Research On Hybrid Passive Control Vibration Mitigation And Key Influencing Factors For Super High Structures

Since most of the provisions of the current specifications are researched and formulated with medium and short period ordinary structures,as for the design longperiod super high-rise structures,problems such as distortion of long-period response spectrum,unclear quantitative indicators of overall safety margin of structures,insufficient rationality of control design indicators such as shear weight ratio,unclear relationship between different indicators and responses,unclear relationship between elastic design and elastic-plastic response,and the unclear relationship between different indexes and responses,the unclear relationship between elastic design and elastoplastic response,and the unclear rules of structural plastic development and instability collapse mechanism are encountered in the design process of long-period super high-rise structures,resulting in the inability to obtain the optimal structure in the design process of super high-rise structures.With the gradual maturity of structural design practice in China,engineers have put forward the need for further understanding and demonstration of the design of super high-rise structures,especially the design of energy dissipation and vibration reduction.In this paper,the key influencing factors of the hybrid vibration reduction design of super high-rise structures under wind and earthquake excitation,such as load input parameters,damping system parameters,key design control indexes,and key performance control principles,are analyzed.The load input parameters include the response spectrum,and the damping system parameters include the additional damping ratio of viscous dampers,TMD mass ratio,and the yield force coefficient of metal dampers.The key design control indexes include the shear weight ratio and the stiffness weight ratio.The key performance control principle is the relationship between elastic design and plastic response.The seismic response control method considering elasticplastic performance and the design method of elastic-plastic instability collapse prevention are proposed.The necessity of simplified model ID A incremental dynamic analysis to verify the performance of super high-rise structures is demonstrated.A simplified method of sheet model of mega frame concrete structure is proposed,and the analysis and conclusions in this paper are verified with the simplified model.The main research contents and achievements of this paper are as follows:(1)Through parameter analysis,the response law of TMD and viscous damper mixed application under different main structure and substructure system parameters is studied,and the synergetic loss factor is proposed,which can more accurately reflect the use efficiency of the damper when mixed vibration reduction is performed;(2)The characteristics of the seismic response spectrum are studied,and the method of setting the shape and parameters of the seismic response spectrum that can be applied to the seismic design of super tall buildings is proposed.The quantitative relationship between seismic elastic design and elastic-plastic performance is analyzed,and the improved Kasai method damping design formula is proposed,which extends the prediction range of structural response from elastic stage to elastic-plastic stage;(3)The key influencing factors of structural design,such as super strength coefficient,are studied.A multi-stage progressive yield mechanism and an application method that can provide the stiffness of the main structure after yielding are proposed.This method can improve the anti collapse and instability ability of the building entering the elastoplastic stage,and the theoretical analysis of the anti collapse and instability design of the elastoplastic structure is completed;(4)A simplified method of super high-rise mega-column core wall concrete structure model is proposed,which can effectively improve the analysis efficiency,reduce the complexity of IDA analysis of super high-rise structures,and provide an effective means for the analysis of key design variables of hybrid control of super highrise structures in the scheme research stage.This thesis provides a theoretical reference for hybrid vibration reduction design of super high-rise structures,thus providing a technical path for systematically enhancing the performance of super high-rise structures.