【作者】 牛少卿；

【导师】 杨双锁；

【作者基本信息】 太原理工大学 ， 采矿工程， 2011， 硕士

【摘要】 煤炭是我国的主要能源,近年来,随着我国煤矿开采的深度不断增加,工作面顺槽围岩的支护问题显的越来越重要。工作面顺槽经历掘进、上区段工作面回采和下区段工作面回采,整个过程中围岩表现出特殊的非线性力学行为使得传统的岩体(石)力学理论与分析方法面临着新的挑战。长壁开采条件下三顺槽中间顺槽在下区段工作面开采后依然保留,相对于传统单、双顺槽回采存在围岩劣化更为严重,结构更不稳定等不利因素,巷道中二次应力场相互叠加、围岩力学性质劣化、围岩—支护结构性失稳是导致顺槽失稳、破坏的重要原因。因此,正确认识工作面回采过程中巷道围岩的物理性质、力学性质,建立合理的岩体本构关系和顺槽的力学结构模型,揭示二次应力场的叠加情况和围岩—支护相互作用机理显得非常重要。为了满足煤矿建设和安全生产的要求,推进科学技术在生产实践中的应用,本文围绕长壁开采工作面三顺槽稳定性控制问题,以亚美大宁煤矿104和105工作面之间的三顺槽为工程背景,在继承现有围岩控制、支护理论技术研究成果的基础上,系统地从围岩变形与破坏形式、岩体本构模型、三顺槽力学结构、围岩与支护作用机理、顺槽矿压特征五个方面形成了一个较完整的长壁开采三顺槽围岩稳定性分析控制方法。概括之,本文主要研究工作与获得的有益认识如下：1.不同的地质条件、不同的工程背景下,围岩的变形与破坏形式和机理不尽相同。本文详细的论述了顺槽在工作面回采中围岩破坏失稳形式,并对其破坏形式和机理进行了独有的分析,提出了新见解。2.针对目前弹塑性本构模型在模拟开挖空间围岩松动、破碎、破裂圈内围岩方面不理想的问题,从岩体宏观方向出发,提出了煤岩体进入塑性区后强度曲线在最大—最小主应力平面绕固定点旋转,与之对应的强度屈服面在主应力空间收缩膨胀的观点,并指出了根据三轴压缩试验曲线中任意两条确定强度参数变化的简便方法。利用岩体峰后强度参数随塑性应变变化予以描述岩体峰后本构关系,从而实现对松动、破碎、破裂区围岩的合理描述。并应用于数值计算。3.利用关键层理论、砌体梁理论和经典力学理论建立长壁开采三顺槽不同阶段时围岩的力学结构模型,并推导出了不同阶段支护力、煤柱宽度、煤岩力学特性之间的关系式,进而提出了维持顺槽结构稳定的条件4.利用建立的围岩力学结构模型分析煤柱的受力和物理力学状态,从而得出顺槽帮部和煤柱上的支撑压力分布特征。5.利用回采巷道围岩波动性支护理论分析顺槽支护结构变形和支护力之间的关系,提出了顺槽在工作面回采过程中的支护原则。6.将上述成果应用于亚美大宁煤矿104与105工作面间的三顺槽501、502、503的稳定性控制,利用理论公式对不同开采阶段中现场中顺槽的支护力进行计算,利用数值计算手段分析顺槽巷道的应力场分布和围岩破坏深度,最后通过现场观测验证其合理性。更多还原

【Abstract】 Coal is China’s major energy, recently, as the depth of coal mining increases, the support of surrounding rock is more and more important. Working surface roadway experience the excavation, mining on the section and under section, in the whole process, surrounding rock shows special nonlinear mechanical behavior, so the nonlinear traditional rock mass (rock) mechanics theory and analysis method will confront with new challenges. In addition, the deterioration of surrounding rock mechanics properties, the superposition secondary stress field, the superimposition and the instability of surrounding rock bolting structural are the important reasons leading to the instability and destruction of roadway. Therefore, understanding the physical properties and mechanical properties of the surrounding rock correctly, establishing the rational mechanical structure model of roadway and constitutive relation of rock mass, and finding the superposition situation of secondary stress and the interaction mechanism of rock and support are very important.In order to meet the requirements of mine construction and safety production and promote science and technology application in practice, under the engineering background of the three roadway of working surface of 104 and 105# mining face in Yamei Daning coal mining, on the basis of research achievements of the existing surrounding rock control theory and support technology, this thesis focuses on three roadway of longwall mining face, formed a complete control method of the three roadway rock stability analysis in longwall mining, from five aspects such as:the surrounding rock mass deformation and failure modes, constitutive model, the mechanical structure of three roadway, the mechanism of rock and support, and the rock pressure characteristics of the roadway systematically, In sum, the main work and conclusion including:1. The deformation, failure form and mechanism of the surrounding rock are different under the different geological conditions and engineering background. This thesis discussed on the instability forms of rock destruction during roadway in the mining face driving, and makes special analysis on the damage form and mechanism.2. Aimed at the problem of surrounding rock loose, crushing, rock burst when elastic-plastic constitutive model simulating the excavation space, the thesis proposed the opinion that the yield surface contracts when the coal rock enter the plastic zone under low confining pressure and the yield surface expands when the coal rock enter the plastic zone under high confining pressure, and applying the theory that rock strength parameter after peak changed with strain to realize reasonable description of the loose, crushing, ruptured surrounding rock, and applied in numerical calculation.3. This thesis established three roadway surrounding rock mechanics structure model of different stages in longwall mining applying key strata theory, voussoir beam theory and classical mechanics theory, deduced the relations of supporting force, coal pillar width, and coal rock mechanics properties during the different stages, and put forward the conditions to maintain roadway structure stability.4. Applying the established rock mechanics structure model to analyses the pillar stress and physical-mechanical condition, and the stress distribution of the roadway sides and coal pillar is got.5. This thesis analyzed the relationship of roadway support structure deformation and supporting force by the theory of fluctuant equilibrium of in teraction between surrounding rock and support of roadway, and gives supporting principle in the process of extraction.6. The results are applied in three roadway 501,502 and 503# of the Yamei Daning coal mine 104 and 105 mine face, supporting force at different mining stage is calculated by theory formula, the stress distribution of roadway and the depth of the surrounding rock destruction are analyzed by numerical calculation method, and the feasibility can be verified through the field observation.There are 187 figures,10 tables and 91 references更多还原