Cyclic loading–induced hazards are severe instability problems concerning surface and underground geotechnical projects. Therefore, it is crucial to understand the rock failure mechanism under cyclic loading. An innovative double-criteria damage-controlled testing method was proposed in this study to capture the complete stress–strain response of porous limestone, especially the post-peak behaviour, under systematic cyclic loading. The proposed test method was successful in applying the pre-peak cyclic loading and then in controlling the self-sustaining failure of rock during the post-peak cyclic loading. The results showed that the strength of the rock specimens slightly increased with an increase in the fatigue life in the pre-peak region due to cyclic loading–induced hardening. Additionally, a combination of class I and class II behaviours was observed in the post-peak region during the cyclic loading tests; the class II behaviour was more dominant by the increase in fatigue life in the pre-peak region. Damage evolution was assessed based on several parameters, such as the elastic modulus, energy dissipation ratio, damage variable and crack damage threshold stress, both in the pre-peak and post-peak regions. It was found that when the cyclic loading stress is not close to the peak strength, due to a coupled mechanism of dilatant microcracking and grain crushing and pore filling, quasi-elastic behaviour dominates the cyclic loading history, causing more elastic strain energy to accumulate in the specimens.

循环荷载引起的危害是涉及地面和地下岩土工程的严重不稳定问题。因此，了解循环荷载作用下的岩石破坏机理至关重要。在这项研究中，提出了一种创新的双标准损伤控制测试方法，以捕获多孔石灰石在系统循环载荷下的完整应力-应变响应，尤其是峰后的行为。所提出的测试方法成功地应用了峰值前的循环载荷，然后成功地控制了峰值后的循环载荷过程中岩石的自持破坏。结果表明，由于周期性载荷引起的硬化，岩石样品的强度随峰值前疲劳寿命的增加而略有增加。另外，在循环载荷测试期间，在峰后区域观察到I类和II类行为的组合；通过增加峰前区域的疲劳寿命，II类行为更为明显。根据峰前和峰后区域的几个参数（例如弹性模量，能量耗散率，损伤变量和裂纹损伤阈值应力）评估损伤演化。研究发现，当循环载荷应力不接近峰值强度时，由于膨胀微裂纹和晶粒破碎与孔隙填充的耦合机制，准弹性行为在循环载荷历史中占主导地位，从而导致更多的弹性应变能积累。标本。通过增加峰前区域的疲劳寿命，II类行为更为明显。基于峰前和峰后区域的几个参数，例如弹性模量，能量耗散率，损伤变量和裂纹损伤阈值应力，评估损伤的演变。研究发现，当循环载荷应力不接近峰值强度时，由于膨胀微裂纹和晶粒破碎与孔隙填充的耦合机制，准弹性行为在循环载荷历史中占主导地位，从而导致更多的弹性应变能积累。标本。通过增加峰前区域的疲劳寿命，II类行为更为明显。基于峰前和峰后区域的几个参数，例如弹性模量，能量耗散率，损伤变量和裂纹损伤阈值应力，评估损伤的演变。研究发现，当循环载荷应力不接近峰值强度时，由于膨胀微裂纹和晶粒破碎与孔隙填充的耦合机制，准弹性行为在循环载荷历史中占主导地位，从而导致更多的弹性应变能积累。标本。