Abstract：Through the dynamic triaxial tests of structural soft soils，the dynamic strain analysis is conducted on the silt soils under traffic load，and the influence of vibration type，vibration frequency，stress ratio，consolidation status of soils are taken into account. The variation rules of the critical dynamic stress ratio of the silt soils and dynamic stress-strain with vibration frequency，confining stress and consolidation status are obtained. Some conclusions can be drawn from the research：(1) there is a critical dynamic stress ratio and a threshold of vibration frequency for structural silt soils under traffic load；(2) there is a turning-point for the dynamic elastic modulus and dynamic shear strain of silt soil under half-sine wave condition.
