单轴压缩下多裂隙类岩石材料强度试验与数值分析

采用伺服控制单轴加载系统对预制多裂隙水泥砂浆试件进行加载试验，探索裂隙角度和分布密度对多裂隙类岩石材料断裂破坏强度的影响规律。对试验数据整理分析，应用FLAC3D建立应变软化模型，进行数值模拟。试验数据和数值分析结果表明，裂隙分布密度相同时，裂隙倾角对试件断裂破坏强度的影响比较显著，25°附近取得最小值；裂隙角度相同时，裂隙分布密度对试件断裂破坏强度的影响与裂隙倾角有关，角度较小时，影响比较显著，随着角度的增大，影响越来越弱。试验所得结论，对于预测地下工程中多裂隙情况下围岩强度变化规律提供了依据。

Numerical analysis and strength experiment of rock-like materials with multi-fissures under uniaxial compression

In the system of uniaxial loading with servo control, the experiment of uniaxial loading on the samples of prefabricated cement mortar with multiple fissures was made, aiming to explore the influencing rules of strength of fracture failure which belong to the rock-like material with different angles and densities of distribution of the fissures. Basing on the arrangement and analysis of the experimental data, a strain-softening model is established by using the software-FLAC3D; and then the numerical analysis of the strain-softening model carried out. The experimental data and the results of numerical calculation show that: When the density distributions of fissures are the same, the angle of the fissures plays an obvious part in the strength of fracture failure of the samples. And when the angle of the fissures is about 25°, it has the minimum value of strength. When the angles of the fissures are the same, the strength of fracture failure of the samples has a relationship with the density distribution of fissures. When the angle has a small value, the effects of density distribution of fissures are obvious. And with the increasing of the inclination angle of the fissures, the effects are increasingly weak. This conclusion provides a basis for predicting the changing rules of strength of the wall rock with multi-fissures in the underground projects.