Analysis Of Seismic Behavior For Framed-tube Structures With Outrigger

High-rise and super high-rise buildings have been developed fast with growth ofeconomy. Horizontal load and sideway of structures grow as the height of buildings grows.Setting outrigger, which is widely used in high-rise structures, is an effective way toimprove structures’ lateral stiffness and reduce horizontal displacement. High-risestructure with outrigger belongs to complicated tall building structure in Chinese designcode. Terms to design this kind of structure in code are quite simple. Therefore studyingon force and deformation characteristics of high-rise structures, and extracting specificdesign concept are meaningful.This paper, which is based on basic characteristics of strengthened storeys,applications of structures with strengthened storeys at home and abroad, simplified modelsof structures with strengthened storeys, earthquake resistance and shock absorption andother researches, contains following research work with specific project. Outrigger insolid-web beams, diagonal web member truss, vierendeel truss will be setted in reinforcedconcrete high-rise framed-tube structure with one or two strengthened storeys. Modesuperposition response spectrum method and time-history analysis will be used to studyseismic response of different kinds of outrigger under horizontal seismic load. We can getfollowing conclusions by comparing results of analysis.1.Stiffness and number of outrigger. Large number of outriggers with limit stiffnesscan reduce the negative impacts of force and stiffness mutation while they may controlstructures’ horizontal displacement, which will improve seismic behavior of structure.2.Structure of outrigger. When limit of horizontal displacement is small, outrigger indiagonal web member truss should be considered firstly. When limit of horizontaldisplacement is not that small, outrigger in vierendeel truss will be the choice for seismicdesign. When outrigger with limit stiffness cannot satisfy the requirements of horizontal displacement control, outrigger in solid-web beams should be used.3.Construction measures. Near the outrigger, certain construction measures should betaken for strengthen, which will improve seismic behavior of structure.