In order to reveal the influence of prophase stress levels on the fatigue damage characteristics of granite, uniaxial fatigue tests of granite with different prophase stress levels were carried out on the basis of the MTS 815.04 rock mechanics test system. The results show that, under the same number of cycles, the failure degree increases with the increase of the prophase stress level. Under the low upper limit of cyclic stress, the tangent modulus and dissipated energy increase significantly with the increase of prophase stress level at the early stage of the cycle loading, while the increasing trend is not obvious with the increase of prophase stress level at the late stage. Under the high upper limit of cyclic stress, the tangent modulus and dissipated energy are less affected by the prophase stress level. The development trend of elastic release energy is not obvious with the increase of prophase stress level, which is less affected by the number of cycles. From the damage parameters defined by dissipative energy, under the low upper limit of cyclic stress, the initial damage is less affected by the prophase stress level. With the increase of the number of cycles, the influence of the prophase stress level on the development trend of the damage variable increases gradually. And the development trend of damage variables shows “C-shaped” damage.

中文翻译：

---

不同前期应力水平对花岗岩疲劳损伤特性影响的研究

为揭示前期应力水平对花岗岩疲劳损伤特性的影响，基于MTS 815.04岩石力学试验系统，对不同前期应力水平的花岗岩进行了单轴疲劳试验。结果表明，在相同的循环次数下，破坏程度随着前期应力水平的增加而增加。在循环应力低上限下，循环加载初期切线模量和耗散能随着前期应力水平的增加而显着增加，而随着前期应力水平的增加，增加趋势不明显。阶段。在较高的循环应力上限下，切线模量和耗散能受前期应力水平的影响较小。弹性释放能随前期应力水平的增加而发展趋势不明显，受循环次数的影响较小。从耗散能定义的损伤参数来看，在循环应力下限下，初始损伤受前期应力水平的影响较小。随着循环次数的增加，前期应力水平对损伤变量发展趋势的影响逐渐增大。且损伤变量的发展趋势呈“C型”损伤。随着循环次数的增加，前期应力水平对损伤变量发展趋势的影响逐渐增大。且损伤变量的发展趋势为“C型”损伤。随着循环次数的增加，前期应力水平对损伤变量发展趋势的影响逐渐增大。且损伤变量的发展趋势呈“C型”损伤。