The Research On The Mechanical Performance Of Steel-concrete Hybrid Structures

By the rapid developing of the economy in our country, the high-rise building becomes more and more familiar all over the place. As one new-style structure system, the steel-concrete hybrid structure combines the excellence of the steel structure with that of the reforced concrete structure. So it has well performance on stiffness and carrying capacity, and used widely in high-rise building, especially in skyscraper. Nevertheless, the researches of steel-concrete hybrid structure draggle its application in the practice of engineering greatly. As it is, the analysis and researches of the mixed structure of the steel frame-concrete core tube have been done in this thesis, which contains the following contents:In the first chapter, it introduces the definien and developing of high-rise building simply. It ticks off the common structure systems of the high-rise building and analyses its mechanical performances. At the same time, the definien and characters of high-rise mixed structure is introduced also. There are some problems need to be solved in the actual research of the high-rise mixed structure. The background and main contents are introduced in this chapter, too.In the second chapter, the characteristic of various elements and the constitutive relation of the main material, such as concrete and steel, chosen in the common finite element analyses for the high-rise mixed structure in the project are introduced in detail. The basic principle about the calculation of the internal force of the steel-concrete hybrid structure, and short-cut calculation methods contains the distribution principle between the steel structure and the reforced concrete structure under horizontal and vertical loads are expatiated in this chapter. At last, the pushover method in high-rise mixed structure is introduced.In the third chapter, the modelings are done to the mixed structure of the steel frame-concrete core tube by the current finite element analyses software ETABS and current design software PKPM. By two different models, the influences to the static and dynamic properties, such as natural period, displacement, moment and the shear force in base, of the mixed structure as the changes of the thickness of the floor and tube are discussed. At the same time, the difference and the reliability of these two models as well as their reasons are compared and discussed, too. The interrelated conclusions by the corresponding studies are gotten for the future projects. In the forth chapter, the load, displacement, period, angle and so on of a mixed structure of the steel frame-concrete core tube in one big city as a project are analyzed and discussed. At last, the curve of the shear force in base-top displacement is attained and the seismic performance and ductile performance are discussed by the pushover analysis.