Passive Control Analysis For Seismic Response Of Twin-tower Structures Linked By Sky-Bridge

With the rapid urbanization, the number of the urban citizen is booming, which makes the available land of the city rare. To solve this problem, the high-rise buildings combined with different functions are rapidly developed at home and abroad, among which the double-tower connecting tall buildings are very common.Conjoined twin-tower high-rise structure is one of the more common form. Many researchers have proposed the thought of installing passive vibration isolation devices between the adjacent structures,and using the relative displacement between the structures to consume and absorb the vibration energy to reduce the seismic response of the adjacent structures. A lot of theoretical researches have been done on the adjacent structural vibration control system.But previous research on vibration control of adjacent structures are generally nonconjoined structures which without sky-bridge between the two structures. With the more and more application of twin-tower-connected structures, the passive control analysis of this type of structures is particulaly necessary. Based on the theoretical analysis,numerical simulation method, and funded by the Natural Science Foundation of China(No.51408443), the main contents and conclusions are as follows:(1) The optimum parameters of Maxwell and Kelvin dampers are deduced based on theoretical analysis. The optimazation of the connecting parameters are closely related to the connection parameters of frequency ratios, mass ratios of the two towers, and the mass ratios of the sky-bridge and the main tower, and the damping coefficient ratios between the two ends of the sky-bridge. So through a large number of parametric analysis on different twin-tower-connected structures, and by the comparison of the shock absorber coefficients, the influence of different structural parameters on the control effects are proposed. And some regularity conclusions based on the analysis of the settings of several different parameters are derived.(2) The applicability of the optimum parameters derived by the 3-SDOF in the MDOF is investigated. The results show that the error is within the acceptable range,which implies that the simplified disscussion is feasible. The numerical results by the timedomain also show the effectiveness of the optimization control system.(3) The optimized parameters of the two types of dampers are verified through the numerical examples. The optimal value of the dampers derived by the parametric analysis is only the optimal value in theory. A practical engineering example is selected, by time history analysis, the top floor displacement time history curves and the vibration energy time history curves of the tower 1 and tower 2 and the total vibration energy time history curves of the two towers with and without the sky-bridge and Maxwell dampers or Kelvin dampers are obtained. The results show that, the proposed control schemes of the two types of dampers can greatly reduce the top floor displacement and vibration energy of both the towers which show the effectiveness of the two optimization control systems. It can be found that the control effects of the Maxwell damper are a bit better than that of the Kelvin dampers by comparing the control effectiveness of the dampers with the same case study. Both the top floor displacement and vibration energy of the twin-tower-connected structures connected with the Maxwell damper decrease faster than that connected with the Kelvin damper.