【摘要】 为准确刻画节理岩体因空间非均匀分布导致的参数变异性，以西非某矿区典型铁英岩岩体为对象，通过整合节理产状数据，经空间聚类分析识别优势节理组，结合室内试验标定岩石与节理参数，基于3DEC平台构建节理岩体三维离散等效模型；通过联合分析单轴压缩模拟与力学参数变异系数，确定岩体代表性单元体积，开展不同剪切方向下的直剪数值试验。结果表明：节理空间构型显著影响岩体应力强度，法向应力从3、 5、10 MPa依次递增，X向剪应力增加56%、90%时，Y向剪应力增加48%、102%;在3、5、10 MPa法向应力下，Y向剪应力比X向剪应力增加32%、14%、20%;剪切过程中位移场呈现多向非均匀演化特征，剪应力方向为优势变形主导向，变形优先发生在与水平剪切应力夹角较小的中低倾角或近水平节理面。更多还原

【Abstract】 To accurately capture the parameter variability induced by the spatial heterogeneity of jointed rock masses, a typical itabirite rock mass in a West African mine was investigated. By combining joint orientation data, spatial cluster analysis was conducted for identifying dominant joint sets, and laboratory tests for parameter calibration were performed to build a 3DEC-based discrete equivalent model. Through a combined analysis of uniaxial compression simulations and the coefficient of variation of mechanical parameters, the REV of the rock mass was determined. Based on this, direct shear numerical experiments were conducted under different shear directions. The results indicate that the spatial configuration of joints significantly influences the rock mass′s shear strength. As the normal stress increases from 3 MPa to 5 MPa and then 10 MPa, the shear stress in the X-direction increases by 56% and 90%, while the shear stress in the Y-direction increases by 48% and 102%. Under normal stresses of 3, 5, and 10 MPa, the shear stress in the Y-direction is 32%, 14%, and 20% higher than that in the X-direction, respectively. During the shearing process, the displacement field exhibits multi-directional and non-uniform evolutionary characteristics, with the shear stress direction serving as the dominant orientation of deformation.更多还原