VIBRATION CHARACTERISTICS OF BUILDINGS AND VIBRATION RE-DUC-TION PERFORMANCE OF THE RAFT FOUNDATION NEAR HIGH-SPEED RAILS

Ground-borne vibration induced by high-speed train loads on composite foundation with piles results in vibration of adjacent buildings. This paper built a track-embankment-composite foundation with piles-building three-dimension finite element model to analyze the vibration response of a six-story building, which was at a distance of 30m from the track centerline. Performance of thickness and embedment depth of the raft foundation on vibration reduction was also considered. The results show that the vertical vibration response is predominant and the top floor has higher response than the first floor under the high-speed train load. The vertical dominant frequency on each floor is about 3.5Hz and the horizontal one is about 6.7Hz. The peak value and vibration level of vertical acceleration both decrease with the increase of thickness and embedment depth of the raft foundation, but the decrement lessens. It is useful to increase the thickness and embedment depth of the raft foundation to reduce the vibration of buildings near rails induced by high-speed train loads.