北京财富中心二期写字楼铸钢节点有限元弹塑性分析

北京财富中心二期写字楼采用钢框架-钢板混凝土核心筒组合结构体系,位于26a层和41a层伸臂桁架与核心筒之间的连接节点采用铸钢节点形式.论文通过有限元弹塑性分析方法计算铸钢节点在不同地震组合作用下的节点应力和变形,并通过节点非线性时程计算方法分析铸钢节点的极限承载力.计算结果表明:本工程中的铸钢节点在整体结构小震和中震组合作用下基本处于弹性状态;在大震组合作用下,节点局部出现塑性应变,但塑性发展区域较小,因此仍保持较好延性;节点极限承载分析结果表明本工程中的铸钢节点设计方案满足承载力要求.     

大吨位铰接支腿门式起重机挠度的预测

门式起重机承受额定载荷时主梁跨中的下挠值是门式起重机整机试验的最重要检测指标。对于大吨位门式起重机整机实验时,实验砝码现场准备往往十分困难,甚至无法进行整机实验检验。针对铰接式门架结构,考虑支腿弯矩对主梁挠度的影响,推导出集中载荷在主梁跨中处作用时的挠曲线方程。通过分别测量三次小载荷在跨中处作用的主梁下挠值,求得门架结构主梁挠曲线方程系数,从而预测大吨位铰接式门式起重机额定载荷时主梁的下挠度。三次小载荷实验法为预测大吨位门架结构主梁挠度提供了实用有效的方法。     

A380登机桥新型稳定装置的开发

通过四轮行走的支腿方式探索、现有技术的各种支腿结构的分析,为A380登机桥设计了全新的凸轮稳定装置,其结构简单、自重轻,经机场的实际运行,证明可达到稳定A380登机桥的目的。     

核心单筒式高层悬挂结构中四面开洞核心筒体在水平力作用下的力学分析

用改进的连续化方法分析了核心单筒式高层悬挂结构中四面开洞核心简体在水平力作用下的力学性能，推导了计算核筒应力及位移与连梁剪力的简单公式。通过算例与ＳＡＰ８４结果比较表明，本文方法简单而省时。     

超高层结构应用液体黏滞阻尼器在中国的发展

液体黏滞阻尼器在高层和超高层建筑中起到抗震和抗风的结构保护作用,已经在国内外得到广泛认可。近十年来,在国内应设计院委托,前后计算分析了近20个高层、超高层建筑工程,其中7座已经被业主和超限审查通过,4个工程已经完成,3座已在施工或正在准备施工,还有几座在和业主讨论中,还有一半以上的建筑因各种原因阻尼器不能被采用,但在阻尼器的设计计算过程中,发现有很多创新点或启发,希望和设计者分享。在超高层结构发展应用过程中,美国的阻尼器设备公司在阻尼器开发方面也有很多发展,均做一简单介绍,供讨论参考。     

上海中心大厦伸臂桁架与巨柱和核心筒连接的静力性能试验研究

超高层框架-核心筒结构体系中,伸臂桁架连接着外围巨柱框架与内部核心筒,需传递巨大内力,其连接构造、传力机制等非常复杂。以上海中心大厦工程为背景,选取钢骨混凝土巨柱-伸臂桁架-环带桁架连接区域和伸臂桁架-核心筒连接区域进行了单调静力加载试验,并进行了有限元分析和简化模型计算分析。结果表明：伸臂桁架能够有效连接相邻构件并可靠传力,其破坏模式表现为伸臂桁架斜腹杆的受压屈曲以及上、下弦杆的弯曲变形,具有较好的延性;伸臂桁架与巨柱和核心筒连接的节点板虽然部分区域进入塑性,但塑性变形不明显,表明连接区域的承载力远高于杆件的承载力;有限元分析及简化模型分析结果与试验结果吻合良好;简化模型反映了伸臂桁架的非线性受力机理,可对其失效荷载进行准确预测,并可根据结构性能设计要求进行伸臂桁架分析和构件截面选择。     

上海中心大厦伸臂桁架与巨柱和核心筒连接的抗震性能试验研究

在上海中心大厦伸臂钢桁架与柱和核心筒连接单调静力试验的基础上,进行了该连接的抗震性能试验。试验设计了3种不同的反复加载路径,以考察普通循序渐增加载方式和不同损伤累积后再以普通循序渐增加载方式下试件滞回特性和耗能能力的差别。结果表明：在几种不同路径反复荷载作用下,试件最终破坏均发生在伸臂桁架斜腹杆和下弦杆端部,伸臂桁架与巨柱和核心筒连接的节点板塑性应力水平较低,滞回曲线形状饱满,延性较好,满足结构抗震设计要求;伸臂桁架在不同加载路径下的累积塑性耗能引起的塑性损伤对伸臂桁架的滞回性能退化有一定影响,但并不显著;单斜腹杆作为伸臂桁架耗能的主要构件,其累积轴力耗能占伸臂桁架总耗能的70%左右。     

Progressive collapse resisting capacity of tilted building structures

In this study, the progressive collapse resisting capacities of tilted buildings are evaluated on the basis of arbitrary column removal scenario. As analysis model structures both regular and tilted moment‐resisting frames, structures with outrigger trusses, and tubular/diagrid structures are designed, their progressive collapse resisting capacities are evaluated by nonlinear static and dynamic analyses. It turns out that the tilting of the structures requires increased steel tonnage due to the increased p‐delta effect. In addition in the tilted structures the plastic hinges are more widely distributed throughout the bays and stories when a column is removed from a side or a corner of the structures. With the analysis results, it is concluded that the tilted building structures, once they are properly designed to satisfy a given design code, may have at least an equivalent resisting capacity for progressive collapse caused by sudden loss of a column. Copyright © 2012 John Wiley & Sons, Ltd.     

Self‐centering viscoelastic diagonal brace for the outrigger of supertall buildings: Development and experiment investigation

This paper aims to improve the seismic performance of outriggers within supertall buildings and eliminate the defects of obvious degradation of stiffness, low energy dissipation capacity, and large residual deformation after the buckling of traditional diagonal members by presenting a new type of outrigger. The traditional profiled steel diagonal member is replaced with a self‐centering viscoelastic diagonal brace (SC‐VEDB) in the proposed outrigger, providing enhanced energy dissipation and self‐centering capacity. The new SC‐VEDB is composed of the inner and outer steel tubes, viscoelastic materials, and prestressed tendons. Energy dissipation capacity is produced by the shear deformation of viscoelastic materials, whereas prestressed tendons provide the self‐centering capacity. The working mechanism of SC‐VEDB is first theoretically analyzed. Following this, two specimens with a length of 2.2 m were designed, fabricated, and tested under low cyclic reversed loadings within different frequencies and pretension forces. The results confirm that the hysteretic curve of SC‐VEDB has a typical flag shape, which imparts the stable stiffness, good energy dissipation, and self‐centering capacities. The activation force of SC‐VEDB is mainly determined by the initial pretension force, and the post‐activation stiffness predominantly depends on the stiffness of the prestressed tendons. Moreover, SC‐VEDB has better repairability, and the initial hysteretic behavior of the component can be quickly recovered by replacing the damaged prestressed tendons. A refined finite element model for SC‐VEDB is established to predict its hysteretic behavior, and the numerical simulation corresponds well with the experimental results. The maximum relative error of the initial elastic stiffness and ultimate strength is approximately 4.6% and 1.3%, respectively, which verifies the accuracy of the SC‐VEDB numerical simulation method.     

巨型混合框架-核心筒结构的性能分析

巨型混合框架-核心筒结构是由巨型型钢混凝土框架、混凝土核心筒与伸臂桁架组成的一种具有多道抗震防线的超高层结构体系.为了有效地提高巨型混合框架-核心筒结构的抗侧刚度和内外筒之间的协同工作性能,可采取以下措施:增加巨型梁的刚度;增加伸臂桁架的刚度;增设巨型支撑.分析结果表明:设置跨越两个楼层的巨型梁或伸臂,或增设巨型支撑,...