Exposed to fire on three sides of the rectangular steel tubular column of fire resistance
|School||Harbin Institute of Technology|
|Keywords||Rectangular CFT In Fire Temperature field Fire resistance|
CFT with its high capacity, ductility, good toughness, easy construction and fire resistance and good performance in many high-rise buildings has been widely used. Rectangular steel pipe concrete structure concrete column as an important component in the form, in addition to both the above advantages, but also because of its bending stiffness, the node structure is simple and highly structural engineers of all ages. Fire resistance of the structure is to determine whether the structural safety of the important factors that the existing steel structure fire resistance of concrete norms or rules, such as \\Since the non-symmetric temperature distribution, degree of deterioration of the material member section is asymmetric, resulting in the center section of the material strength is shifted, so as to form an additional eccentricity; addition, asymmetric temperature distribution pillar exposed surface causes swelling deformation, unexposed surface swelling deformation, resulting deflection to the exposed surface of the additional deformation. In summary, rectangular steel concrete columns under fire and surrounded on three sides by the fire, there are many differences, it is necessary to fire on three sides of rectangular steel fire resistance of concrete columns were studied. Accordingly, this article on three sides by fire rectangular steel concrete columns were studied and finite element analysis, specifically including the following three parts: (1) three sides by fire rectangular steel concrete column test research and analysis carried out two three sides by fire a fire surrounded by a rectangular steel tubular column full-scale fire resistance test, measured by the fire of the cross section of the whole process of key locations component temperature, axial deformation and lateral deflection, won three sides by fire rectangular CFT column failure mode, based on experimental data, analysis of load ratio and fire resistance to fire boundaries were investigated. (2) three sides by fire rectangular steel tubular column finite element analysis based on ABAQUS established can be used to analyze three sides by fire rectangular steel tubular column temperature and fire resistance of the three-dimensional finite element analysis model, and has been related to experimental verification. Then fire on three sides by rectangular steel concrete column stress mechanism in depth research, including rectangular steel concrete column temperature distribution, failure mode, stress and strain distribution and development. (3) three sides by fire rectangular steel tubular column fire resistance parameters analysis was carried out on three sides by fire rectangular steel tubular column fire resistance parameters analysis, including heating time, cross-sectional dimensions, steel ratio, the protective layer thickness and cross-section aspect ratio on the temperature field were studied; load ratio, cross-sectional perimeter, slenderness ratio, steel ratio, steel strength, compressive strength of concrete, load eccentricity, cross-sectional aspect ratio and the protective layer thickness on the fire resistance of law; proposed to consider the different fire back boundaries in Fire fire resistance of rectangular steel tubular column simplified formula in order to provide a reference for engineering applications.