浸水软岩损伤破坏机理及巷道稳定性控制研究

发布时间：2018-04-16 04:16

本文选题：水-岩作用 + 损伤变量　；参考：《山东科技大学》2017年硕士论文

【摘要】：在高地应力和地下水耦合的复杂环境中,地下工程巷道围岩的物理力学性质将发生很大的改变,再加之自然成岩成分复杂,对于含大量亲水矿物成分的泥岩等软弱岩体,水对围岩造成的损伤有时比力学因素导致的损伤更为严重。本文从实验、理论和数值模拟方面对富水软岩的破坏机理及软岩巷道的长期稳定性控制问题开展研究:(1)基于连续介质损伤力学将水对岩石的损伤作用定义为对岩石力学参数的弱化效果。通过开展不同含水率下泥质粉砂岩单轴压缩试验引入与湿度相关的损伤变量Dω并加以函数表征,并拟合出了软岩在湿度场中的时效性损伤变量Dt的表达式;(2)基于切线法建立了以内聚力和内摩擦角为变量的等效M-C岩石非线性破坏准则,利用Flac3D内嵌的FISH语言编制程序,实现内聚力和内摩擦角的动态变化;通过相应单轴压缩试验的数值模拟证明了等效M-C准则能够有效的表征岩石非线性破坏特征和剪切、拉伸破坏状态;(3)结合时效性损伤变量Dt与现行的组合元件流变模型,以弱化流变参数的方式建立了能够具有衰减、稳态和加速蠕变三个阶段,瞬弹性、瞬塑性、粘弹性和粘塑性共存,并具有非线性破坏特征的修正Cvisc蠕变损伤本构模型;(4)将上述研究成果应用于小屯煤矿受富水环境影响的16中07运顺软岩巷道围岩稳定性的数值模拟研究中,从应力场、位移场、塑性区分布等方面进行了对比分析,结果表明了考虑水岩损伤作用的修正Cvisc蠕变损伤本构模型能较好的反映开水岩损伤作用对巷道稳定性的影响,同时对比分析了锚杆-锚索与锚网喷不同支护方案在长期控制方面的效果,为该类巷道的支护设计与优化处理提供参考。
[Abstract]:In the complex environment of high ground stress and groundwater coupling, the physical and mechanical properties of surrounding rock of underground engineering roadway will be changed greatly, and the natural diagenetic composition is complex, for weak rock mass, such as mudstone, which contains a large amount of hydrophilic mineral elements,The damage caused by water is sometimes more serious than that caused by mechanical factors.In this paper, from the experiment,In theory and numerical simulation, the failure mechanism of water-rich soft rock and the long-term stability control of soft rock roadway are studied. (1) based on continuum damage mechanics, the damage effect of water to rock is defined as the weakening effect of rock mechanics parameters.Through uniaxial compression test of shaly siltstone with different moisture content, the damage variable D 蠅 related to humidity is introduced and characterized by function.The expression of time-dependent damage variable Dt of soft rock in the humidity field is fitted. Based on the tangent method, the equivalent M-C rock nonlinear failure criterion with cohesion and friction angle as variable is established, and the program is compiled by FISH language embedded in Flac3D.The dynamic change of cohesive force and internal friction angle is realized, and the equivalent M-C criterion is proved to be effective in characterizing the nonlinear failure characteristics and shear of rock by numerical simulation of corresponding uniaxial compression test.In combination with the aging damage variable Dt and the current rheological model of the combined components, the three stages, namely, transient elasticity, transient plasticity, can be obtained by weakening the rheological parameters, which can have three stages: attenuation, steady state and accelerated creep.Viscoelasticity and viscoplasticity coexist,The modified Cvisc creep damage constitutive model with nonlinear failure characteristics is applied to the numerical simulation of surrounding rock stability of soft rock roadway in 16Zhong07, which is affected by water-rich environment in Xiaotun Coal Mine, from the stress field and displacement field.The results show that the modified Cvisc creep damage constitutive model, which considers the damage of water rock, can better reflect the influence of boiling rock damage on the stability of roadway.At the same time, the effects of different support schemes of bolt-anchor cable and bolt-net shotcreting in long-term control are compared and analyzed, which provides a reference for the support design and optimization treatment of this kind of roadway.
【学位授予单位】：山东科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD322.4

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