Steel - Concrete Composite Columns In High-rise Buildings

With the development of high-rise and long-span building, columns have to bear higher and higher axial load. Based on the investigation to damage caused by earthquakes, people have realized the design of columns play a key role to prevent the collapse of building in strong earthquakes. To meet this need, the columns are required to have high strength as well as high ductility. This paper summarizes the present research in heavy load-carrying columns and analyses the work mechanisms and characteristics of steel reinforced concrete columns and concrete-filled steel tubular columns. Then a new design model for heavy load-carrying columns is established. This column which has the main advantages of the steel reinforced concrete column and the concrete-filled steel tubular column is called as circular steel tubular column filled with steel-reinforced concrete. This kind of columns can be used in high-rise buildings because of their high load-carrying capacity and excellent ductility. Referring the application of composite steel-concrete columns in high-rise buildings, the major contents are summarized as follows:Firstly, based on the test results of concentrically loaded circular steel tubular columns filled with steel-reinforced concrete, work mechanisms of this composite column are studied. A calculation equation for the strength prediction of the composite columns is proposed. Secondly, A model calculated the strength of compression-bending composite columns is established. Finally, the problem about beam-column joint is mainly studied and some design methods are suggested in this paper. Meanwhile, the author designs the columns on the ground floor of ChunLiu High-Rise Building. The advantages of circular steel tubular columns filled with steel-reinforced concrete are discussed by comparison to reinforced concrete columns.From the above analysis, we can conclude that circular steel tubular columns filled with steel-reinforced concrete which have high load-carrying capacity as well as excellent ductility can be used widely especially in the buildings of strong seismic intensity zone.