关键词: 桩基础, 软弱土层, 振动台试验, 强震区, 动力响应

Abstract: In order to investigate the influence of the different thicknesses of soft soil layers on the dynamic response characteristics of a single pile under different types of seismic waves, the dynamic response characteristics of acceleration, horizontal displacement, bending moment, and pile foundation damage were analyzed by shaking table test. The test results show that under the seismic wave, the restraint behavior of soil around the pile is significantly affected by the thickness of the soft soil layer. The magnifying effect of pile shaft acceleration in soft soil is the most significant. The acceleration magnification factor of the pile top is positively correlated with the thickness of the soft soil layer. The horizontal displacement of the pile top reaches the maximum when the thickness of the soft soil layer is the maximum. The maximal bending moment of the pile appears in the soft soil layer and increases with its thickness. For different soil thicknesses, the maximal bending moment of the pile shaft is less than the design value of bending capacity, and the pile has good integrity. In the seismic design and calculation of pile foundation, the seismic capacity of pile foundation in soft soil layer should be strengthened, and a variety of seismic waves should be selected for seismic checking.

Key words: pile foundation, soft soil, shaking table test, strong earthquake area, dynamic response