Analysis Of Structural Seismic Responses Of Tall Building With Multi-tower

Multi-tower structure is a kind of complicated structural system. Because of coupling vibration of the towers, the seismic design method of multi-tower building is quite different from the one of usual structural system. Some requests about the seismic design of multi-tower structure which is a kind of complicated tall buildings, are regulated in 'Technical specification for concrete structures of tall building"(JGJ3-2002), but the regulations about the seismic analysis and the constructional measures are not definite and thorough enough to operate. In practice, the number of tower is not more than two, three or more towers are so less designed that less practical experiences are available. Therefore, it is necessary to analysis the properties of seismic response of complicated tall building with three or more towers.In this paper, three-tower building with name of Oriental Tunes Square in Xiamen is analyzed by the international current program SAP2000, considering seismic action in two directions. By structural modeling and calculation, the characteristic of vibration of the multi-tower structure is analyzed, the influences of the rigid ratio of the enlarged base to top tower and translation-torsion coupled effects among several towers are investigated, the inter-story displacement, displacement of the top tower and deformation of tower's base floor in X and Y major orientation under earthquake action are contrasted with those under wind load. At last, the distributing characteristics of stress of transfer plate and of the normal, shearing stress of mostly vertical elements under earthquake action are studied.From above analysis, the thesis gets conclusions as following:(1)The frequencies of multi-tower building are so dense and the coupling in each mode is so evident that the CQC method instead of SRSS should be used to calculate the seismic action effect;(2)torsion effects is distinct between the modes of asymmetry multi-tower structure and it is necessary to take translation-torsion coupling into account;(3)The effect of the enlarged base rigid on the seismic properties is very big, the rigid ratio of the enlarged base to towers in asymmetry multi-tower structure should be designed in a proper range;(4)The distribution of plane rigid is asymmetry because of the asymmetry layout of towers. The torsion effects of structure not only result in large torsion internal force invertical element resisting lateral displacement, but also make large influences on the stress of transfer plate and near floors, thus it is necessary to strengthen those floors.