论文部分内容阅读
针对岩爆形成机制研究的不足,结合岩爆实例和真三轴加、卸荷试验,分析了卸荷岩爆模式,建立了围岩卸荷岩爆发生劈裂破坏和剪切破坏的损伤变量表达式,即损伤演化方程。结果表明,岩爆破裂演化表现为劈裂和剪切的复合破坏形式,不同之处只是劈裂和剪切哪一个所占的成分更大而已;随着剪切成分的增大,爆坑由呈现平底到弧形甚至三角形或V形;随着应力的增加,岩爆倾向性围岩有一段时间的平静期(无损伤),具体平静期存在时间的长短与围岩卸荷前后的应力水平有关,损伤一旦开始则加速度明显,具有较强的临界敏感性;劈裂总是优先发生的,围岩卸荷后的应力水平越高含剪切成分越大,岩爆也越强烈。
Aiming at the shortcomings of the study on the mechanism of rockburst formation, combined with the rockburst example and the true triaxial adding and unloading test, the rockburst model of unloading is analyzed, and the damage variables of splitting failure and shear failure of rockburst are established The expression, damage evolution equation. The results show that the evolution of rock burst shows the composite failure mode of splitting and shearing, the only difference is that which component of splitting and shearing accounts for a larger part. With the increase of shearing component, Showing a flat to arcuate or even triangular or V-shaped; With the increase of stress, rock burst prone rock has a period of quiet period (no damage), the duration of specific calm period and the surrounding rock unloading stress level The damage is obvious once the start, with strong critical sensitivity; splitting always takes place preferentially. The higher the stress level of surrounding rock after unloading, the greater the shear component and the stronger rock burst.