was extruded and dislocated, fault zone and the floor is about into 35 degrees, at the same time, by compared analysising the roadway floor is not supported or adopted bottom anchor, similar simulatuion test results and mechanics theory analysis results, the bottom anchor measures taken compared to no support, the amount of floor heave decreased by nearly 49.6, after comprehensive analysis, it is concluded that similar simulatuion test results and mechanics theory analysis results is basically close; 4 An antiarch combined structure of concrete is put forward to control floor heave, based on the mechanics theory and assumption, the mechanical model of the bolt and concrete antiarch combined structure is established, and its mechanical mechanism is studied, simultaneously, by means of mechanical analysis conclusion, combined with the specific circumstances of 1roadway in S6 mining area of Changcun mine, the stability of the bolt and concrete antiarch combined structure is analyzed by the analysis example, and the stability conditions equation of the bolt and concrete antiarch combined structure is 太原理工大学博士研究生学位论文 VIII estabilished; 5According to the specific circumstances of 1roadway in S6 mining area of Changcun mine, the floor heave control countermeasures and design of supporting scheme is put forword, based on the bolt and concrete antiarch combined structure stability criterion, the concrete antiarch combined struture is confirmed stable and its design parameters are reasonale, meet the safety requirements, the supporting scheme is analyzed by numerical simulation, it is shown that the supporting structure is not exceeding the limit load, and the amount of floor heave is 135mm, field industrial experiment shows that the bottom anchor actual floor heave is 182～194mm, the field test results are close to the results of similar simulation test243.93mm and mechanical analysis274 mm, the actual floor heave is 135 ～ 142mm by anchor concrete antiarch combined structure to controlling floor heave,the field test results are close to the results of mechanical analysis106.7mm and similar simulation test135m m。 At the same time, we find that the floor heaves is reduced nearly 73 by the bolt and concrete antiarch combined structure to controlling roadway floor, and supporting structure is stable, the control of floor heave of 1roadway in S6 mining area is completed. KEY WORDS high stress; roadway floor heave; mechanical analysis; floor heave control; concrete antiarch composite structure 太原理工大学博士研究生学位论文 1 目 录 摘 要...........................................................................................................................................I ABSTRACT...............................................................................................................................V 目 录...........................................................................................................................................1 第一章绪论.....................................................................................................................1 1.1 选题的背景及意义.......................................................................................................1 1.2 国内外研究现状与综述...............................................................................................2 1.2.1 巷道底鼓机理.....................................................................................................2 1.2.2 巷道底鼓的防治措施.........................................................................................4 1.2.3 存在的问题.........................................................................................................7 1.3 论文研究内容、方法与技术线路...............................................................................8 1.3.1 研究内容与方法.................................................................................................8 1.3.2 技术路线.............................................................................................................9 第二章 三向地应力环境下巷道底板围岩弹塑性力学解析与稳定性分析.........................11 2.1 三向地应力作用下巷道围岩弹性区应力解析.........................................................11 2.1.1 地应力环境与巷道的空间关系.......................................................................11 2.1.2 基于广义平面问题建立巷道围岩力学方程...................................................13 2.1.3 巷道围岩弹性区应力方程求解.......................................................................15 2.2 三向地应力作用下巷道围岩塑性破碎区范围与应力解析.....................................17 2.2.1 基于统一强度理论求解巷道围岩塑性破碎区应力方程...............................18 2.2.2 巷道围岩塑性破碎区范围求解.......................................................................21 2.3 巷道底板围岩稳定性算例分析.................................................................................24 2.3.1 地应力环境对巷道底板围岩稳定性影响分析...............................................24 2.3.2 轴向主应力对巷道底板围岩稳定性影响分析...............................................30 2.3.3 巷道自身条件对底板围岩稳定性影响分析...................................................31 2.4 常村矿 S6 采区 1回风上山底板围岩塑性破坏范围与应力解析..........................33 2.5 本章小结.....................................................................................................................35 第三章 高应力下锚杆控制巷道底鼓的力学解析与底鼓影响因素分析.............................37 3.1 锚杆控制巷道底鼓的力学解析.................................................................................37 3.1.1 锚杆支护下底板水平梁力学模型的建立.......................................................37 3.1.2 无支护下底板水平梁稳定性力学解析...........................................................38 3.1.3 锚杆支护下底板水平梁稳定性力学解析.......................................................40 3.1.4 等间距锚杆支护下底板水平梁稳定性力学解析...........................................43 3.2 巷道底鼓主要影响因素算例分析.............................................................................47 3.2.1 水平应力对巷道底鼓的影响...........................................................................47 3.2.2 垂直应力对巷道底鼓的影响...........................................................................48 3.2.3 底板围岩弹性模量对巷道底鼓的影响...........................................................49 3.2.4 底板跨度对巷道底鼓的影响...........................................................................50 太原理工大学博士研究生学位论文 2 3.2.5 底板锚固深度对巷道底鼓的影响...................................................................51 3.2.6 底板锚杆锚固强度对巷道底鼓的影响...........................................................52 3.2.7 底板锚杆布置密度对巷道底鼓的影响...........................................................53 3.3 本章小结.....................................................................................................................54 第四章 高应力下巷道底鼓特性相似模拟试验研究.............................................................59 4.1 相似模拟理论.............................................................................................................59 4.2 试验装置简介.............................................................................................................59 4.3 相似模拟试验方案设计.............................................................................................61 4.3.1 试验原型条件...................................................................................................61 4.3.2 相似条件的确定...............................................................................................61 4.3.3 相似材料的选择及配比...................................................................................61 4.3.4 应力和位移测点的布置...................................................................................62 4.3.5 加载与开挖.......................................................................................................63 4.3.6 巷道采取底锚措施的模拟方案.......................................................................64 4.4 巷道无支护下底板围岩应力分布特征.....................................................................65 4.4.1 巷道底角应力分布特征...................................................................................65 4.4.2 巷道底板应力分布特征...................................................................................66 4.5 巷道无支护下底板围岩变形破坏特征分析.............................................................67 4.6 巷道采取底锚措施后底板围岩应力分布特征.........................................................69 4.6.1 巷道底角应力分布特征...................................................................................69 4.6.2 巷道底板应力分布特征...................................................................................70 4.7 巷道采取底锚措施后底板围岩变形破坏特征分析.................................................71 4.8 本章小结.....................................................................................................................73 第五章 高应力下锚杆-混凝土反拱组合结构底鼓控制力学解析及其稳定性分析...........75 5.1 锚杆-混凝土反拱组合结构底鼓治理技术方案.......................................................75 5.2 锚杆-混凝土反拱组合结构底鼓控制力学模型的建立与力学解析.......................77 5.2.1 锚杆-混凝土反拱组合结构底鼓控制力学模型建立.....................................77 5.2.2 锚杆-混凝土反拱组合结构底鼓控制力学解析.............................................78 5.3 锚杆-混凝土反拱组合结构稳定性分析及其力学判据...........................................84 5.3.1 混凝土反拱结构参数对锚杆-混凝土反拱组合结构及底板稳定性分析.....84 5.3.2 锚杆-混凝土反拱组合结构稳定性力学判据.................................................89 5.4 本章小结.....................................................................................................................91 第六章 高应力下巷道底鼓控制工程应用.............................................................................95 6.1 常村矿 S6 采区 1回风上山围岩控制与底鼓治理对策..........................................95 6.2 常村矿 S6 采区 1回风上山围岩控制与底鼓治理支护方案设计..........................96 6.3 锚杆-混凝土反拱组合结构稳定性判别...................................................................99 6.4 支护方案数值模拟分析.............................................................................................99 6.4.1 数值模拟的目的............................................................