斜向槽钢加劲钢板剪力墙弹性剪切屈曲研究

通过对剪切作用下的闭口斜加劲钢板剪力墙进行有限元弹性屈曲分析,研究了肋板刚度比和抗扭抗弯刚度比对斜向槽钢加劲钢板剪力墙剪切屈曲性能及其加劲门槛刚度的影响。通过有限元分析,得到了斜向加劲钢板剪力墙临界剪切屈曲应力随内填板跨高比和加劲肋抗扭抗弯刚度比变化的关系曲线。考虑加劲肋对内填板加劲边转动约束,提出了第二门槛刚度,并给出了具有良好精度的斜向槽钢加劲钢板剪力墙的门槛刚度及第二门槛刚度计算公式。研究结果表明,受压型加劲肋对加劲板的临界剪切屈曲应力提高明显,随肋板刚度比的增大,加劲板的剪切屈曲应力增大,而受拉型加劲肋对板的屈曲荷载提高有限;当肋板刚度比达到第二门槛刚度时,加劲肋可以完全约束加劲边的面外位移和转动。当提高加劲肋的抗扭抗弯刚度比时,能够有效降低加劲肋的门槛刚度,因此,建议加劲肋的抗扭抗弯刚度比不低于0. 307。

Elastic shear buckling of steel plate shear wallsdiagonally stiffened by channel stiffeners

The influence of stiffener-plate stiffness ratio and torsional-flexural stiffness ratio of steel plate shear walls diagonally stiffened by channel stiffeners (SPSWs-DSC) on the shear buckling behavior and threshold stiffness were studied by finite element method. Through analyses, the relationship curves of the critical shear buckling stress of SPSW-DSC to the span-height ratio of the infill plate and the torsion-flexural stiffness ratio of stiffeners were obtained. Considering the rotation constraint on the stiffening edge by the channel stiffeners, a second threshold stiffness was proposed. Formulas for calculating the threshold stiffness and second threshold stiffness of SPSWs DSC was given with good accuracy. The results show that the compression stiffeners can obviously increase the critical shear buckling stress of the stiffened plate with increasing stiffener-plate stiffness ratios, while the increase in the buckling stress of the stiffened plate with tensile stiffeners is limited. When the stiffness ratio of the stiffeners reaches the second threshold stiffness, the stiffeners could completely constrain the out-of-plane displacement and rotation of the stiffened edge. The torsional-flexural stiffness ratio of stiffeners can be improved effectively to reduce the threshold stiffness. The torsional-flexural stiffness ratio of stiffeners is suggested to be no less than 0.307.