Abstract:In order to elucidate the influence of cyclic loading and unloading paths on the energy evolution of hexagonal honeycomb, three different graded cyclic loading and unloading tests were designed, and the evolution characteristics and interrelationships of total external input energy, elastic deformation energy, dissipation energy and plastic deformation energy under different graded cyclic loading and unloading modes were revealed. The results show that the initial peak strength and platform stress of the honeycomb are related to the elastic energy release during the unloading process. Total external input energy, elastic deformation energy and plastic deformation energy of the honeycomb show a nonlinear increase with the increase of the number of unloading levels. However, the dissipation energy decreases with the number of unloading levels in the first three cycles, and the upper limit of the cycle load is larger in the last stage. The disturbance effect is stronger than the enhancement effect, and the dissipation energy shows an opposite trend. When the upper limit of the cyclic load is raised, the damage inside the honeycomb increases, and the closer to the initial peak strength of the honeycomb, the more serious the damage is. Besides, when the lower limit of the cyclic load is raised, less elastic energy is released, and the damage is intensified. The research achievements could be beneficial to revealing the damage and instability mechanism of honeycomb under different stress paths, and lays the theoretical foundation for honeycomb applications in mines and underground spaces.