CAJ | 학술논문

地下储气库围岩长期处于复杂疲劳应力状态下，盐岩三轴循环荷载下的变形规律对储气库稳定性分析有参考价值。对8个盐岩试块进行了不同围压、不同应力水平和不同频率条件下的循环荷载试验。对每一试块施加恒定围压和轴向低频循环荷载。对试验参数进行了无量纲处理，分析了应力比强度（广义剪应力强度与球应力的比值）、应力比振幅、上限应力水平、荷载频率、循环次数（N）等对体积应变（εv）的影响。利用函数εv=λlgN+εv0，对每一试块的体积应变–循环次数曲线进行了拟合分析，获得了参数λ和εv0随应力比振幅、上限应力水平和频率变化的数学表达式。标准化回归系数分析表明，上限应力水平是影响盐岩体积变形的主要因素，其次是应力比振幅。在高上限应力水平三轴状态下，盐岩主要表现出体积扩大现象。
지하저기고위암장기처우복잡피로응력상태하，염암삼축순배하재하적변형규률대저기고은정성분석유삼고개치。대8개염암시괴진행료불동위압、불동응력수평화불동빈솔조건하적순배하재시험。대매일시괴시가항정위압화축향저빈순배하재。대시험삼수진행료무량강처리，분석료응력비강도（엄의전응력강도여구응력적비치）、응력비진폭、상한응력수평、하재빈솔、순배차수（N）등대체적응변（εv）적영향。이용함수εv=λlgN+εv0，대매일시괴적체적응변–순배차수곡선진행료의합분석，획득료삼수λ화εv0수응력비진폭、상한응력수평화빈솔변화적수학표체식。표준화회귀계수분석표명，상한응력수평시영향염암체적변형적주요인소，기차시응력비진폭。재고상한응력수평삼축상태하，염암주요표현출체적확대현상。
The surrounding rock salt of underground gas storage cavern is subjected to long-term triaxial fatigue stress. The deformation property of rock salt under triaxial cyclic loading is of great importance to the stability of the rock salt cavity. A series of laboratory tests are performed to explore the deformation behavior of eight rock salt specimens under various confining pressures, stress levels and loading frequencies. The axial low-frequency cyclic stress is applied on each salt specimen while the confining pressure is kept steady. The test parameters are processed by the dimensionless method. The effects of the strength of stress ratio (ratio of generalized shear strength to spherical stress), amplitude of stress ratio, level of the maximum stress, loading frequency and loading cycles (N) on the volumetric strain (εv) of rock salt are analyzed. The nonlinear curve fitting is carried out using the functionεv =λlgN+εv0 for a curve of each specimen on the volumetric strain with the cycles. Further, the expressions for the parametersλ andεv0 with the amplitude of stress ratio, the maximum stress and loading frequency are obtained, respectively. The analysis of standardization regression coefficient indicates that the maximum stress is the key factor that influences the volumetric deformation of rock salt, and the stress amplitude ratio comes the second. It is noted that the rock salt exhibits dilatancy under high maximum stress.