Abstract:

The seismic pile-soil-bridge structure interaction analysis in liquefying ground is a critical problem for seismic design of pile-supported bridge. However, there is no rational numerical model and simplified analysis method to deal with this problem. A numerical model and a simplified method were developed based on Penzien model according to vibrating table test to simulate seismic pile-soil-bridge structure interaction.The simplified method was verified by the computed results for further study.The parameters in simplified method was recommended, which particularly considered the effect of pore pressure on the bearing capacity of sand.The parameter analysis about pile diameters, the initial modulus ratios between pile and soil, the internal angle of sand and the mass of superstructure, was conducted to study the effect on seismic pile-soil interaction. Under the condition of liquefying ground, the recorded and computed results showed that the peak acceleration and the peak displacement of pile decreased and the peak moment on the pile increased as pile diameters and initial modulus ratios increased; the peak acceleration, the peak moment and the peak stress of pile increased when the internal friction angle of sand increased; the peak displacement and the peak moment of pile increased with the increasing mass of superstructure.

Key words: simplified analysis method, seismic pile-soil-bridge structure interaction, shaking table test, liquefying ground, seismic response