Analysis Of High-rise Connection Building Dynamic Character And Seismic Response

The high-rise connection structure (HRCS) is a kind of complex structure system which linked with several spatial joining or corridors along its height between double-towers or multi-towers building. Because of the spatial coupled effect caused by connections between the towers, its analysis model, dynamic characteristics, mechanics behavior, failure forms and calculation method are more complex than the common high-rise. According to "Technical specification for concrete structures of building" (JGJ3-2003), the high-rise connection structures belong to complex structures of high building, they should be designed as a strict seismic configuration. The analysis model, dynamic behavior, aseismic design methods, the response analysis under horizontal seismic excitation of the typical double-tower-connected structure, and the series-parallel particle system layer model, are used to discuss the stationary random vibration analysis of influence of connection stiffness on displacement response and sweep frequency vibration test . study in this paper. The main contents are as follows:1. The study of the classification and the calculation models on the HRCS system. Because of the diversity of the structures, their dynamic behaviors and earthquake resistant performances are different; the structure system should be classified firstly and should not be commonly anglicized. On the basis of the structure classification, the adaptability of dynamic calculation models (such as series-parallel particle system layer model, series-parallel rigid-plate layer system model, three-dimensional finite-element model and continuous model) of different connected structures is studied.2. The study of the stiffness matrix, dynamic characteristic on the HRCS system. The inherent cause of the translation-torsion couple existed in the structural system is discussed through the stiffness matrix analysis of the series-parallel connected rigid-plate model of the HRCS. Six kinds of basic vibration modes of symmetric HRCS are deduced by the analysis of free-vibration characteristic equation on the structure. Its physics essential that the participating coefficient of vibration mode of the HRCS is different from one of the common single tower building is revealed through the analysis of the participating coefficient of the vibration mode. The principle of selecting vibration modes for the structural system is also given. At last, the change of the self-vibration period on the connection while the connection position was changed through several examples.3. The aseismic design method and the analysis of seismic response on HRCS. The paper simply illustrates the aseismic design method on HRCS, and the method of model decomposition is feasible for HRCS. Using the above calculation models, the paper researches the seismic response under one or two dimensional earthquake excitation through several examples of the HRCS, and discusses the dynamic response of different structure systems under the horizontal seismic excitation and the influence of the displacement and internal force while the joining positions were changed at details.4. Stationary random vibration analysis of HRCS. The common method and pseudo-excitation method are simply discussed, based on pseudo-excitation methods which are invented by LIN Jia-hao, firstly calculate the spectral value of monomer in connected position, and regard the spectral response from the monomer as the stationary coherent random excitation at connecting point, and find the analytical expression of displacement response variance under stationary random response diaphragm, and discuss the change of displacement response variance detailed with the connectors' different stiffness and damping ,and find the change of displacement response variance is very obvious while the connectors' different stiffness and damping are changed.5. Sweep frequency vibration test study of HRCS. Introduced simply the design and making of a test model, the arrangement of the accelerometer sensor, the layout and selection of connection, and the S AP2000 finite element model was given. From the three band the natural frequency of structure, top-rise accelerometer and displacement of the top-rise, the test results and the finite element analysis results were compared, so it is concluded that although the test data of sweep frequency vibration and the results of finite element analysis have some differences, with the change of connection, its displacement of top floor and response to the change of acceleration are same basically.