Experimental Study on Dynamic Characteristic of Soft Soil under Cyclic Loading

In order to research the dynamic characteristics change of soft soil due to cyclic loading and the induced particular inadequate bearing capacity of roadbed,taking the soft soil in Yingkou area as the research object,a series of dynamic triaxial test are performed to research the influence of dynamic stress amplitude, consolidation confining pressure,consolidation ratio,vibration frequency and vibration times on dynamic characteristics of soft soil are researched. The test results show that( 1) Yingkou soft soil has a significant structural property,there is a strain turning point in the e d- N curves and the dynamic backbone curves,the deformation of soil increases rapidly when the strain is larger than this turning point strain;( 2) the dynamic strength increases as consolidation confining pressure increasing,but the influences of consolidation ratio and vibration frequency on soft soil dynamic strength are not always increasing or decreasing;( 3) the dynamic modulus increases as consolidation confining pressure,consolidation ratio and vibration frequency increasing, while the dynamic damping ratio decreases as consolidation confining pressure and consolidation ratio increasing but increases as vibrational frequency increasing.