| Reinforced mega-frame structure is a structural system which is composed of major frame and sub-frame. The major frame is made of large structural elements such as giant beams and columns. The giant beam may be one or two-layer Height, which can be solid-web or truss girder. The giant column can be solid web column or giant tube. This structure has a high integral rigidity and clear force transmission. It also gives full play to high-strength concrete in material performance with good economic and promising developments. In this paper, with the support of Natural Science Foundation major research project " super high-rise mega-frame structure and energy of seismic response analysis of research ", according to the concrete standard and Technical Specification for Concrete Structures of Tall Building reinforced concrete, mega-frame structure of a 201-m was designed through the software PKPM by the group members. A reduced-scale geometric ratio of 1/25 scale model of shaking table was designed compared with the prototype. According to the test results, detailed experimental study and theoretical analysis are completed as follows:(1) This paper described three similar theorem of similarity theory and analyzed how to use similarity theory, such as the general similitude law and dimensional method, to design scale model for shaking table test.(2)It is proved that shaking table test can indicate the seismic requirement of structures by studying the changes in frequency and stiffness of several shaking table test data of high-rise buildings.(3) According to the mega-frame structure designed by the research group, a reduced-scale model was designed to verify the seismic effects of mega frame,whose geometric ratio is 1/25.The shaking test is completed in State Key Laboratory for Disaster Reduction in Civil Engineering at Tongji University. Moreover, the paper finish the design, production, the ground motion selection, calculation of additional quality, white noise conditions Choose in detail.(4) This paper described the dynamic response under 7 frequently occurred and basic intensity 7 earthquakes as well as intensity 7 seldomly occurred earthquakes, the results show that the design of mega-frame structures according to the relevant specifications can meet seismic requirements. In addition, the damage of the structure model was analyzed based on MAC method.(5) In order to explore the damping effect of Mega-frame structure under the tuned mass damper effect, a TMD system was installed in the top of the scale model.The test results of the damping and non-damping structure shows that TMD damping effect is more obvious under El Centro ground motion.(6) This paper analyzes structures displacement reaction under ground motions of the different frequencies. Theoretical and experimental studies showed that the top displacement reaction of the structure mainly caused by the signal within the range of 1/2～2 twice the first structure frequency under El Centro, Chi Chi and Wenchuan earthquake ground motion.(7) The modal analysis of mega-frame was done based on the test data. The structure frequency is obtained based on the peak method, the Fequency and Response Function is obtained by the power spectrum method, dampings are obtained through the least square method of the complex modal. Based on the peak of Averaged Normalized Power Spectral Density of displacement signal, the severity of the injury of the structure in which conditions can be more accurately determined.(8) Based on the numerical simulation study of the mega-frame test model by the ABAQUS software, the applicability of the numerical simulation in mega-frame structures was prived. At the same time test and numerical simulations show the TMD (Tuned Mass Damper) is outstanding. |
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