Scholarlink

<p>With the increasing exploitation of mineral resources at greater depths, the complex geomechanical environment characterized by high in-situ stress and frequent engineering disturbances poses a serious threat to mining safety. This study focuses on granite. Multi-stage cyclic loading pre-damage tests under different confining pressures (10, 30, 50, and 80&#xa0;MPa) were designed and conducted, followed by uniaxial compression failure tests on the predamaged specimens, with the entire loading process monitored in real time using acoustic emission technology. The results indicate that: (1) Under low confining pressures (≤ 30&#xa0;MPa), hysteresis loops evolve actively and peak strain fluctuates significantly, whereas under high confining pressures (≥ 50&#xa0;MPa), hysteresis loops show stable convergence and peak strain evolves progressively; (2) Dissipated energy accumulates in a stepwise linear manner, driving damage to follow a U-shaped evolution within each loading stage while increasing steadily between stages; (3) For predamaged specimens, the acoustic emission count amplitude threshold shifts rightward (45 dB) and high-amplitude events (&gt; 86 dB) extend in duration. The AE dominant frequencies consistently exhibit a stable dual-band structure and pre-damage does not alter the ‘tension-shear partitioning’ cracking mechanism of the specimens. This research elucidates the macro-meso failure mechanisms of granite under deep cyclic disturbance, providing a quantitative theoretical and experimental basis for stability monitoring and disaster early warning in deep engineering rock masses.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Study on the Failure and Acoustic Emission Characteristics of Granite Under Deep Cyclic Disturbance

  • 期刊论文

  • 发表日期：

    2026年4月29日

查看全文
  • Dongjie Yang,
  • Zhonggen Cao,
  • Guoxun Jing,
  • Jianhua Hu,
  • Zhenwei Duan

摘要

With the increasing exploitation of mineral resources at greater depths, the complex geomechanical environment characterized by high in-situ stress and frequent engineering disturbances poses a serious threat to mining safety. This study focuses on granite. Multi-stage cyclic loading pre-damage tests under different confining pressures (10, 30, 50, and 80 MPa) were designed and conducted, followed by uniaxial compression failure tests on the predamaged specimens, with the entire loading process monitored in real time using acoustic emission technology. The results indicate that: (1) Under low confining pressures (≤ 30 MPa), hysteresis loops evolve actively and peak strain fluctuates significantly, whereas under high confining pressures (≥ 50 MPa), hysteresis loops show stable convergence and peak strain evolves progressively; (2) Dissipated energy accumulates in a stepwise linear manner, driving damage to follow a U-shaped evolution within each loading stage while increasing steadily between stages; (3) For predamaged specimens, the acoustic emission count amplitude threshold shifts rightward (45 dB) and high-amplitude events (> 86 dB) extend in duration. The AE dominant frequencies consistently exhibit a stable dual-band structure and pre-damage does not alter the ‘tension-shear partitioning’ cracking mechanism of the specimens. This research elucidates the macro-meso failure mechanisms of granite under deep cyclic disturbance, providing a quantitative theoretical and experimental basis for stability monitoring and disaster early warning in deep engineering rock masses.