关键词: 能量演化, 渐进破坏, 特征应力, 三轴压缩, 岩爆

Abstract: Exploring the progressive failure of rock samples and the law governing energy evolution helps clarifying the inherent mechanism of rock damage. Triaxial compression tests were conducted on dolomite rock samples to investigate the influence of various factors, such as, confining pressure characteristics, the stress and strain energy. The correlations among the total absorbed energy, the elastic strain energy and the dissipated energy at distinct stages of rupture are analyzed, and the potential mechanisms governing their variations are evaluated. The major findings are as follows: (1) With an increase in the confining pressure, all characteristic stresses exhibit a linear growth. The peak stress corresponds to the compressive strength of dolomite rock samples, which adhere to the Mohr-Coulomb criterion. (2) As the confining pressure rises, the strain energy increases linearly. The crack initiation stress illustrates the accumulation of the elastic strain energy; while the energy dissipation at the point of crack damage stress initiates accelerated growth and dominates at the peak stress, rendering it susceptible to an unstable damage. (3) rock burst potential indices increase significantly as the confining pressure decreases. Following the excavation and the unloading, it is recommended to install stress-relief holes or concrete supports for the effective control of the rock burst.

Key words: Energy Evolution, Progressive Failure of Rock Samples, Characteristic Stress, Triaxial Compression, Rock Burst