CAJ | 학술논문

利用RMT–150B岩石力学多功能系统,对砂岩巴西劈裂疲劳破坏过程中的变形与强度特征进行试验研究.试验结果表明:常规劈裂试验峰值前的变形与单轴压缩的变形特征大致相同,可分为压密、弹性、屈服和破坏4个阶段;疲劳破坏完全受到常规劈裂全过程曲线的控制,破坏时的变形量与上限载荷(应力)在常规劈裂全过程曲线峰后对应的变形量相当;疲劳试验过程中的变形量(变形速率)与时间曲线类似蠕变特征曲线,可分为初期加速、等速和加速3个阶段;疲劳上限载荷(应力)比、抗拉疲劳强度与循环次数呈负相关,疲劳上限载荷(应力)比是影响岩石疲劳寿命主控因数,试样内部原微裂纹等缺陷分布特征对劈裂疲劳寿命影响显著;疲劳上限载荷(应力)比增加导致疲劳寿命降低,而破坏时拉伸变形基本保持不变.
이용RMT–150B암석역학다공능계통,대사암파서벽렬피로파배과정중적변형여강도특정진행시험연구.시험결과표명:상규벽렬시험봉치전적변형여단축압축적변형특정대치상동,가분위압밀、탄성、굴복화파배4개계단;피로파배완전수도상규벽렬전과정곡선적공제,파배시적변형량여상한재하(응력)재상규벽렬전과정곡선봉후대응적변형량상당;피로시험과정중적변형량(변형속솔)여시간곡선유사연변특정곡선,가분위초기가속、등속화가속3개계단;피로상한재하(응력)비、항랍피로강도여순배차수정부상관,피로상한재하(응력)비시영향암석피로수명주공인수,시양내부원미렬문등결함분포특정대벽렬피로수명영향현저;피로상한재하(응력)비증가도치피로수명강저,이파배시랍신변형기본보지불변.
The deformation rules and strength characteristics of sandstone samples in the process of Brazilian split fatigue load were studied by the RMT–150B multi-function servo system. The results showed that there were almost same deformation characteristics in both the conventional split test and uniaxial compression test before the peak load,which could also be divided into 4 stages including compression,elasticity,yielding and failure stage. The destroy mode of Brazilian split fatigue was controlled completely by the fracture process curve of the conventional Brazilian split;and the deformation value and upper limit load(stress) were equivalent to the corresponding deformation in the post-peak process curve of the conventional Brazilian split test. The deformation(rate) curve versus time in the process of splitting fatigue test was similar to the creep characteristics curve,which could be divided into 3 stages including initial acceleration,constant velocity and acceleration stage;and the fatigue limit load(stress) ratio and the tensile fatigue strength were negatively correlated with the cycle number. The fatigue upper limit load(stress) was the main control factor impacting the rock fatigue life;and the internal original microcrack distribution of sandstone sample had great influences on the split fatigue life. The increase of the upper fatigue limit load(stress) leaded to reductions in fatigue life;while the tensile deformation basically unchanged.