十字加劲钢板剪力墙的抗剪极限承载力

我国《高层民用建筑钢结构技术规程》规定了钢板墙剪切弹性屈曲不先于剪切屈服,其明显的不足是没有利用板的屈曲后强度,同时弹性屈曲也不能作为结构在弹塑性阶段的设计指标。本文应用板的大挠度弹塑性有限元方法对十字加劲方形钢板剪力墙的屈曲后性能和极限承载力进行了系统的研究,并在大量数值分析的基础上,提出了以板的平均剪切应变相应的剪应力作为钢板剪力墙承载能力的极限状态,以达到利用薄板屈曲后强度的目的,进而提出了钢板剪力墙承载力的设计简化计算公式及钢板墙侧柱刚度阈值的计算公式,供设计参考。数值计算结果表明,影响钢板墙抗剪性能主要有三个参数:板高厚比、肋板刚度比和边柱刚度。

Ultimate shear-carrying capacity of steel plate shear wall with cross stiffeners

The steel plate shear wall (SPSW) is designed to prevent buckling in current code, which ignores the post buckling strength and elastic plastic behavior. In this paper, the post buckling behavior of steel panel with cross stiffeners was investigated theoretically under shear loading based on the large displacement elastoplastic theory of plate, where the steel panel was framed by pin connecting square steel frame. Three most important parameters were employed in the analysis including panel slenderness ratio λ, stiffness ratio of stiffener to panelη and column stiffness β. Numerical results were presented by using FEM structure analysis program, namely the ANSYS package. The stiffened and unstiffened steel panels behaved high load carrying capacity and good ductility, and stress τ1 corresponding to average shear strain γ=γy was suitable to predict its ultimate load carrying capacity, where the post buckling strength of the panel was involved to increase its shear carrying capacity. Column stiffness had great influence on the post buckling behavior of steel thin walled panel, while it had little influence on that of thick walled panel. The stiffness and post buckling behavior of thin walled panel with weak columns can be greatly improved by setting η to 30. The formulae for determining ultimate load of steel plate shear wall and threshold value of column are proposed.