厚泥岩顶板巷道围岩变形破坏机理及其支护技术研究

发布时间：2018-03-10 01:15

本文选题：围岩弱化　切入点：渗流作用　出处：《安徽理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：目前,随着煤矿开采深度越来越深,地下水正逐渐成为影响巷道围岩稳定性的重要原因之一,位于巷道围岩周围的应力场和位移场时刻都受到含水层的影响。本文通过现场调研,分析了引起巷道围岩变形破坏的影响因素,再将理论分析和数值模拟相结合,对含水层作用下巷道围岩的变形破坏机理进行了分析。通过假设岩体是质地均匀、各向同性的等效连续渗透介质,原岩应力为各向等压,渗流方向主要以径向渗流为主,液体是单相、不可压缩且为牛顿流体,渗透过程符合达西定律。应用有效应力代替总应力的修正后的摩尔-库伦屈服准则,结合渗流作用及围岩应变软化模型与破裂膨胀模型,求出圆形巷道围岩变形破坏区域范围,并推导出了巷道围岩变形破坏后各区域的半径和位移。通过算例分析,得出了支护阻力、原始渗透水压力、应变软化以及破裂膨胀与有水作用下的巷道塑性区范围之间的关系。研究表明,结合渗流作用、应变软化以及破裂膨胀特性情况下将会使结果更贴近于实际,能更加真实地显现出围岩变形破坏状态。应用flac3D数值模拟软件,对照有渗流作用和无渗流作用下巷道的应力场、位移场以及塑性区的变化规律,并且在有渗流作用下,讨论了原支护方案支护效果的不足之处,同时对支护参数进行优化并提出了新的支护方案,最后利用数值模拟以及现场试验对新的支护方案进行了验证,从而得知新的支护方案比原方案能更好地控制围岩变形,这也为其他类似条件下工程的优化支护设计及安全性评价提供了参考依据。
[Abstract]:At present, with the depth of coal mining is more and more deep groundwater is becoming one of the important factors affecting the stability of surrounding rock in roadway surrounding rock, the surrounding stress field and displacement field are always affected by aquifer. Through field investigation, analysis of the factors causing the deformation and failure of the roadway surrounding rock, the theoretical analysis and numerical combining simulation, the deformation and failure mechanism of roadway surrounding rock aquifer under the effect are analyzed. By assuming that the rock is homogeneous, isotropic continuous infiltration medium, the original rock stress for isotropic seepage pressure, mainly in the direction of radial flow, liquid phase, incompressible and Newton fluid permeability the process accords with Darcy's law. Moore modified effective stress instead of total stress in Kulun after the yield criterion, combined with the seepage and rock strain softening model and rupture expansion mode Calculate the damage area, deformation of circular tunnel, and deduces the surrounding rock deformation radius and displacement after each region. Through the example analysis, it was concluded that the support resistance, the original osmotic pressure, strain softening and expansion and rupture of roadway water under the action of the relationship between plastic zone. Research shows that the combination of seepage, strain softening and swelling characteristics of rupture case will make the results more close to the practice, can more accurately reveal the deformation and failure of surrounding rock. Using numerical simulation software flac3D, the control of stress seepage and seepage tunnel field, displacement field and plastic zone changes and, in under the action of seepage, discusses the original supporting scheme supporting effect of deficiencies, and to optimize the support parameters and proposes a new supporting scheme, finally using numerical simulation and field The new support scheme is verified by experiments, which shows that the new support scheme can better control the deformation of surrounding rock than the original scheme, which also provides a reference for other similar conditions of the optimal support design and safety evaluation of the project.

【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD322;TD353

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