Shaking Table Tests On Dynamic Interaction Of Frame-core Tube Structure And Subgrade

With the development of social economy, the demand for buildings becomes more diversified, and lots of constructions develop to the air and underground, all of these promote the development of high-rise buildings. In this process, the interaction problem becomes more and more prominent. In order to study the rationality and seismic safety of the design of high-rise building structure, dynamic interaction of structure-foundation become an important issue that must be considered in many projects. Shaking table test become one of the most common methods to study the dynamic interaction with the advantages of low cost, strong controllability and repeatable use.Shaking table test of a super high-rise frame-core tube structure was carried out using similarity theory, to study the vibration characteristics and earthquake responses of structure-soil interaction system. Vibration characteristics and dynamic responses were obtained by calculating and analyzing the mode shapes and maximum displacement of each floor. Meanwhile, the influence of interaction on structure and the earthquake responses of structure on rigid foundation were acquired comparing the model test of the structure which was built on rigid foundation and interaction system under same load condition. The main results are as follows:With the increase of input acceleration peak, the frequency decreases and the damping ratio increases of the structure in interaction system, which show similar laws to the rigid foundation system except for smaller changes in amplitude. There are remarkable rocking and swing at the foundation of interaction system, but at smaller amplitude. The seismic responses of the structure were not only related to the input acceleration peak but also to the form of seismic wave. Dynamic interactions amplified the earthquake action in small earthquakes, and weakened the earthquake action when the intensity of earthquake reached a certain size.The results showed that the dynamic interaction had great influence on both vibration characteristics and dynamic responses of upper structure. Interaction between structure and foundation must be considered in the design of building structures especially in high-rise structure. The results will be useful for the design of super high-rise buildings and study on the dynamic interaction.