Research On Passive Control Of Symmetric Double Tower Structures With Chassis

More and more high-rise buildings appear in modern cities due to dense population and limited land.Some high-rise buildings are designed as two-column structure with two substructures due to functional requirements.The possibility of damage to the tower structure is high under a major earthquake.The research on the double tower with chassis is mainly focused on the asymmetric structure now.The energy absorbing device is connected between the adjacent tower structures for consuming the energy,so that a part of the seismic energy can be absorbed and the collision between the structures also can be avoided.However,the seismic research on the symmetrical tower structure is relatively rare,and the proportion of such buildings is relatively large.Therefore,it is of great significance to focus on the research on vibration control of symmetrical tower structures with chassis.This paper comprehensively applies theoretical analysis,numerical simulation,finite element analysis and verification methods in the following aspects:(1)Simplified the structure of the symmetrical double tower with chassis to 2-DOF system,the Kelvin model and Maxwell model for the passive damper is selected,and the optimal parameters of the two passive dampers based on the energy minimum theory is obtained.Through numerical analysis,it is found that the proposed passive damper can effectively reduce the displacement response of the 2-DOF system by using the optimized parameters,and proves the effectiveness of the proposed optimization parameters.When adopting the same control strategy,the displacement control effect of the Maxwell damper is better than that of the Kelvin damper,and for each passive damper,the control effect of the second strategy(the minimum total structure energy of the control structure)is better.(2)The optimal damper parameters of Kelvin damper and Maxwell damper are related to the characteristics of the structure itself.The mass ratio m and frequency ratio b affect the structural energy.When other parameters are determined,the structural energy increases with the frequency ratio b Increases and have the best control effect near the mass ratio m=0.5.(3)For the M-DOF chassis with symmetric double tower system,it is found that the peak displacement,maximum energy and interlayer displacement of the M-DOF system are effectively reduced when the passive damper adopts the optimized parameters,which indicates that the chassis is symmetric based on 2-DOF.The analytic expression of the optimized parameters of the passive damper between the two tower structures is also applicable to the M-DOF structural system with a chassis symmetric double tower.when adopting the same control strategy,the control effect of Maxwell damper is better than that of Kelvin damper,and for each passive damper,the control effect is better when using strategy 2(minimum total energy of control structure).(4)The symmetrical double-tower model with chassis is established by the finite element software ETABS.The control effect is also obvious when the passive damper adopts the optimized parameters.It shows that the analytical expression of the optimized parameters of the passive damper based on 2-DOF is suitable for the symmetric double with chassis.In the actual engineering of the tower building,the control effect law and numerical analysis of the passive damper in the finite element analysis are consistent,which proves the feasibility of the optimization parameters based on the 2-DOF system in the actual engineering of the symmetrical double tower with chassis.