刚性桩复合地基抗震性能的振动台试验研究

为研究刚性桩复合地基的抗震性能，设计并完成了刚性桩复合地基1:10比尺的振动台试验。试验采用柔性容器这一较新的技术较好地模拟了地基在地震作用下的振动变形。此外，为解决模型与原型难以较好相似的问题，模型中尝试采用了在基础底板施加竖向力、在结构上附加阻尼器等措施。通过大量激振试验，对刚性桩复合地基的地震反应性态、柔性容器的效果等问题进行了研究。结果表明，柔性容器能够较好地解决模型试验的边界问题，刚性桩复合地基具有良好的抗震性能，桩身应变在地震作用下均未达到极限值，上部结构特性对桩身变形有一定影响，振动使土体对基础的约束减弱，但对桩的约束增强。

Shaking table test study on aseismic behavior of rigid pile composite foundation

The aseismic behavior of rigid pile composite foundation was investigated by shaking table tests with a scaling factor of 1/10. In order to better simulate the vibration of the subgrade under earthquake; and flexible wall container, a new technique, was used. In addition, vertical force was applied to the foundation and a damper was installed on the structure in order to have a better similarity in the foundation pressure and in the damping ratio. Through a number of shaking table tests, the aseismic behavior of rigid pile composite foundation and the effect of the flexible wall container were investigated. The results of the tests show that the rigid pile composite foundation has good aseismic performance; the boundary effect of model test could be reduced by the flexible wall container; the strains of the piles did not reach critical value even under quite large seismic wave input; the influence of superstructure on the deformation of piles was not negligible; and the shaking could weaken the constraint of soils to the foundation but increase the constraint to the pile heads.