CAJ | 학술논문

利用MTS Landmark伺服加载试验对砂岩开展循环点荷载试验并对其力学特性进行研究。试验包含恒幅循环加载和荷载逐渐增加的多级循环加载两种方式，其加载频率和下限荷载比的变化范围分别为0.1~5 Hz和0~0.60。分析加载频率和下限荷载比对红砂岩疲劳寿命和滞回特性的影响。结果显示：红砂岩疲劳寿命随加载频率和下限荷载比的增加呈现先减后增的变化规律；在相同循环次数下，滞回环间距随加载频率的增大和下限荷载比的减小而不断增加。同时，红砂岩在循环点荷载作用下仍存在“锻炼”和“记忆”效应。
이용MTS Landmark사복가재시험대사암개전순배점하재시험병대기역학특성진행연구。시험포함항폭순배가재화하재축점증가적다급순배가재량충방식，기가재빈솔화하한하재비적변화범위분별위0.1~5 Hz화0~0.60。분석가재빈솔화하한하재비대홍사암피로수명화체회특성적영향。결과현시：홍사암피로수명수가재빈솔화하한하재비적증가정현선감후증적변화규률；재상동순배차수하，체회배간거수가재빈솔적증대화하한하재비적감소이불단증가。동시，홍사암재순배점하재작용하잉존재“단련”화“기억”효응。
The mechanical properties of red sandstone subjected to cyclic point loading were investigated. Tests were conducted using MTS servohydraulic landmark test system, under cyclic loadings with constant amplitudes and increasing multi-level amplitudes. The frequencies range from 0.1 to 5 Hz and lower limit load ratios range from 0 to 0.60. Laboratory investigations were performed to find the effect of the frequency and the lower limit load ratio on the fatigue life and hysteresis properties of sandstone. The results show that the fatigue life of sandstone decreases first and then increases with the increase of frequency and lower limit load ratio. Under the same cycle number, the spacing between hysteresis loops increases with rising frequency and decreasing lower limit load ratio. The existence of “training” and “memory” effects in red sandstone under cyclic point loading was proved.