Abstract Shaking table test on the interaction between the pile group and super highrise building system on liquefiable foundation was conducted to reproduce the liquefaction-induced large deformation of the system in saturated sandy ground. The excess pore water pressure(EPWP) of ground,the natural frequency,the damping ratio,the strain of pile group,the contact pressure at the bottom of pile and the displacement at pile top was calculated and analyzed before and after large deformation. It was shown that the EPWP response in and out of pile group was different. The sand layer liquefied,the natural frequency of pile group decreased and the damping ratio of pile group increased with the raise of peak acceleration. The dynamic response of piles was relevant to both the peak acceleration and the spectral characteristic of earthquake wave. Besides,the peak strain of pile increased upward along pile body so that there were more cracks on the top of pile. The displacement of pile head varied with the seismic behavior. The primary cause of the large deformation of the system was revealed through the phenomenon which two corner piles were pulled up and pressed down alternately under excitation. Consequently,it is effective to improve the anti-seismic capacity of super highrise building-pile group system by strengthening compressive and tensile resistant property of pile and improving the liquefaction conditions of ground.
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