多尺度节理岩体力学特性的颗粒流分析

以白云鄂博露天铁矿东矿岩质高边坡为工程背景，结合现场地质调查、室内岩石和节理力学试验等数据，采用等效岩体技术，构建能充分反映节理分布特征的实验室、现场原位试验和工程尺度等多尺度等效岩体模型。通过对各类等效岩体模型进行单轴压缩试验，研究岩体单轴抗压强度、弹性模量等力学特性的尺寸效应和各向异性。研究表明：节理的存在使岩体表现出尺寸效应和各向异性，且随着尺寸的增大，这种特性基本呈逐渐减弱的趋势；研究区域岩体的表征单元体积、单轴抗压强度和弹性模量分别为20 m×10 m×10 m、1.46 MPa和3.91 GPa；岩体单轴抗压强度、弹性模量与轴向尺寸的关系，近似符合渐进式指数函数关系，且该函数能直观地给出工程尺度岩体的力学特性。

Particle flow code analysis of multi-scale jointed rock mass based upon equivalent rock mass technique

Based on the in-situ observations of a high-steep rock slope in Baiyun Ebo eastern open-pit iron mine, and the data of mechanical properties of rocks and joints, an equivalent rock mass (ERM) model is developed to describe the joint distribution characteristics at multi scales from laboratory tests, in-situ tests to engineering applications. Uniaxial compression tests are conducted on rock mass ERM models to investigate the scale effect and anisotropic properties of uniaxial compressive strength and elastic modulus. The results show that the existence of joints results in the size effect and anisotropic behaviour of rock mass, and these properties tend to gradually weaken with the increase of rock block size. The representative elementary volume, uniaxial compressive strength and elastic modulus of rock mass in the selected research area are 20 m×10 m×10 m, 1.46 MPa and 3.91 GPa, respectively. The relation between uniaxial compressive strength, elastic modulus and the axial size of rock mass is approximately a gradual exponential function which can directly represent mechanical parameters of rock mass.