Seismic Performance Analysis Of High-rise Hybrid Structures With Replaceable Energy-dissipated Coupling Beams

With the improvement of economic development,as well as the requirements of function,the(ultra)tall hybrid structure has been widely used in all parts of the country,with its seismic capability and flexible space function.However,some of them are in intensity areas.Earthquake damage investigations and shaking table tests show that the hybrid structure damages mainly concentrate in the coupling beam,so the energy dissipation capacity of the coupling beam and applcation to hybrid structures are extremely important.This study can provide technical support for the damage controlled and rapid repair of hybrid structural system,and for the wide application,further for relevant seismic design standard.The research mainly completed the following work:1.On the basis of research about metal damper both abroad and native,an optimized damper is provided by elastoplastic mechanics theory to relieve the stress concentration,and the formula for design is deduced further.16 specimens are examined by pseudostatic testing,and the design formulas are checked.Furthermore,the plastic capacity and axial deformation capacity are studied in the following.From the research,the optimized dampers can yield simultaneously along the damper profile so as to all cross sections are in plasitc,and relieve the stress concentration.2.Based on the research of optimized damper,the coupling beam is designed to control the damage of core tube.And the formula of strength and stiffness are derived.4 specimens are designed,among them 2 floor are move up 3cm.By the pseudo-static testing,the design formulas are checked,plastic capacity and damage mode are studied.The elastoplastic constitutive model is regressed by experimental data.By use of the finite element software PERFORM-3D,the constitutive model is checked.Through site timing,all of the disassembly and disassembly process can be finished by 1 hour.So the research provides a theory for the following study on energy dissipation.3.For the numerical model of finite element,the quasi-static test of a 6-story core tube is simulated by the PERFORM-3D.According to chapter 3 design methods of coupling beam,the six layers of steel reinforced concrete core tube is designed by shock absorption.From research,the coupling beam can increase 2 times of structure energy dissipation,and 2 times of coupling beam energy dissipation ratio.And reduce the damage to other components.The research provides the basis of shock absorption for later mixed structure design and numerical simulation analysis.4.For the accuracy of the numerical model,a vibration table test with 1:10 scale of a 17-storey mixed structure is simulated by the PERFORM-3D..According to the design method of energy dissipation in chapter 3,the hybrid structure is applied by the energy dissipation coupling beam.The research indicates that,according to the limit bearing capacity is 0.8 times as the ultimate bearing capacity of the energy dissipation coupling beam,the greatest capacity of the coupling beam can be carried out,and effectively reduce the core tube wall damage,and can reduce drift and top displacement.Furthermore,the seismic performance of the energy dissipation structure can be improved by 1 grade under the design earthquake.In this paper,the research to the high-level mixed structure can provide a method of energy absorption design and seismic performance evaluation,and can ensure the mixed structure seismic safety and function of recoverability.