偏心支撑框架的设计方法概述

参考美国抗震规范AISC 341—05和GB 50010—2010建筑抗震设计规范,对偏心支撑框架的设计方法进行探讨,重点介绍了消能梁段、加劲肋的布置、柱、支撑以及消能梁段以外梁段的设计,预期可增强设计人员对该种结构体系设计方法的了解,为同类结构体系的设计提供参考。     

低屈服点钢偏心支撑框架抗震性能研究

将偏心支撑框架中的消能梁段腹板替换为低屈服点钢材,形成低屈服点钢偏心支撑框架.为实现震后修复的功能,消能梁段与主体结构通过高强螺栓及端板进行连接.建立了单层支撑框架和高宽比为2的高层支撑框架,对比分析了普通钢偏心支撑框架与低屈服点钢偏心支撑框架的抗震性能.有限元分析结果表明,单层支撑框架在相同变形状态下,低屈服点钢偏心...     

偏心支撑钢框架的设计

简述了偏心支撑钢框架结构的工作原理及特点,介绍了偏心支撑钢框架的设计计算方法,其中重点介绍了各杆件的内力计算：耗能梁段设计、非耗能梁段设计、支撑设计和框架柱设计,为工程设计人员提供了指导。     

一种新型扩孔螺栓连接型消能梁段及其力学性能

罕遇地震下偏心支撑框架结构需合理有效地增大消能梁段的延性和耗能能力,并减小消能梁段的损伤,以使该种结构能更好地适应当前的抗震要求。基于剪切型消能梁段的力学特性和扩孔型螺栓连接的受剪滑移能力,提出一种扩孔螺栓连接型消能梁段。采用校正的有限元方法对扩孔型螺栓连接和扩孔螺栓连接型消能梁段进行详细分析,以明确相应试件的力学性能。研究结果表明,扩孔螺栓连接型消能梁段具有高延性和强耗能等特点,能有效提高偏心支撑框架结构的抗震性能和震后功能恢复能力,并为偏心支撑框架结构的抗震设计提供新的思路和方法。     

Y型偏心支撑钢框架的受力性能研究

Y型偏心支撑钢框架是最近发展起来的一种新型抗侧力结构体系,具有很好的抗震性能。可以通过改变耗能梁段的截面尺寸和支撑的布置形式来优化结构的抗震性能。本文基于我国现行《抗震规范》建立三个系列的一榀Y型偏心支撑钢框架平面模型,并运用有限元分析软件sap2000对结构进行pushover分析计算,研究了Y型偏心支撑钢框架的耗能梁段长度、腹板高厚比和耗能支撑的布置形式等参数对Y型偏心支撑钢框架结构抗震性能的影响,提出了相应的抗震设计建议。     

消能偏心支撑结构中粘弹性阻尼器的参数优化

通过对粘弹性阻尼器的性能与特点以及消能支撑计算模型的分析,建立了粘弹性阻尼器参数优化的计算模型:以粘弹性阻尼材料的储存剪切模量为设计变量;以各层最大层间位移的最大值的控制率和各层耗能梁段最大梁端弯矩的最大值的控制率为约束条件;在考虑结构在罕遇地震下的地震反应以及结构的经济效益的目标下,建立了优化设计的目标函数.文中以设置粘弹性阻尼偏心支撑的五层平面钢框架为例,使用ANSYS软件中的优化设计模块,通过APDL语言编制优化设计程序,建立了参数优化模型,并对该问题进行了优化设计分析;并对偏心支撑结构和消能偏心支撑结构进行了罕遇地震下的时程分析.计算结果表明:ANSYS软件中的优化设计方法稳定可行;消能偏心支撑可以有效地降低结构的地震反应,对顶层位移的最大减小量可达44.96%;耗能梁段梁端弯矩的最大耗能效果达到37.4%,这样可以延缓耗能梁段的屈服时间,从而可以有效地保证结构的整体稳定.     

偏心支撑框架结构整体刚度方程的建立和求解

对偏心支撑框架消能梁段在不同屈服状态下耗能的计算方法进行了分析，对空间杆单元刚度方程的建立进行了理论推导，并对结构整体刚度方程的求解步骤进行了详细阐述，指出该计算方法的应用性。     

北京泰康大厦钢结构设计

北京泰康大厦为高烈度地震区的超高层建筑。综合考虑建筑形体、功能与布置以及结构抗震要求,主体结构采用双重抗侧力体系钢框架-支撑筒体结构。塔楼外围为钢框架结构,中间核心筒采用带消能梁段的偏心支撑筒体,整体结构具有质量轻、地震作用小、抗震性能优越等优点。整体结构分析表明,结构各项整体指标均满足规范要求。对带消能梁段的偏心支撑筒体、外框斜柱、角部大悬挑楼盖结构以及地下室矩形钢管混凝土柱剪力墙筒体等关键结构构件进行了深入分析,提出了合理的应对措施和设计构造。     

偏心支撑结构体系的研究进展及展望

偏心支撑结构作为一种消能减震结构体系,近几十年来得到了广泛的研究和应用,取得了许多具有理论价值和工程意义的成果,并在新建建筑、桥梁和建筑抗震加固等领域中得到了应用。随着国家对建筑结构的抗震性能和震后功能快速恢复能力提出了更高的要求,偏心支撑结构在实际工程中将会有更加广泛的应用。为此,从剪切型消能梁段和偏心支撑结构体系的角度出发,详细阐述了剪切型消能梁段的力学性能及其影响因素,以及偏心支撑结构的抗震性能、破坏模式和震后修复方法等。最后,提出一种新型组合楼板和扩孔螺栓连接型消能梁段并应用于偏心支撑结构体系中,由此进一步提高偏心支撑结构的抗震性能和震后功能快速恢复能力,使该种结构体系能更好地适应当前要求。     

偏心支撑钢框架基于性能的塑性设计方法研究

罕遇地震下采用弹性分析所设计的偏心支撑框架发生较大的非弹性变形时,可能无法满足预期的破坏模式和抗震性能。通过预先确定结构在非弹性变形下的目标位移和屈服机理,结合《建筑抗震设计规范》(GB50010—2010)并考虑消能梁段的耗能折减系数,提出了偏心支撑框架基于性能的塑性设计方法。该方法还采用能量平衡原理和一种侧向力分布方式得到结构的基底剪力和各楼层的剪力,并根据塑性设计法合理设计所有构件。设计某12层偏心支撑钢框架,采用动力弹塑性时程分析法验正所提出方法的正确性。算例结果表明:该方法可用于设计偏心支撑钢框架结构,且无需进行复杂的计算和迭代,就能使结构满足多遇及罕遇地震下的预定功能。     

Seismic performance of Y‐type eccentrically braced frames combined with high‐strength steel based on performance‐based seismic design

In the Y‐type eccentrically braced frame structures, the links as fuses are generally located outside the beams; the links can be easily repairable or replaceable after earthquake without obvious damage in the slab and beam. The non‐dissipative member (beams, braces, and columns) in the Y‐type eccentrically braced frames are overestimated designed to ensure adequate plastic deformation of links with dissipating sufficient energy. However, the traditionally code design not only wastes steel but also limits the application of eccentrically braced frames. In this paper, Y‐type eccentrically braced steel frames with high‐strength steel is proposed; links and braces are fabricated with Q345 steel (the nominal yield stress is 345 MPa); the beams and columns are fabricated with high‐strength steel. The usage of high‐strength steel effectively decreases the cross sections of structural members as well as reduces the construction cost. The performance‐based seismic design of eccentrically braced frames was proposed to achieve the ideal failure mode and the same objective. Based on this method, four groups Y‐type eccentrically braced frames of 5‐story, 10‐story, 15‐story, and 20‐story models with ideal failure modes were designed, and each group includes Y‐type eccentrically braced frames with ordinary steel and Y‐type eccentrically braced frames with high‐strength steel. Nonlinear pushover and nonlinear dynamic analyses were performed on all prototypes, and the near‐fault and far‐fault ground motions are considered. The bearing capacity, lateral stiffness, story drift, link rotations, and failure modes were compared. The results indicated that Y‐type eccentrically braced frames with high‐strength steel have a similar bearing capacity to ordinary steel; however, the lateral stiffness of Y‐type eccentrically braced frames with high‐strength steel is smaller. Similar failure modes and story drift distribution of the prototype structures designed using the performance‐based seismic design method are performed under rare earthquake conditions.     

高层钢结构支撑方案抗震性能对比分析

高层钢结构中框架—支撑结构是一种常用的结构形式,文中介绍了支撑结构体系的发展情况.以某实际工程为例,说明了普通钢支撑和屈曲约束支撑两种不同支撑对结构弹性性能的影响,通过静力弹塑性推覆分析对比研究了两种方案的弹塑性性能,并对屈曲约束支撑采用偏心布置形式对框架梁的影响进行了探讨.     

Seismic behaviour of eccentrically braced frames

In the past, the analysis of the seismic behaviour of eccentrically braced frames designed in fulfilment of capacity design principles has highlighted the significant role of the link overstrength factor. The link overstrength factor is, however, unable to explain many seismic responses because it is defined on the basis of the sole elastic behaviour of structures. To achieve thorough comprehension of the seismic behaviour of eccentrically braced systems, a new parameter, called damage distribution capacity factor, is defined here. The proposed parameter is calculated on the basis of the inelastic structural behaviour and is intended to evaluate the effect of premature yielding of links on the ability of structures to develop significant inelastic behaviour of all links prior to link failure. The paper discusses the distribution of the damage distribution capacity factor in eccentrically braced structures designed in accordance with capacity design principles and the influence of this parameter on the seismic response of structures. Finally, an analytical relation is defined between overstrength factor of links, damage distribution capacity factor and plastic rotation of links to obtain quantitative evaluation of the structural damage of eccentrically braced structures upon first failure of links.     

单斜杆型偏心支撑钢框架的地震反应分析

偏心支撑结构弹性阶段刚度大,塑性阶段耗能能力强,是适用于高烈度地震区的一种有效的抗侧力结构体系。采用梁单元与壳单元相结合的非线性有限元模型,对单斜杆型偏心支撑钢框架进行弹塑性时程分析,研究耗能梁段的长度、腹板高厚比和加劲肋间距的变化对单斜杆型偏心支撑钢框架结构抗震性能的影响,提出了相应的抗震设计建议。     

偏心支撑钢框架能力设计方法研究

结合国内外偏心支撑钢框架结构的最新研究成果以及相关设计规范的规定,对偏心支撑钢框架结构的性能进行分析,介绍偏心支撑钢框架结构的能力设计方法,对我国规范相对落后的部分进行补充,为工程设计提供一些参考。着重阐述耗能梁段,耗能梁段外的梁、支撑、柱和耗能梁-柱节点的设计,同时总结了偏心支撑钢框架结构设计中应注意的问题。     

设置粘弹性阻尼器的偏心支撑结构性能研究

指出偏心支撑结构的不足,提出了在偏心支撑结构的支撑上设置粘弹性阻尼器(称之为消能偏心支撑)来弥补其不足,分析了消能偏心支撑结构的消能减震原理和单自由度下的地震响应,接着以实例对比了偏心支撑结构与消能偏心支撑结构的位移、内力等。分析结果表明:消能偏心支撑具有良好的抗震性能,起到了"双保险"的作用。     

Recent research on eccentrically braced frames

Recent research developments on eccentrically braced steel frames for seismic design are reviewed. The emphasis is placed on the design of links, which are short sections of beams between columns and braces, and similar elements at eccentric joints. The review includes some highlights of the latest experiments with one-third scale models employing different eccentric bracing schemes, an updated classification of links, and special design requirements for different types of links. Some results are given on recent cyclic tests of full-size links.     

某偏心支撑框架结构设计

偏心支撑框架在弹性阶段的刚度接近中心支撑框架,弹塑性阶段的延性和耗能能力接近延性框架,是一种新型的高层钢结构抗震体系。以咸阳丽彩.天玺广场商住楼工程为例,详细介绍偏心支撑框架的耗能梁段、非耗能梁段、支撑和柱的设计以及构造措施,有助于工程设计人员更好地了解该结构体系设计过程,可为类似工程设计提供参考。     

Effects of the frame geometry on the weight and inelastic behaviour of eccentrically braced chevron steel frames

Many experimental and analytical studies about eccentrically braced frames (EBFs) have been carried out since the late 1970s. However, parametric studies about the effects of the frame geometry on the weight and global inelastic behaviour are still quite limited. Such kind of parametric studies require many number of designed EBFs for the purpose of generalization, in fact, optimization of design is also necessary for the conservatism of results. Therefore, a computer program based on an iterative optimization procedure is coded for the design of eccentrically braced chevron frames and the algorithm is given. In this research, 420 EBFs with shear yielding links, 105 EBFs with intermediate links, and 105 EBFs with flexural yielding links are designed. Inelastic dynamic analyses of each of these frames are performed under 20 SAC ground motions with DRAIN-2DX whose input files are prepared automatically by another program coded. Each earthquake record for each frame is scaled by the program by modifying the DRAIN input files in an automated manner until one of the links reaches the code-based limit rotation angle, and the resultant scale factors are utilized for comparison of the frames’ inelastic behaviours. The equation for plastic link rotation of EBFs given in AISC-2005, which does not consider the vertical displacements of the column ends is modified to include these displacements and used in the inelastic analyses. Effects of the geometry selection on the frames’ seismic behaviours and weights are given. Push-over analyses of some of the designed frames are also performed with DRAIN-2DX in order to compare their displacement ductilities.