为了探究岩石单轴压缩试验过程中的能量演化规律，利用RMT-150b岩石力学测试系统采用相同的加载速率对白砂岩分别进行了单轴压缩试验、单轴分级加卸载试验。基于裂纹产生及扩展模型研究，假设疲劳损伤和裂纹间的界面摩擦对弹性能无影响，则可以认为单轴压缩中与单轴分级加卸载各卸载点荷载相等处，弹性能均相等。基于上述假设对单轴压缩过程中弹性能、耗散能、弹性能占总能量比例、耗散能占总能量比例、弹性能与耗散能比值等进行分析。通过利用红砂岩单轴循环加卸载中弹性能的演化规律验证了这一假设的正确性。研究结果表明:① 通过对单轴压缩试验过程中能量演化规律分析发现塑性耗散能、弹性能、滞回效应耗散能存在于岩石单轴压缩的各个阶段。② 部分滞回效应能可以储存在岩石内部并且随着荷载增大呈线性增长。③弹性能与塑性能的增长速率都随着荷载增大而增大，通过对弹性能与耗散能比值分析，得出了不同荷载范围内岩石的弹性能与耗散能增长速率的比较，并且在岩石强度的80%左右处弹性能与耗散能比值达到最大，与弹性能量指数相等，说明该分析方法对岩石能量演化趋势的分析具有一定的合理性。④ 通过红砂岩单轴循环加卸载试验分析发现，疲劳损伤和裂纹间的界面摩擦会产生塑性变形导致岩石加卸载曲线逐渐右移，且对弹性能无影响。⑤根据单轴分级加卸载各卸载点弹性能分析单轴压缩试验过程中能量演化规律，并使用单轴循环加卸载试验的弹性能演化规律进行验证，说明了分析方法的正确性。

In order to investigate the sandstone energy evolution behavior under the unconfined compressive condition,with the same loading rate,the uniaxial graded loading and unloading tests and unconfined compressive tests were carried out by using the RMT-150b rock mechanics tests system. Based on the research of crack generation and growth model,assuming that fatigue damage and interface friction between cracks have no effect on the elastic energy,it can be considered that the elastic energy is equal when the load of uniaxial compression is equal to the load of uniaxial graded loading and unloading. Based on the above assumptions,the elastic property,dissipated energy,elastic energy proportion to the total energy,dissipated energy proportion to the total energy,the ratio of elastic energy to dissipated energy and so on in the process of uniaxial compression were analyzed. The performance evolution of red sandstone under uniaxial cyclic loading and unloading was used to verify the correctness of this hypothesis. The research results show that ① Through the analysis of the evolution law of energy during the uniaxial compression test,it is found that the plastic dissipated energy,elastic energy and hysteretic effect dissipated energy exist at each stage of the uniaxial compression test of rock;② Some partial hysteretic effects can be stored in the rock and increase linearly with the increase of load;③ The growth rates of elastic energy and plastic energy increase as the load increases. By means of ratio analysis of elastic energy and dissipation energy,within different load ranges,the growth rates of rock elastic energy and dissipation energy can be compared in real time. When the rock strength reaches 80% ,the ratio of rock elastic energy and dissipation energy can reach its maximum,and be equal to the elastic energy index,which indicates that the analysis method of rock energy real-time evolution trend analysis has certain rationality;④ Through the uniaxial cyclic loading and unloading test analysis of red sandstone,it is found that the interface friction between fatigue damage and crack will produce plastic deformation,which causes the rock loading and unloading curve to gradually shift to the right,and has no impact on the elastic energy;and ⑤ According to the energy evolution law in the uniaxial compression test process during the analysis of elastic energy at each unloading point of uniaxial graded loading and unloading tests,and the elastic energy evolution law of uniaxial cyclic loading and unloading test is used to verify the correctness of the analysis method.