In order to study the dynamic mechanics and failure behavior of jointed rock masses, impact tests were carried out on sandstone specimens with intersected jointed and unjointed intact sandstone specimens using a modified split Hopkinson pressure bar (SHPB) with confinement. The effects of intersected artificial joints on the dynamic properties and failure mechanism of sandstone samples were analyzed. The dynamic stress-strain curve of sandstone specimen was obtained from the test, as well as the fracture failure behavior of specimen under different loading rates and confining pressures. The results show that the dynamic compressive strengths of the unjointed intact rock specimens and the jointed rock specimens both increase with the increase of the loading rate and the confining pressure. With the increase of loading rate, the jointed rock specimens showed more obviously plastic deformation ability than the intact rock specimens, and the size of the broken pieces of the jointed rock samples became smaller. The dynamic failure modes of the jointed rock samples are irregular and mainly appear tensile and compressive shear failures. Next, the dynamic initiation and development process of cracks in the jointed rock specimens were analyzed by using the UDEC numerical simulation software. The process of initiation and development of meso-cracks is affected by intersected joints. Combined with the effective stress contour map, five typical crack types are defined to reveal the macroscopic fracture behavior of sandstone samples.

为研究节理岩体的动态力学和破坏行为，采用带约束的改进分裂霍普金森压力杆（SHPB）对具有交叉节理和无节理完整砂岩试件的砂岩试件进行了冲击试验。分析了交叉人工节理对砂岩试样动力特性和破坏机理的影响。试验得到了砂岩试件的动态应力-应变曲线，以及试件在不同加载速率和围压下的断裂破坏行为。结果表明，无节理完整岩石试件和节理岩石试件的动压强度均随加载速率和围压的增加而增加。随着加载速率的增加，节理岩样比完整岩样表现出更明显的塑性变形能力，节理岩样碎块尺寸变小。节理岩样的动态破坏模式是不规则的，主要表现为拉伸和压缩剪切破坏。接下来，利用UDEC数值模拟软件分析了节理岩石试件中裂纹的动态萌生和发展过程。细观裂纹的萌生和发展过程受相交节理的影响。结合有效应力等值线图，定义了五种典型裂纹类型，揭示了砂岩样品的宏观断裂行为。节理岩样碎块尺寸变小。节理岩样的动态破坏模式是不规则的，主要表现为拉伸和压缩剪切破坏。接下来，利用UDEC数值模拟软件分析了节理岩石试件中裂纹的动态萌生和发展过程。细观裂纹的萌生和发展过程受相交节理的影响。结合有效应力等值线图，定义了五种典型裂纹类型，揭示了砂岩样品的宏观断裂行为。节理岩样碎块尺寸变小。节理岩样的动态破坏模式是不规则的，主要表现为拉伸和压缩剪切破坏。接下来，利用UDEC数值模拟软件分析了节理岩石试件中裂纹的动态萌生和发展过程。细观裂纹的萌生和发展过程受相交节理的影响。结合有效应力等值线图，定义了五种典型裂纹类型，揭示了砂岩样品的宏观断裂行为。利用UDEC数值模拟软件分析了节理岩石试件裂纹的动态萌生和发展过程。细观裂纹的萌生和发展过程受相交节理的影响。结合有效应力等值线图，定义了五种典型裂纹类型，揭示了砂岩样品的宏观断裂行为。利用UDEC数值模拟软件分析了节理岩石试件裂纹的动态萌生和发展过程。细观裂纹的萌生和发展过程受相交节理的影响。结合有效应力等值线图，定义了五种典型裂纹类型，揭示了砂岩样品的宏观断裂行为。