关键词: 抗滑桩, 桥梁基础, 振动台模型试验, 卸荷效应, 频段耦合效应

Abstract: As the research demands develop in the seismic reinforcement of bridge foundation on slope in engineering practice, a shaking table model test of bridge foundation on a slope reinforced by the front and back row anti-slide piles is introduced, in which the dynamic loading is applied in form of sine waves with different frequencies and peak accelerations. This study emphasis on the analysis of mechanical responses of the bridge foundation and anti-slide piles, and the developing process of landslide and dynamic response performance. Results show that the front and back row anti-slide piles should keep a proper distance to the bridge foundation, so that the mechanical responses of bridge pile foundation are more reasonable. As the dynamic load of upper structure affect bridge foundation greatly, the strain decreases along pile depth and the strain attenuation is related with soil resistance. When the back row anti-slide piles are cracking, the pile strain decreases significantly and the unloading effect appear in soil pressure behind piles. However, there is potential bearing capacity on pile strength. The landslide failure starts in the section dangerous in stability. The frequency-band coupling effect produce gradually before the back row anti-slide piles reaching the limit loading in vibration, and then the unloading effect take over after the limit loading state.

Key words: anti-slide pile, bridge foundation, shaking table model test, unloading effect, frequency-band coupling effect