Cyclic triaxial tests on the Ningbo saturated remolded clayey silt were carried out to study the effects of drainage condition, confining pressure, dynamic stress and temperature on the dynamic characteristics of soil. An empirical formula considering the effect of confining pressure， for the relationship between the dynamic elastic modulus and elastic strain was built. In addition, two empirical formulas for calculating the dynamic elastic modulus and the elastic strain under different confining pressure and dynamic stress were also established. The results show that with the increase of the number of vibration times, the dynamic elastic modulus and elastic strain at first change rapidly up to their extreme points and then after the extreme points, the dynamic elastic modulus and elastic strain gradually recover and approach to their stable state. The higher the temperature, the greater the value of dynamic elastic modulus and the smaller the elastic strain ( thermal hardening). The empirical formulas can be used to calculate the dynamic elastic modulus and the elastic strain of clayey silt after enduring longterm vibration load.
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