| With the rapid development of high-rise buildings and the diversification of thefunction of buildings, high-rise buildings with transfer structure have been wildly putinto use. Comparing with traditional beam-type transfer structure, Vierendeel trusstransfer structure has great advantage in civil engineering construction. Vierendeel trusstransfer structure can betterly sove the problems of overlarge planes of the section andthe abrupt change of structure stiffness, etc. Meanwhile, the special construction ofVierendeel truss transfer structure help to fix up large pipelines or other equipmentsystem, and the space of the transfer layer can be fully used. Nevertheless, today’stheoretical study on prestress on Vierendeel truss transfer structure is not sufficient.Current national code for design and technical specification does not have clearrequirements for Vierendeel truss transfer structure. Also, more engineering practicalexperiences need to be accumulated. Therefore, it is obviously necessary to study thiskind of structure.Firstly, the essay studies influencing factors of the stress of Vierendeel trusstransfer structure. On the basis of this study, under the current national code and rule fordesign, a prestressed concrete Vierendeel truss transfer structure and a experimentalmodel are designed. Then, quasi-static experiment under the effect of horizontal lowcyclic loading is carried out to study the ductility, energy dissipation capacity, stiffnessdegreadation and lateral deformation of the prestressed concrete Vierendeel trusstransfer structure under infrequent seismic action. And the structural finite elementanalysis software SAP2000is applied in the pushover analysis between the prestressedconcrete Vierendeel truss transfer structure and beam-type transfer structure. Moreover,the progressive collapse performance of the prestressed concrete Vierendeel trusstransfer structure is discussed. Conclusions are as follows.①Prestressed concrete Vierendeel truss transfer structure should follow theprinciples of "enhancing transfer floor and the lower part, relative weakening the upperpart " for design. The transfer columns and bottom chords of truss are importantcomponents of the transfer structure and they should be strengthened. In addition to thevertical web members, the transfer structure have to satisfy the seismic designrequirements of " strong column and weak beam, strong shear and weak bending ". Thevertical web members can only consider the "strong shear weak bending", but not the "strong column and weak beam ". According to the above design principles, the finaldamage of prestressed concrete Vierendeel truss transfer structure is not caused by thelack of seismic capacity of the transfer, but due to the lateral mechanism between floorsin the upper structure.②The displacement ductility factor on the top of Experimental model is5.6, whichmeans that the Vierendeel truss transfer structure has good ductility. However, itselastic-plastic deformation is mainly concentrated in the third layer during the latestages of horizontal loading. This floor become weak floor and therefore the ductility ofthe upper floors in the transfer structure should be enhanced.③After the structure being into the stage of elastic-plastic deformation, theequivalent viscous damping coefficient of the experimental model increases rapidly, andit go up to0.21at the moment of structural damage. All these show that the capacity ofenergy dissipation of the structure is good. The seismic energy is mainly dissipated bythe plastic hinges at both end of beams,which means that the way for energyconsumption is rather ideal.④The vertical web member should be considered as the first line of defense indesign. When removed, the structure must not occur to collapse. The transfer columnsof prestressed concrete Vierendeel truss transfer structure are most importantcomponents for load transmission, and effective measures must be taken to preventthem from destruction which whould lead to the collapse of entire structure. |
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