Dynamic response of pile foundation in interaction system

An experimental research on dynamic interaction of pile-soil-structure system was first developed in China.Phenomena of the dynamic interaction of the system were observed,so earthquake damage characteristics between a new type of pile and structure were verified and discovered by shaking table test.Dynamic characteristics and seismic response of the system were studied,and dynamic response of squeezed branch piles was analyzed based on the test data.It was shown by calculation and analysis that the separating and reclosing phenomena occurred between pile and soil under the action of the seismic exciting force,not only revealing that squeezed branch piles were pulled up and pressed down in the course of dynamic interaction,but also explaining and verifing that seismic capability and reduced earthquake damage would be obtained in the dynamic interaction system only when the foundations had greater pulling,pressing and twisting resistant capability.Phenomena of pulling up on one side and pressing down on the other side in the pile foundation were revealed according to reverse direction relation of time-course curve from the corresponding measure points on the sides of pile foundation under seismic action at the same time,and it explained essential reason why the buildings were inclined and toppled in the seismic region.