CAJ | 학술논문

通过低温动三轴试验，采用分级加载方式逐级施加动荷载，对不同加载频率、围压和负温条件下青藏冻结黏土和兰州黄土的动应变幅值变化特征进行了试验研究。结果表明，同一级荷载作用下，动应变幅值随振次的增加基本不变，可以采用平均值来反映各级加载下的动应变幅值；不同加载频率、围压和温度条件下，动应变幅值随动应力幅值的变化规律相同，即随着动应力幅值的增加，动应变幅值逐渐增大；动应变幅值随加载频率的增加而减小，但减小的速率逐渐降低，动应变幅值最终趋于一稳定值，对于青藏黏土和兰州黄土，该稳定值均随加载级数的增加而增加；随着围压的增加，青藏黏土的动应变幅值变化不大，而兰州黄土的动应变幅值呈逐渐减小的趋势；动应变幅值随温度的降低而减小。动应力幅值对动应变幅值的影响最大，动荷载振动频率的影响次之，温度的影响第三，围压的影响最小。
통과저온동삼축시험，채용분급가재방식축급시가동하재，대불동가재빈솔、위압화부온조건하청장동결점토화란주황토적동응변폭치변화특정진행료시험연구。결과표명，동일급하재작용하，동응변폭치수진차적증가기본불변，가이채용평균치래반영각급가재하적동응변폭치；불동가재빈솔、위압화온도조건하，동응변폭치수동응력폭치적변화규률상동，즉수착동응력폭치적증가，동응변폭치축점증대；동응변폭치수가재빈솔적증가이감소，단감소적속솔축점강저，동응변폭치최종추우일은정치，대우청장점토화란주황토，해은정치균수가재급수적증가이증가；수착위압적증가，청장점토적동응변폭치변화불대，이란주황토적동응변폭치정축점감소적추세；동응변폭치수온도적강저이감소。동응력폭치대동응변폭치적영향최대，동하재진동빈솔적영향차지，온도적영향제삼，위압적영향최소。
Dynamic triaxial test is performed to study dynamic strain amplitude of Qinghai-Tibet frozen clay and Lanzhou loess under staged dynamic loading with different loading frequencies, confining pressures and negative temperature conditions. The results show that the dynamic strain amplitude is basically unchanged with increasing vibration cycles under the same load level;and average values are used to characterize dynamic strain amplitude. The law of that dynamic strain amplitude changes with dynamic stress amplitude are the same;namely dynamic strain amplitude increases with increasing of dynamic stress amplitude with different loading frequencies, confining pressure and negative temperature conditions. Dynamic strain amplitude decreases with increasing of loading frequencies, but the decreased rate is becoming more and more small that it tends to be a stable value, which increases with the increasing of loading series. With increasing of confining pressure, dynamic strain amplitude for Qinghai-Tibet clay is basically unchanged and for Lanzhou loess decreases gradually. Dynamic strain amplitude decreases with decreasing temperature. The most important effect on dynamic strain amplitude is dynamic stress amplitude, vibration frequencies of dynamic load secondly, temperature thirdly, and confining pressure with minimal impact.