DYNAMIC RESPONSE OF COMPOSITE FOUNDATION WITH CFG-PILE IN BEIJING-SHANGHAI HIGH-SPEED RAILWAY

摘要

Dynamic numerical simulation had been done to analyze the composite foundation with CFG-pile by pile caps and different stiffness cushion in low subgrade of Beijing-Shanghai high-speed railway. The distributing rules of dynamic stress of ground surface in the horizontal direction, attenuation rules of dynamic stress and dynamic stress ratio between pile and soil in the vertical direction were studied. It showed that the dynamic stress of pile and soil generally attenuates in depth and attenuation of dynamic stress ratio between pile and soil mostly concentrated into the scope of 5 meters beneath the ground. Moreover application of CFG-pile could effectively reduce the dynamic stress of soil and enhance the dynamic stability of subgrade. Rigid cushion comparatively made uniform distribution of dynamic stress on the ground surface, which homogenized the dynamic stress of upper layer. It will be instructive to control design and construction for low subgrade in BeijingShanghai high-speed railway.