نوع مقاله : مقاله پژوهشی
نویسندگان
1 مهندس محاسب، مهندسین مشاور، تهران، ایران
2 دانشکده مهندسی عمران، دانشگاه صنعتی اصفهان، اصفهان، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
In this paper, lateral behavior of latticed columns is investigated by the finite element method. I-shape rolled sections of IPE120 to IPE200 are used for latticed column specimens in this study. Shell and solid elements are used for plate sections and welds in the finite element model, respectively. The columns considered are under gravity and lateral loads. Variation of gravity load ratio is investigated. Boundary conditions of the FE models are clamped at bottom and rotation restrained at top. Lateral loads are applied to the columns to cause bending about the non-material axis crossing the latticed side of the column. Non-linear characteristics of these columns including lateral elastic and plastic stiffness values, shear yielding and dissipation of energy (hysteretic curves area), are derived under monolithic and cyclic loading. Based on this study, increasing axial gravity loads, decreases initial stiffness considerably. It also decreases lateral capacity of the columns. Initial stiffness and lateral capacity reduction is considerably affected by axial load ratios under 0.2 (i.e., 20 percent of axial capacity of the column) and after that reduction rate decreases. A super-element that is able to consider behavior of these columns with an integrated section is proposed based on results of the nonlinear finite element analysis. This super-element considerably increases the computation speed by substituting an element with only six degrees of freedom in place of a finite element model with a large number of elements.
کلیدواژهها [English]
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