【作者】 王猛；

【导师】 题正义；

【作者基本信息】 辽宁工程技术大学 ， 采矿工程， 2010， 博士

【摘要】 随着深部煤炭资源的不断开发以及深部矿井的建设,高地应力问题的出现成为危及井巷工程围岩体安全的主导因素,浅部开采的巷道支护理论及技术在深部开采巷道围岩受高应力状态下很难适应巷道围岩的稳定及支护问题,给巷道围岩稳定性及井巷施工安全提出了新的研究课题。因此,对深部开采巷道围岩变形破坏特征以及对其支护加固技术等问题的研究显得尤为重要和迫切。以此为出发点,本文结合国家自然科学基金面上项目“深部巷道围岩变形、破坏全过程及稳定控制机理”(50674083)、山东郓城煤矿委托项目“深井高应力巷道围岩破坏机理与控制技术的研究”及山东郓城煤矿埋深900m的井下掘进巷道为工程背景,以采矿学、岩体力学、弹塑性力学、断裂力学等理论为基础,通过相似材料模拟、理论分析、数值模拟、现场实测及工程实践等手段对煤矿深部开采巷道围岩变形破坏特征开展了试验研究,提出了适合于煤矿深部开采巷道围岩支护技术和方法。本文的研究内容主要包括以下几个方面:利用大尺度三维地下工程综合模拟实验系统对煤矿深部开采条件下的巷道开展了“先加载,后开挖”的相似材料模拟试验。采用自行设计制作的气压芯模支护结构、可缩支护结构及无支护模拟了不同支护方式下的巷道围岩的破坏特征,利用主方向应变传感器获得了试验加载过程中的荷载传递规律和巷道围岩周围主应力大小及其方向的演化规律,采用位移计获得了有支护和无支护巷道围岩的收敛变形规律;分析了相似材料模拟试验获得的深部高水平应力条件下不同支护形式的巷道围岩破坏特征,研究了巷道围岩内部和掘工作面的主应力大小及方向演化与巷道围岩变形破坏的关系,通过巷道围岩表面位移的收敛规律对不同支护形式的支护作用进行了分析;根据相似材料模拟试验中深部开采巷道围岩的变形破坏特征及破坏区的范围,并采用钻孔摄像测量系统对郓城煤矿已掘巷道的变形破坏特征进行了观测,结果表明与相似材料模拟所获得的现象是一致的。采用能量分析方法研究了巷道围岩表面初始裂缝的产生原因,结合断裂力学相关理论对巷道开挖后围岩内裂缝的扩展、贯通过程进行了分析。首次发现了深部开采的巷道围岩在压剪作用下会随着主应力大小及方向的不断演化而逐渐向围岩深处扩展破坏,最终在压应力集中区域形成多条交错的剪切滑移裂缝,使巷道产生破坏失稳。同时对形成的剪切滑移裂缝的形态进行了数学描述;根据深部开采巷道围岩变形破坏特征的理论分析,运用数值模拟软件FLAC3D对相似材料模拟试验进行了数值模拟验证,分析了深部开采条件下不同侧压系数、不同残余强度对巷道围岩破坏区大小、形状的影响;根据相似材料模拟试验、理论分析、数值模拟及现场实测结果,针对深部巷道围岩稳定性控制进行了理论分析,并提出“适度让压、及时应力恢复,改善受力状态、固结修复,加固围岩、加强关键部位支护”的控制方法;针对郓城煤矿深部开采的巷道支护存在的问题,根据实测结果及理论分析结果,有针对性的进行了支护方案设计并进行了现场工程试验。现场实测表明,采用的的支护方案有效的控制了巷道围岩的剧烈变形破坏,巷道使用安全性大大提高,验证了支护方案的可行性。更多还原

【Abstract】 With the continuous development of the deep coal resources and the building of the deep mines, the occurrence of the high stress problems becomes the dominating factor endangering the roadway rocks stability. Thus, the roadway supporting theory and technology for the shallow mining can hardly adapt the problems on the roadway rocks stability and supporting in the state of the high stress, which makes a new research topic on the roadway rocks stability and the safety of the roadway projects be put forward. Therefore, it is particularly important and urgent to study such problems as the deformation and damage mechanism of surrounding rocks and the support and reinforcement technique of the roadways. From this starting-point and combined with the National Natural Science Foundation Item“Deformation and damage process of surrounding rocks of deep roadway and mechanism of stability control”(50674083) and the entrusted project“Damage mechanism and control technique of surrounding rocks of deep roadway”from Shandong Yuncheng Mine, based on mining science, rock mass mechanics, elastic-plastic mechanics and fracture mechanics, the deformation and damage mechanism of the surrounding rocks of the deep roadway in the coal mines was studied with the similar material simulation, theory analysis, numerical simulation, site observation and engineering practice, then the support technique and method of the roadway in the state of the high stress is put forward. The major contents in this paper are as follows:The similar material simulation of first load and then excavation is carried out for the roadway in the state of the high stress with the test platform system for simulating the big scale 3D underground engineering. The failure characteristics of the roadway rocks are simulated in different support ways such as the pneumatic mandrel supporting structure self-designed and built, the collapsible supporting structure and nothing supported, the load transfer mechanism and the evolution rules of the principal stress during being loaded are gained with the main direction strain sensors and the convergence deformation laws are obtained with the displacement gauges.The failure characteristics of the roadway rocks given by the similar material simulation under the condition of high stress in different support ways are analyzed, the relationship between the evolution rules of the principal stress in the roadway rocks or at the driving face and the roadway deformation is studied and the affects of different support ways are analyzed though the convergence laws of the surface displacement of the roadway.Based on the deformation and failure characteristics and the broken range of the roadway rocks under the condition of high stress as well as the measured results of the deformation and failure of the excavated roadways actually by using the sight instrument, it can be shown that the measured results are in accord with that of the similar material simulation. The reason for the occurrence of the initial cracks on the surface of the roadway rocks is studied with the energy analysis method, then, combined with the fracture mechanics relevance theory, the expanding and linking process in the roadway rocks is analyzed. With the continuous evolution of the principle stress, the deep roadway rocks under the condition of high stress fails into the inside by the compressive-shear action. Finally, a few shearing and slippage cracks take place in the area of compressive stress concentration, which make the roadway instable. At the same time, the mathematical description of the shapes of the cracks is developed.Based on the analysis and research of the deformation and failure mechanism of the roadway rocks under the condition of high stress, the similar material simulation is verified by the numerical simulation with FLAC3D and the impacts of the coefficient of horizontal pressure and the cohesion on the size and the shape of the broken rock zone.Based on the results of the similar material simulation, theoretical analysis and numerical simulation, the control of the stability of the road-surrounding rocks is analyzed theoretically, then such control methods are put forward as the gradual supports, the timely stress restoration, the improvement of the stress state, consolidation and reparation, rock reinforcement and the reinforce for the key parts.For the existing problems on the supports of the deep roadway under the condition of high stress, based on the result of the theoretical analysis and the practice, the supporting project is designed with pertinence and the in situ engineering tests are carried out. It can be shown from the measured data that the supporting project used controls the big deformation and failure of the roadway rocks and improves the safety of the roadway, which verifies the feasibility of the project.更多还原