层状节理岩体模型冲击实验

为研究层状节理岩体在冲击荷载作用下的力学特性，实验采用水泥砂浆预制层状节理岩体模型，设计4个落锤高度对不同节理组数的岩体进行冲击加载。通过对冲击过程中载荷及加速时程信号的分析处理，得出节理岩体动态承载力与节理组数呈负相关性，压缩位移与冲击高度呈正相关性；当冲击荷载较小时，节理岩体动态压缩位移主要来自节理法向闭合，节理周边开始产生细微裂缝；随着冲击荷载的逐渐增大，裂缝逐渐沿节理面扩展贯通导致岩体破坏。

Impact tests on model of layered and jointed rock mass

In order to study the mechanical properties of layered and jointed rock mass under impact loading, the model of layered and jointed rock mass was prefabricated by cement mortar in the tests, and four heights of drop hammer were designed to carry out impact loading on rock mass with different numbers of joint groups. Through the analysis and treatment of load and accelerating time history signals in impact process, it showed that the dynamic bearing capacity of jointed rock mass is negatively correlated with the number of joint groups, while there is a positive correlation between the compression displacement and the impact height. When the impact load is small, the dynamic compressive displacement of jointed rock mass is mainly derived from the joint normal closure, and minor cracks begin to appear around the joint. With the impact load gradually increases, the cracks gradually expand along the joint surface and lead to the failure of rock mass.