Research On Seismic Performance And Design Methods Of New Damping Grounded Tuned Mass Wall

Earthquakes are one of the major hazards affecting the safety of building structures.Structural vibration control techniques can provide additional damping or stiffness to the structure,thereby reducing the structural response under earthquake action and reducing damage.In recent years,energy dissipation and frequency modulation damping techniques have been increasingly used in building structures as research has progressed.A frequency modulated damping device is a substructure attached to the main structure,designed to adjust its own frequency to a frequency similar to that of the main structure,so that when the main structure is excited and vibrates,the substructure moves in the opposite direction to the main structure,attenuating the vibration of the main structure by providing an opposite inertial force.However,the use of tuned mass damping techniques for structural seismic response control is more limited due to the narrow band control characteristics and the space requirements for use.To this end,this paper proposes a design idea for a new Daming Grounded Tuned Mass Wall based on the concept of damped grounded vibrators and damping walls,and carries out research on its damping principles and design methods,mainly as follows.Firstly,the dynamic equations for the single degree of freedom Tuned Mass Damper system(SDOF-TMD)and the single degree of freedom Damping Grounded Tuned mass Damper system(SDOF-DGTMD)under simple harmonic load and earthquake action are established,the dynamic response law is compared and analysed,and the optimal design equations for the SDOF-DGTMD system are obtained.The results of the theoretical analysis show that the steady-state amplitude of SDOF-DGTMD is relatively low compared to that of SDOF-TMD,and its damping effect can be up to 45% better than that of ordinary SDOFTMD.Based on the concept of SDOF-DGTMD,a new type of Daming Grounded Tuned Mass Wall device is proposed,its construction and function are described,a finite element modelling method for the frame-Daming Grounded Tuned Mass Wall system is established,a simplified analysis model is proposed and the dynamic response parameters of the frameDaming Grounded Tuned Mass Wall system are analysed.Secondly,for a real frame structure,Tuned Mass Damper and Daming Grounded Tuned Mass Wall damping schemes were designed and structural response analyses were carried out for different characteristics of earthquake effects.The results show that the Daming Grounded Tuned Mass Wall and Tuned Mass Damper damping schemes reduce the mean inter-storey displacement angle by 31% and 20% respectively compared to the original structure.The time and frequency domain analysis of the elastic-plastic phase of the earthquake was carried out,and it was found that the Daming Grounded Tuned Mass Wall could reduce the damage of the structure under large earthquakes,and the Daming Grounded Tuned Mass Wall had a more stable control effect than the Tuned Mass Damper in the frequency domain.Through the time-frequency analysis,the Daming Grounded Tuned Mass Wall is designed to mitigate the structural damage in the elastic-plastic phase.The results show that a 14% improvement in the control effect can be obtained by optimising the main frequency considering the structural damage under the action of rare earthquakes.Finally,a displacement-based design method for the Frame-Daming Grounded Tuned Mass Wall system is established,and the design process is given.Based on the structural response of the Frame-Daming Grounded Tuned Mass Wall calculation case with different number of storeys under different characteristics of ground shaking,a calculation method for the equivalent seismic action of the Frame-Daming Grounded Tuned Mass Wall is established;based on the numerical results,the axial force distribution pattern of the frame and damping wall connection spring is fitted,and based on the shear force distribution pattern of the frame,the shear force distribution formula of the frame part of the FrameDaming Grounded Tuned Mass Wall is established,and the fitting accuracy is high.According to the design method,seismic response analysis is carried out for a numerical case.The results show that after the addition of the Daming Grounded Tuned Mass Wall,the average reduction in the inter-storey displacement angle of the weak storey under multiple earthquakes is 29.3%;the average reduction in the inter-storey displacement angle of the weak storey under rare earthquakes is 22.9%,and the average damping effect is 6.4% lower compared with that of multiple earthquakes.The design of the damping wall considering the structural damage in the elastic-plastic phase can continue to improve the damping effect under 5% rare earthquakes.