Seismic response of high-rise structures by different foundation systems

Dynamic response of pile foundation-structure interaction is reproduced under earthquakes in the shaking table model tests and numerical simulation tests using software MARC. The results show that the effect of deformation of high-rise structures is large because of changed pile-type. The most shear force and overturning moment of high-rise structure in squeezed branch pile interaction system are smaller than those in straight pile interaction system. The deformation energy of the structure is reduced on account of considerable seismic energy in the interaction system of squeezed branch piles and is diffused to the soil through the branch or disk, while considerable seismic energy in the interaction system of straight piles and is converted into deformation energy of the structure, resulting in greater structural damage. At the same time, the results of shaking table tests and numerical simulation show that the squeezed branch pile-foundation has more damping energy, effectively enhances seismic capability of the structure system, and reduces seismic response of the structure under earthquakes. The study is of great significance to the reduction of earthquake damage.