【作者】 万琳辉；

【导师】 曹平；

【作者基本信息】 中南大学 ， 土木工程， 2012， 博士

【摘要】 金川二矿区目前已开采至850米水平,距地表已接近或超过1000米。随着开采进入深部以来,开采中各种问题接踵而来,如巷道断面收敛、地下水的影响突出、上部充填体的稳定性等都严重影响矿区深部的安全生产,为此,金川集团公司设立了第一个以深部岩石为研究对象的科技攻关项目——《金川二矿区高强度采掘条件下的深部岩石力学研究》,研究金川二矿区深部岩石干燥和饱水两种状态下基础力学特性及其应用,本文结合此科技攻关项目,开展了金川二矿区深部岩体力学参数取值、岩石亚临界裂纹扩展、岩石粘弹塑性及水影响的研究。主要研究内容如下：(1)统计以往地应力资料,提出了深部地应力预测的拟合方程,根据已有850—1000米水平地质资料,采用有限元软件Midas-GTS模拟分析了850—1000米水平的地应力；根据深部岩石力学实验及深部地质调查结果,将现有岩体力学参数取值方法结合,给出了金川二矿区深部岩体力学参数建议值。(2)针对深部存在的较完整岩体巷道,围岩裂纹的扩展、贯通造成破坏的特点,选取大理岩与花岗岩作为研究对象,采用双扭试件常位移松弛法研究了两种岩石饱水与干燥状态下亚临界裂纹扩展规律,分析了水对亚临界裂纹扩展及门槛值的影响；在断裂力学基础理论与应力腐蚀基础上,进行了亚临界裂纹扩展理论工程应用的初步研究。(3)深部巷道断面收敛严重,具有很强的流变特性,且水的存在对其影响巨大,为此,选取了含辉橄榄岩及斜长角闪岩试样,采用分级增量循环加卸载的流变试验方案,研究了两种岩石在干燥和饱水状态下粘弹塑性,分析了水对两种岩石的粘弹塑性的影响。依据试验结果,选取了广义开尔文模型模拟试验结果,确定了其流变参数,分析了水对流变参数的影响。(4)对广义开尔文模型进行了改进,使其能适应岩石的破坏特点；基于流固耦合理论,推导了流固耦合作用下岩石有限元流变模型,为进一步程序开发研究提供了理论基础。(5)利用有限元软件Midas-GTS模拟分析了850米水平深部巷道的稳定性,依据分析结果,给出了巷道位置及断面选择的建议；利用有限差分法软件Flac3D,模拟分析了深部巷道断面收敛的时效性,依据模拟结果,给出了各个阶段支护重点部位；利用有限元软件Midas-GTS从应力和接触面等方面模拟分析了上部充填体稳定性。本文立足于金川二矿区实际工程,通过现场工程地质调查,运用试验、理论分析与数值分析等研究方法,对金川二矿区深部典型岩石和深部岩体工程稳定性问题进行了研究,其研究成果对金川二矿深部安全生产具有较重要的理论和实际意义。更多还原

【Abstract】 Jinchuan2th Mine has been mined to the level of850meters, its about1000meters to the ground surface. With mining, the deep mining problem was gradually revealed, for example, the roadway section convergence, groundwater, the stability of the upper part of backfill body,they seriously affect the deep mine safety production. Therefore, Jinchuan Group Company set up a science and technology key project for the study of the deep rock mechanics--<Study on the deep rock mechanics under high intensity in Jinchuan2th Mine>-to study the basic mechanical properties application of deep rock uder the dry or water-saturated environment. Basing on science and technology key project, the author has studied the parameter of rock mechanics, the propagation of rock subcritical crack, rock elasto-viscoplastic and the effect of water. The main contents are as follows:(1) According to statisticsing the previous ground stress data, a fitting equation has been given to predict the deep groud stress. According to the existing850-1000m level geological data, the ground stress of850-1000m level was simulated and analyzed; According to the the deep rock mechanics experiment and the deep geological findings, the parameter of deep rock mechanics was given by synthesis of existing rock mechanics parameter values.(2) The cracks of relatively complete surrounding rock in deep tunnels was propagated and coalesced to the damage of tunnels. The marble and granite samples were chosed to study the law of subcritical crack growth under dry and water-saturated environments and effect of water on subcritical crack growth was analyzed. On the basis of the basic theory of fracture mechanics and stress corrosion, a preliminary study of the engineering applications of subcritical crack propagation theory was conducted.(3) The deep roadway section seriously convergences with a strong rheological properties and convergence displacement was affected seriously by water. Therefor the lherzolite and amphibolites rock samples were selected to study its elasto-viscoplastic properties uder the dry or water-saturated environment by rheological test experiments of a circular incremental step load and unload method. The generalized Kelvin model was chosen to simulate rheological properties according to the experimental results, key parameters were obtained and effect of water was analyzed.(4) The Generalized Kelvin model has been improved to simulate the characteristics of rock destruction; Based on Fluid-solid Coupling Theory, the finite element rheological model of rock under the fluid-structure interaction effect was derivated and a theoretical basis was provided for further program development research.(5) The deep tunnel of850m level was simulated by the finite element software-Midas GTS and it’s stability was analyzed. According to the results of analysis, the recommendations were given to choose tunnel position and cross-section shape; the rheological property of deep tunnels cross-section convergence was simulated by Flac3D. According to the simulation results, the various stages of supporting key positions were given. From the stress and the contact surface, the upper backfill was simulated to analyze its stability by the finite element software Midas-GTS.Based on the actual project of Jinchuan2th Mine, the deep typical rock and the deep rock engineering stability has been studied by engineering geological survey, test, the theoretical analysis and numerical analysis. The result of research has important theoretical and practical significance to safety production of Jinchuan2th Mine.更多还原