基于有限元法的方钢管混凝土柱的延性系数研究

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Fig.1 Simplified model of square-shaped CFT column In this paper, the heights of all the square-shaped CFT columns are two meters. The slenderness ratios are respectively set as 20, 30 and 40, which are determined by the width of cross section. The steel ratios are respectively set as 0.08, 0.12, 0.16, 0.20 and 0.24, and they are determined by the wall thickness of steel tubes. The axial compression ratios of columns are set as 0.5, 0.6, 0.7 and 0.8, the value of axial loads are determined by the cross section form and the cross-sectional area of the components. 3.
Abstract: Ductility coefficient is not only an important parameter to assess the ductility performance of components, but also an index to estimate the aseismic behavior of columns. The ductility coefficient is mainly affected by some factors, such as slenderness ratio, axial compression ratio and steel ratio. In this paper, using the general finite element analysis software ABAQUS, authors have numerically analyzed the mechanical performance of square-shaped concrete-filled steel tubular (CFT) columns. Meanwhile, the authors have studied the influence of different factors, including the slenderness ratio, axial compression ratio and steel ratio, to the ductility coefficients. Through the analysis, it is concluded that slenderness ratio is the most effect on ductility coefficient, followed by axial compression ratio and the steel ratio is the least. Keywords: Ductility coefficient; Square-shaped concrete-filled steel tubular columns; Finite element method; Slenderness ratio; Axial compression ratio; Steel ratio
1. Introduction
Concrete-filled steel tubular (CFT) structures, as a type of new composite structure, are widely used in high-rise buildings and complex structures due to their perfect seismic performance and good economic performance. In CFT structure subjected to axial compressive load, the deformation of concrete is restrained by the steel tube, so the compressive strength and deformation capacity of concrete would be higher than plain concrete. At the same time, the steel tube filled by concrete would get higher stability and compressive strength. In a structure, column plays an important role in bearing and load transmission, so it is the key to influence the safety of overall performance structure. Researchers have widely studied the bearing capacity of CFT columns. Gardner and Jacobson [1] have made investigation about the performance of CFT columns under the axial load based on theoretical analysis and experimental results, at the same time the results were compared to the loads allowed by the NBC and ACI recommendations. Knowles and Park [2] have studied the effect of slenderness ratio on the ultimate strength of CFT columns under axial and eccentric loads. Han et al. [3][4] have conducted some experiments on the bearing strength of long and short CFT columns with different slenderness ratios. Ductility coefficient is not only an important parameter to assess the ductility performance of components, but also an index to estimate the aseismic behaviour of columns. Some scholars have studied the ductility coefficient of CFT columns. Han and Tao [5][6] have analyzed the influence of some factors, including slenderness ratio, axial compression ratio, steel ratio, yield strength of steel and compressive strength concrete, to ductility coefficient based on theoretical analysis. Wang and Lu have analysed the effects of slenderness ratio and steel ratio on the ductility of square-shaped CFT frame structure based on the nonlinear finite element analysis model. Based on the analysis above, the authors create the finite element analysis model of square-shaped CFT columns by general finite element analysis software ABAQUS, in which the slenderness
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பைடு நூலகம்
3:1 (2014)
Journal of Materials and Applications
ratio , axial compression ratio n and steel ratio are the three main factors. In this model, the load-displacement curves of CFT columns with different parameters are obtained through the push-over simulation, and the influence of these factors to ductility coefficients are discussed.
Bao-Jie He1, Miao Ye2 1. School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093 2. School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093 E-mail: yemiao0927@