Analysis Of Dynamic Characteristics And Seismic Responses Of High-rise Building

Analysis of structure dynamic characteristics and seismic responses is an effective way to investigate structure seismic behaviors, and can provide some important gist for structure design and performance evaluation. However, there are few studies focusing on the dynamic characteristics field test of high-rise buildings especially the tube-in-tube structures in presently research. In this paper,a few positive conclusions have been gained by comparing the results of field tests and numerical simulation calculation.The practical project–ShanXi information tower was regarded as the research background in the paper. The dynamic characteristics were obtained through field test method and finite element simulation calculation method respectively and the causes of difference were analyzed in the two methods. Moreover,the further analysis of seismic response was made based on the analysis of dynamic characteristics. The contents and conclusions of this paper are as follows:1. According to the research of appropriate testing scheme and analysis method, we successfully tested dynamic characteristics of the shanxi information tower and obtained the first four ranks horizontal frequency and the vibration mode in X and Y direction, the first two ranks torsional frequency and the first ranks vertical frequency of this structure. All of these can provide guidance for other building's design and information for the safety evaluation of the structure in the future. At the same time, the foundation for further dynamic analysis of this building was laid.2. The finite element model was established according to the practical size of the structure through ANSYS and frequency, vibration mode and model participation coefficient were obtained by doing modal analysis.3. Both results from experiments and calculations show that: the first vibration mode is horizontal vibration in X direction, the second vibration mode is horizontal vibration in Y direction and there are no significant differences in the results of the first-two period. According to this, we can make a conclusion that rigidity in X direction is a little stronger than that in Y direction, stiffness distribution of upside structure is relatively homogeneous and the structure have well integer performance.4. Mode–superposition response spectrum method was also taken to obtain the seismic response in X and Y direction together with each story deformation, which provide gist for further seismic analysis of this structure.