含可更换剪切型耗能梁段的组合钢框筒截面尺寸预估方法探究

含可更换剪切型耗能梁段组合钢框筒可克服传统钢框筒延性差和震后修复困难的缺点,有助于其在较高烈度区的应用。高层钢框筒用轴压比和等效实膜筒法确定的构件截面尺寸较粗糙,需反复试算和调整。为方便所提出的组合钢框筒结构的初步设计和抗震性能研究,给出了该新型结构各构件截面尺寸的预估方法,并通过组合钢框筒算例利用双向地震弹塑性时程分析方法验证了所提出预估方法的有效性;同时比较了罕遇地震下钢框筒与组合钢框筒的层间位移角、楼层位移、基底剪力、剪力滞后效应、塑性铰分布。研究表明:所给出的构件尺寸预估方法具有较好的效果,能够实现罕遇地震下塑性变形集中于耗能梁段,便于震后修复和功能恢复;罕遇地震下,相对传统钢框筒,组合钢框筒的各楼层的弹塑性层间位移角、楼层位移均明显减小,且其水平主向的基底剪力峰值明显减小,具有良好的减震效果,此外其角柱的轴力绝对值明显降低,减小了剪力滞后效应。

Study on the Section Dimension Estimation Method of Composite Steel Framed-Tube Structure with Replaceable Shear Links

The composite steel framed-tube structure with replaceable shear links can overcome the shortcomings of the traditional steel framed-tube structure,such as poor ductility and difficult post-earthquake repair,which is helpful for its application in higher intensity areas.The section dimension determination of members of high-rise steel framedtube structure is not effective by axial pressure ratio and equivalent membrane tube method,which needs repeated trial calculation and adjustment.In order to facilitate preliminary design and seismic behavior research of proposed composite steel framed-tube structure,a section dimension estimation method for each component of the new structure is proposed,and its validity is established through composite steel framed-tube structure examples using bi-directional seismic elastic-plastic time history analysis method.At the same time,inter-story drift angle,story displacement,base shear,shear lag effect,and plastic hinge distribution of traditional steel framed-tube structures and composite steel framed-tube structures under rare earthquake are compared.This study shows that the proposed estimation method has a good effect,and can concentrate plastic deformation on shear links under rare earthquake,which is convenient for post-earthquake repairment and functional recovery;under rare earthquake,in comparison with traditional framedtube structure,elastic-plastic inter-story drift angles and story displacements of composite steel framed-tube structure are significantly reduced,and its base shear peak value in the horizontal principal direction is obviously reduced,which has a good shock absorption.In addition,the absolute values of axial force of its corner columns are significantly reduced,which reduces shear lag effect.