Key issues in design of complex multi-tower connected structure of Taikang Financial Center
Taikang Financial Center high-rise building is a three-tower connected structure with a height of 237.3 m.The slenderness ratio of each single tower exceeds the provision limit considerably and the eccentricity of plans are significant,hence the single tower structure is difficult to establish.Therefore,three connecting bridges are set up on the 18th,29th and 40th floors to connect the three towers as a whole.The torsional stiffness and lateral stiffness of the connected structure are evidently enhanced.The forces in the vertical components become more average under gravity and the lateral displacements of structure become extensively lower under lateral load.The key issues of complex multi-tower connected structure are studied such as stiffness change,torsional effect,influence of construction sequence and joint design.The results reveal that the multi-tower connected structure has huge stiffness change,resulting in the existence of weak floor upon the top bridge,which needs to be strengthened in design.The torsional effect of the building is not obvious because of the integrality and the high torsional stiffness.The construction sequence has an evident influence on mechanical behavior.The construction scheme of the tower structure above the connecting bridge being constructed before the connecting bridge is adopted,but the number of leading floors does not exceed 5 floors.Finite element analysis of key joints of the bridge is performed,showing that the behavior of joints can meet the seismic performance objective.