Research Of Seismic Performance Of Complicated High-rise Building With Girder Transfer Floor

Since the mid-1970-s, high-buildings with large space at first story have beentried in practical engineering in China. After a short span of40years, structures withtransfer floor have been widely applied in practical engineering. Among the differenttypes of transfer floor, such as girder, plate, box and truss, the transfer floor of girderis most widely adopted in practical engineering. Therefore, it’s necessary to studywith comprehensive, in-depth and systematic on the structure with girder transferfloor, to provide theoretical foundation and technical support for actual projects ofapplication. In this thesis, mechanical properties and seismic response of a realhigh-rise building with girder transfer floor have been studied, and somerecommendations and conclusions about structural design and seismic structuralmeasures of this kind of transfer floor are proposed.Firstly, the requirement, definition and function of the structure with transferfloor are elaborated and its application in the practical engineering is introduced. Theresearches and applications of high-rise building with girder transfer floor at homeand abroad and development trend of the girder transfer floor are reviewed. Secondly,based on a commercial and residential construction of Hunan Silver Wang Real EstateDevelopment Company, a three-dimensional space model is established using thelarge general finite element software SAP2000, to carry out modal analysis, responsespectrum analysis and time-history analysis of the structure respectively. Thirdly,some influence factors of structural seismic performance are discussed, such as lateralstiffness of the upper and lower floor of transfer girder, the location of transfer girder,and the height of transfer girder. Finally, elastic-plastic time history analysis of thestructure is carried out. The main conclusions are as follows:Through the response spectrum analysis of structure with transfer girder, it isfound that the distribution of story stiffness is very non-uniform along verticaldirection. The sudden change of story shear and story drift at transfer story is easy toform a weak story, which has a great effect on the anti-seismic performance ofstructure. Since the sudden change of story drift and story shear at girder transferfloor may become more serious when the girder transfer floor is set at higher story,the position of transfer girder should be strictly controlled in order to prevent thedisadvantageous effect on the seismic performance of structure. With the increase ofthe height of transfer girder, sudden change of story shear at girder transfer floor becomes more serious, but it has little impact on story drift of the floor under thetransfer girder, while it has great impact on story drift of the floor above the transfergirder. Since the story shear increases with the height of transfer girder, blind pursuitof structure’s partial security with transfer floor will affect the seismic performanceof the whole structure. To control the maximum displacement at the top of structure,some measures can be employed, such as adjusting the position of the transfer girder,the height of transfer girder, and the lateral stiffness of upper and lower stories. Theelastic-plastic time history analysis of structure shows that several indicators shouldbe used to determine the location of week story.