Shaking Table Test And Analysis Of Model Of Mega-frame Structures With Vibration Absorption Substrucure

Mega-frame structure with vibration absorption structure is a new type of structure system,which combines mega-frame structure with damping control.The isolation bearings are arranged between the substructure and the main structure so that the substructure becomes a damping oscillator,which is similar to the tuned mass damper.On the one hand,numerous studies have shown that the mega-frame structure with vibration absorption substructure can effectively reduce the dynamical process of construction under the earthquake,but on the other hand,the large-scale seismic simulation test of the shaking table is insufficient because of the complexity of the structural system.Based on the theoretical analysis of parameter optimization of the mega-frame structure with vibration absorption structure and the difference of the vibration absorption effects caused by the number and location of the vibration-damping substructures,seismic simulation shaking table test research was carried out in this paper by comparing the structure of the general mega-frame structure(non-damped structure)and the mega-frame structure with vibration-attenuator structure(single damped structure and thriple damped structure).The main conclusions are shown as follows:(1)In order to conduct rational design and analysis on the shaking table model,a refined model was established for the test structure by MSC.Marc finite element program,and amplitude modulation earthquakes was input for nonlinear analysis.The results indicated that the arrangement of vibration-damping substructure can prolong the period of the structure.The period increased with the number of vibration-damping substructure.The floor displacement of the main and sub-frame of the single damping structure and the three-damping structure,the absolute acceleration of the main frame floor and the top layer of the sub-frame were less than the non-damping structure.Damping effect of the thriple damped structure was better than single damped structure.(2)For the purpose of ensuring the accuracy of the later test results,shear performance tests were conducted on five sets of isolation lead-rubber bearings.The results showed that the yield force and post-yield stiffness of the isolated bearing were close to the design value,and the performance of isolated bearings was relatively stable.(3)In order to demonstrate the effect of the number of vibration-damping substructures on the dynamical process of mega-frame structure with vibration absorption substructures.The non-damped structure,single damped structure and thriple damped structure test models were designed and tested on the shaking table.The results indicated that under the action of El_Centro wave and artificial wave,the floor peak displacement,story drift and absolute acceleration response of the main frame with single-damping structure and triple-damping structure were less than those of non-damping structure.The top displacement of sub-frame had also been reduced to some extent.(4)The accuracy of the shaking table test and theoretical analysis were verified by comparing the calculated value with the valueof the test.At the same time,the errors between both of them could be related to the three models which were loaded in sequence.The structural stiffness was degraded.Otherwise,each model was independent in the finite element analysis.The error of processing and mounting of the support and the error of the test equipment were related themself.