含裂隙大理岩压缩破坏和能量特征颗粒流模拟

Particle flow simulation on compression failure and energy characteristics for marble containing pre-existing fissure

  • 摘要: 为了研究不同裂隙组合下岩石变形破坏机理和能量演化规律,对锦屏大理岩开展了X射线衍射(XRD)和单轴压缩试验,基于XRD结果和颗粒流程序生成三维等效晶质模型,结合完整岩样的单轴压缩试验结果进行细观参数标定,并建立不同裂隙组合的数值模型,对岩样变形破坏和能量演化进行模拟分析。结果表明:(1)试样强度随预制裂隙倾角的增加先增后减,随裂隙长度和轴向偏移量的增加而降低,随裂隙径向偏移量的增加先减后增;(2)裂隙倾角和空间位置对试样强度的影响程度均与裂隙长度有关,裂隙长度较大时,倾角会抑制轴向偏移的劣化作用甚至改变径向偏移的影响模式,裂隙倾角对试样强度的硬化效应在裂隙长度较大时愈加明显;(3)预制裂隙倾角、长度及其空间位置均可能会改变试样的破坏模式。

     

    Abstract: To study the mechanism of different fissure parameters on rock deformation and failure and law of energy evolution, the X-ray diffraction and uniaxial compression tests were conducted on Jinping marble. Firstly, three-dimensional GBM was generated based on the X-ray diffraction results and particle flow code. Then, the mesoscopic parameters was calibrated according to the results of uniaxial compression tests of intact marble sample, and the numerical model containing various fissure parameters was constructed. Finally, the process of the deformation and failure along with the energy evolution of numerical samples was simulated and analyzed. The results show that the strength of sample increases first and then decreases with the increasing fissure dip angle. The strength of sample is intensified with the increase of the axial offset and fissure length. With an increase in the radial offset of fissure, the strength of sample decreases first and then increases. In addition, the influence degree of dip and spatial position of fissure on the strength of sample is related to the fissure length. When the fracture length is large, the dip angle inhibits the deterioration of axial offset and even changes the influence mode of radial offset. The hardening effect of dip angle on the sample strength is more obvious as fissure length is larger. It is also found that the length, dip and spatial position of fissure significantly change the failure mode of sample.

     

/

返回文章
返回