关键词: 地震动持时压缩, 振动台模型试验, 加速度, 液化

Abstract: In the shaking table model test on liquefiable sandy soil, the duration, frequency, energy and other characteristics of ground motion have changed after the seismic record time is compressed according to the time similarity ratio, and it will have a significant impact on the dynamic response of liquefiable foundation under seismic loading. The time compression ratio is the only variable in this series of shaking table model tests, and the effects are analysed by the characteristics, such as macroscopic phenomena, acceleration, pore water pressure. The effect of dynamic response of liquefied site in the shaking table tests with seismic record after time holding compression is researched in this paper. Results show that when the PGA of the input ground motion is similar, liquefied site may not be liquefied if the seismic record time is compressed. The longer the duration, and the greater the energy of the ground motion, excess pore water pressure accumulates rapidly, and the phenomenon of soil liquefaction and the filter isolation effects are obvious. According to the results of the tests, it is suggested that the original ground motion could be directly adopted by the shaking table tests regarding liquefaction as research objective.

Key words: ground motion duration compression, shaking table test, acceleration, liquefaction