连柱框架结构基于性能的塑性设计与评估(英文)

Performance-Based Plastic Design and Evaluation of Linked Column Frames

抗弯钢框架结构(MRF)是目前研究最广泛、最流行的抗震系统,具有建筑灵活度高和施工效率高等优点。然而,这种结构常常缺乏足够的侧向刚度来限制结构的位移角,会导致在强震下结构和非结构构件产生严重的破坏。相反,偏心支撑钢框架结构(EBF)却有很大的侧向刚度来限制结构的位移角和有专属的抗震耗能构件。但是,支撑结构并不为建筑师所广泛接纳。为了结合抗弯钢框架结构和偏心支撑钢框架结构的优点,于2007年首次提出一种新型的抗震系统——连柱框架结构(LCF)。这种双抗震系统有相似于偏心支撑钢框架结构的窄连梁框架作为主要的抗震系统,而抗弯钢框架结构则作为次要的抗震系统。连梁作为结构保险丝可以在中震到大震中消耗地震能量,而且在震后很容易就可以被替代和修复。另一方面,抗弯钢框架结构可以提供附加的侧向抵抗力来防止结构在大震下倒塌。采用2008年提出的基于性能的塑性设计方法(PBPD)对建筑原型位于美国强震地区——加州洛杉矶的连柱框架结构进行设计。最后,使用先进的基于性能的评估步骤对原型结构的抗震性能进行了研究。研究结果表明,连柱框架结构(LCF)是一种具有良好抗震性能的结构。

Steel moment resisting frames （MRFs） are one of the most well researched and prevalent seismic force resisting systems. They provide many advantages which include architectural flexibility and efficient construction scheme. However, such a system lacks of lateral stiffness to limit structural drift which leads to significant structural and non- structural damages during strong earthquake shakings. Steel eccentrically braced frames （EBFs）, on the other hand, have high stiffness to limit structural drift and designated structural links to dissipate earthquake energy. However, added braces are not well received by architects. To combine the advantages of steel MRFs and EBFs,a novel seismic force resisting system,linked column frames （LCFs） ,has been proposed in 2007. The resulting dual system has narrow link bays similar to EBFs as the primary seismic force resisting system and MRFs as the secondary seismic force resisting system. The links in link bays act as structural fuses to dissipate earthauake energy during moderate to strong earthquake shakings and are designed to be efficiently replaceable after earthquakes, while MRFs provide additional lateral resistance to prevent buildings from collapse during strong earthquake shakings. The performance-based plastic design （PBPD） methodology originally developed was adopted in this study to design LCFs in 2008. A prototype building located in Los Angeles,California,was designed using the proposed LCF system with the PBPD methodology. The seismic performance of the prototype building under the design based earthquake shaking intensities was analysed using the state-of-the-art performance-based assessment procedure. The result demonstrates that the proposed LCF is a robust seismic force resisting system.