Displacement amplification factors for steel eccentrically braced frames
Displacement amplification factors for steel eccentrically braced frames
复制标题
钢偏心支撑框架的位移放大系数
DOI：
10.1002/eqe.2463
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发表时间：
2015
影响因子：
4.5
通讯作者：
C. Topkaya
中科院分区：
文献类型：
--
作者：
Ahmet Kuşy?lmaz;C. Topkaya
杆件的弹塑性变形能力是影响钢偏心支撑框架设计的重要因素。用连杆转角来描述非弹性连杆变形。杆件转角通常是通过利用设计层位移来计算的，而设计层位移又是通过用位移放大系数修正弹性位移来计算的。本文对ASCE7-10中给出的EBF位移放大系数和用于计算杆件转角的刚塑性机构进行了数值研究。以层数、间隔层宽度、连接长度与间隔层宽度比和地震危险性等级为主要变量，设计了72个EBF。对所有结构进行了弹性和弹塑性时程分析。结果表明，ASCE7-10中给出的位移放大系数提供了对楼层位移的非保守估计。另一方面，刚塑性机构提供了对杆件转动的保守估计。基于数值研究的结果，提出了一组新的沿结构高度变化的位移放大系数，并对刚塑性机构进行了修正。根据建议的修改，对EBF进行了重新设计，并使用弹塑性时程分析进行了分析。结果表明，建议的修改改进了位移放大系数和连杆转角计算程序。版权所有©2014 John Wiley&Sons，Ltd.
Inelastic deformation capacity of links is a factor that significantly influences design of steel eccentrically braced frames (EBFs). The link rotation angle is used to describe inelastic link deformation. The link rotation angle is generally calculated by making use of design story drifts that in turn are calculated by modifying the elastic displacements by a displacement amplification factor. This paper presents a numerical study undertaken to evaluate the displacement amplification factor given in ASCE7‐10 for EBFs and the rigid‐plastic mechanism used for calculating link rotation angles. A total of 72 EBFs were designed by considering the number of stories, the bay width, the link length to bay width ratio, and the seismic hazard level as the prime variables. All structures were analyzed using elastic and inelastic time history analyses. The results indicated that the displacement amplification factor given in ASCE7‐10 provides unconservative estimates of the story drifts. On the other hand, the rigid‐plastic mechanism provides conservative estimates of link rotations. Based on the results of the numerical study, a new set of displacement amplification factors that vary along the height of the structure and modifications to the rigid‐plastic mechanism were developed. In light of the proposed modifications, the EBFs were redesigned and analyzed using inelastic time history analysis. The results indicated that the proposed modifications provide improvements for the displacement amplification factor and link rotation angle calculation procedures. Copyright © 2014 John Wiley & Sons, Ltd.