Comparative Study On Seismic Performance Of Frame-core Tube Structures With Single And Dual Lateral-force Resisting System

In the design code system of China,frame-core tube structure must be designed as a dual lateral-force resisting system,and there exists strict requirements for the secondary lateral-force resisting system of such structure.In other words,the outer frame of the frame-core tube structure must have sufficient lateral stiffness and strength.Ho wever,in the design codes of other countries(e.g.,ASCE/SEI-7 of the United States),frame-core tube structure can be designed as a single lateral-force resisting system.In other words,the outer frame of the structure is permitted to only carry the ver tical load.The seismic performance,collapse resistant capacity,and seismic resilience of single and dual lateral force resisting system are studied in this work in order to investigate the applicability and validity of the systems,the detailed are list ed below:(1)A dual lateral-force resisting system of typical frame-core tube structure is firstly designed following the design codes of China.Subsequently,under the same gravity load(viz.the same concrete consumption),the single lateral-force resisting system of the frame-core tube structure is designed by ignoring shear adjustment of the frame and lowering seismic detailing requirement to reduce the component sectional size of the frame.In addition,an efficient finite element modeling method base d on structural design information,and an inter-story shear force calculating method based on internal force of components are proposed.The effects of different slab and coupling beam modeling methods on the analysis results are also studied.(2)Dynamic properties and material consumption of single and dual lateral-force resisting system structures with heights of 100 m and 180 m are compared,respectively.The seismic performances under different level earthquakes and collapse resistant capacit ies of the two systems are discussed.The relationship between the damages of coupling beams and the contribution of the frame is analyzed,as well as the variation of the seismic force carried by the frame and the damages of key components.Finally,the collapse mec hanisms of the structures with heights of 100 m and 180 m are discussed.(3)Based on the Standard for Seismic Resilience Assessment of Buildings(GB/T 19106-2019),three main processes in building seismic resilient evaluation are introduced: non-linear time history analysis,Monte Carlo simulation and damage state determination.A program for building seismic resilient evaluation is developed according to the introduced methods.Then,a 7-story RC frame structure is taken as an example to illustrate the application of the seismic resilient evaluation methods and program.(4)According to the Seismic Resilience Assessment of Buildings(GB/T 19106-2019),the seismic resiliences of single and dual lateral-force resisting systems with different heights are evaluated.The evaluation results show that the seismic resilience of single system is better than that of dual system.Under the MCE(Maximal considered earthquake),the single lateral-force resisting system structural components and drift-sensitive non-structural components are less damaged than those of the dual system;The acceleration-sensitive non-structural components of the systems show similar damage states.