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.