带现浇楼板钢框架-剪力墙结构的拟动力试验研究

为研究楼板平面内刚度对整体结构抗震性能的影响,对一个3层2跨的钢框架-剪力墙结构进行了等效单自由度拟动力试验研究。着重分析了该钢框架-剪力墙结构的破坏机制、耗能性能及变形恢复能力,从而掌握该钢框架-剪力墙结构的抗震性能。结果表明,现浇混凝土楼板刚性可以保证结构的空间整体性和水平力的有效传递,该组合结构体系具有良好的抗震性能。最后通过对刚度比系数R的分析,得到该组合结构体系能保证剪力的有效传递,特别是在强震作用下,能够使不同抗侧力构件协同工作,剪力墙承担80%以上的地震剪力。     

底柱加强对高层混合结构地震能量反应的影响

近年来,能量分析方法在结构抗震设计中的应用问题受到国内外地震工程界的普遍关注,被认为是今后结构抗震设计理论的发展方向之一.以一钢框架-钢筋混凝土剪力墙混合结构为对象,通过逐渐增大框架底层柱截面,分析它们在不同类型地震波下的地震能量反应,结果表明,加强钢框架底层柱使结构总输入能基本不发生变化,结构滞回耗能在总输入能中的比例ν和底部剪力墙滞回耗能占结构总滞回耗能的比例μ均随结构刚度特征值λ的增大而减小,因此,加强钢框架底层柱能够提高外钢框架-内混凝土剪力墙结构体系的抗震能力,降低其在强震作用下的损伤程度.     

高层钢框架-混凝土核心筒混合结构振动台试验研究

为了研究高层钢框架-混凝土核心筒混合结构的整体抗震性能,本文设计了一个典型的比例为1/15的20层钢框架-混凝土核心筒混合结构的缩尺模型,在同济大学土木工程防灾国家重点实验室实施了模拟地震振动台试验。本文重点介绍试验中模型结构在各级水准地震作用下的动力特性、加速度和位移反应,描述了模型结构的破坏位置及过程,并根据相似理论得到了原型结构的地震反应。试验研究表明:原型结构基本能够满足我国现行规范"小震不坏、大震不倒"的抗震设防标准;核心筒发挥了主要抗侧力作用;结构在大震作用下有较好的延性;钢框架与核心筒的连接节点在结构设计时应给予重视。     

新型CS-MRF-BCSPSW体系性能的有限元分析

提出一种新型斜拉索-钢抗弯框架-梁连接钢板剪力墙(简称CS-MRF-BCSPSW)抗侧力体系。CS-MRF-BCSPSW体系综合了钢抗弯框架(MRFs)、钢板剪力墙(SPSWs)和斜拉索(CS)的各自优点,能有效地提升钢抗弯框架-梁连接钢板剪力墙(BCSPSWs)体系的抗侧力能力。CS-MRF-BCSPSW体系具有双重抗震防线和自复位能力,且BCSPSWs具有耗能能力。首先,阐述了CS-MRF-BCSPSW体系的组成及其ABAQUS有限元模型;接着,数值研究了CS-MRF-BCSPSW体系的抗侧力能力。具体地,数值研究了BCSPSWs的高厚比和宽高比、拉索截面面积、拉索倾角和拉索预应力对CSMRF-BCSPSW体系弹性刚度和抗侧力的影响和BCSPSWs的高厚比和宽高比和拉索预应力对CSMRF-BCSPSW体系滞回性能的影响。数值结果表明:CS-MRF-BCSPSW是一种新型的高性能抗震结构体系。     

钢框架-型钢混凝土剪力墙半刚性连接节点弯矩-转角模型及抗震性能研究进展

钢框架梁-型钢混凝土剪力墙新型混合结构是一种具有半刚性连接受力和优异的抗震性能等特点的新型混合结构,具有巨大的发展潜力,其卓越的性能吸引了越来越多的关注。在介绍国内外半刚性连接节点弯矩-转角模型及抗震性能研究进展的基础上,概述了目前各国学者对半刚性连接节点的研究成果和研究进展,提出了钢框架-型钢混凝土剪力墙半刚性连接节点在研究中存在的问题,并指出了钢框架-型钢混凝土剪力墙中半刚性连接节点的研究亟待开展。     

钢结构抗侧力体系抗震性能对比

常见的钢结构抗侧力体系包括抗弯钢框架、偏心支撑钢框架和钢板剪力墙结构,它们的耗能构件分别为框架梁、耗能梁段以及内填钢板。现行规范采用基于强度的设计方法,不能保证结构的整体破坏模式,无法对各抗侧力体系进行横向比较。采用近年来的性态设计方法,设计了3组10层抗弯框架、偏心支撑钢框架和钢板剪力墙模型,进行了静力弹塑性分析和动力弹塑性分析,对比了各抗侧力体系的承载能力、抗侧刚度、延性、层间侧移分布、破坏模式以及用钢量。对比结果表明:抗弯钢框架承载力和刚度最小,偏心支撑钢框架的延性最好,钢板剪力墙虽然承载力最高,但是延性却是最低。     

钢板剪力墙结构半刚性框架与内嵌墙板间的相互作用性能研究

为研究半刚性框架与钢板剪力墙结构内嵌墙板间的相互作用性能,完成了一榀1∶3比例单跨3层半刚性框架钢板剪力墙结构低周反复荷载试验研究。获得了结构的抗震性能和破坏模式,探究了框架梁、柱、墙板及梁柱节点的局部力学性能,分析了结构的破坏顺序和构件间的传力机理。研究结果表明:该结构具有良好的塑性变形能力和抗震性能,半刚性框架和墙板协同工作良好,结构安全储备较高。内嵌墙板的设置缓解了节点区自身的延性要求,框架承担95%以上的倾覆弯矩,水平荷载由双重抗侧力体系承担,内嵌墙板作为主要抗侧力构件承担约75%剪力。试件整体面内呈弯曲破坏,但是后期钢框架柱面外弯扭较大。通过有限元分析,研究了柱柔度系数、钢板高厚比和梁柱连接特性对钢板剪力墙结构性能的影响。框架梁柱连接刚度对结构体系承载能力的影响与柱的刚度和内嵌墙板的厚度有关。这种影响随着柱刚度增加和内嵌墙板厚度减小而增大。柱的柔度系数为2.5时,柱整体无明显的内凹变形,此时梁柱节点铰接连接更改为刚性连接时,试件承载能力增加小于10%。     

钢-混凝土组合剪力墙抗震研究与发展

剪力墙是高层建筑抗震的主要抗侧力体系,随着大型复杂高层建筑的快速发展,对剪力墙抗震性能的要求也越来越高,钢-混凝土组合剪力墙就是一种抗震性能好的剪力墙。国内外在钢-混凝土组合剪力墙抗震研究方面,从抗震性能到设计方法和工程应用都取得了较快的发展。本文介绍了国内外有关钢-混凝土组合剪力墙抗震研究的部分成果,同时介绍了笔者提出的钢-混凝土多重组合剪力墙及其抗震研究情况,包括工程应用情况。已有研究表明:钢-混凝土组合剪力墙特别是钢-混凝土多重组合剪力墙,具有良好的抗震屈服机制和多道抗震防线,抗震耗能能力强,工程应用价值较大。     

大跨度钢、木混合结构屋盖设计并基于实例分析对抗震性能的研究

为有效提高建筑中屋盖的抗震性能、节约建筑施工成本,深入研究大跨度钢、木混合结构屋盖的抗震性能。基于一个工程实例对该问题进行研究。分析从基本周期与抗侧刚度比、地震作用估算、承载力设置、抗震变形验算、连接与基础设计五个测试参数展开,在此基础上确定预应力拉索的地震响应及张拉控制应力。设计的混合屋盖是使用4道X形布置的屋面预应力主索与外柱斜拉索结构,这样是确保屋盖结构在地震下能够有效工作,根据该结构结合一工程实例展开大跨度钢、木混合结构屋盖抗震性能测试。实验结果表明,大跨度钢、木混合结构屋盖相对单一结构屋盖而言,抗震性能更强;同时实例分析表明,在多向地震输入下大跨度钢、木混合结构屋盖的各个构件中,内柱是抗震性能较弱的部位。     

钢框架-型钢混凝土剪力墙新型混合结构二阶非弹性地震反应分析

钢-混凝土混合结构作为高层建筑结构体系中的重要组成部分已经得到广泛的实践与应用,其中钢框架-型钢混凝土剪力墙混合结构是一种新型的混合结构体系。首先对国内外的钢-混凝土混合结构工程做了简要介绍,然后回顾了国内外关于钢-混凝土混合结构的地震反应分析理论和试验的研究现状与动态,并提出了当前钢-混凝土混合结构研究中存在的一些问题。     

横向钢梁空间约束作用对钢框架-混凝土核心筒结构弹塑性地震反应的影响

本文基于文献[5]建立的钢框架-混凝土核心筒混合结构弹塑性地震反应的拟三维分析模型,进一步考虑钢框架和核心筒之间横向梁的空间扭转作用,讨论了横向梁空间约束作用对钢框架-混凝土核心筒混合结构弹塑性地震反应的影响。算例分析表明:进一步考虑横向梁的空间扭转作用后所得的楼层位移和层间位移角比只考虑竖向作用所得的值偏大,可见,采用考虑横向梁空间竖向和扭转约束作用的拟三维分析方法更合理。     

屈曲约束支撑钢框架结构影响因素的静力弹塑性分析

为检验抗侧刚度比和支撑布置方式等因素对具有不同总层数的屈曲约束支撑钢框架的抗震性能影响,借助SAP2000软件,探讨6层、12层、18层屈曲约束支撑钢框架结构在抗侧刚度比分别为1、2、3、4、5共五种工况及倒V型和单斜向两种支撑布置方式下的抗震性能。结果表明,屈曲约束支撑钢框架结构基底剪力-顶点位移曲线呈典型的双线性特征;随抗侧刚度比的增大,结构的层间位移角总体上呈降低趋势,基底剪力及支撑轴力增大,顶点水平位移变小,框架所分担的剪力降低;倒V型布置支撑较单斜向布置具有略大的基底剪力、谱加速度,较小的顶点位移、层位移、层间剪力和框架剪力分担率。分析表明,总体上来看,倒V型布置较单斜向布置时支撑框架结构具有略优的抗震性能;抗侧刚度比较支撑布置方式对支撑框架结构抗震性能的影响更为显著。     

Shake-table testing of a self-centering precast reinforced concrete frame with shear walls

The seismic performance of a self-centering precast reinforced concrete (RC) frame with shear walls was investigated in this paper. The lateral force resistance was provided by self-centering precast RC shear walls (SPCW), which utilize a combination of unbonded prestressed post-tensioned (PT) tendons and mild steel reinforcing bars for flexural resistance across base joints. The structures concentrated deformations at the bottom joints and the unbonded PT tendons provided the self-centering restoring force. A 1/3-scale model of a five-story self-centering RC frame with shear walls was designed and tested on a shake-table under a series of bi-directional earthquake excitations with increasing intensity. The acceleration response, roof displacement, inter-story drifts, residual drifts, shear force ratios, hysteresis curves, and local behaviour of the test specimen were analysed and evaluated. The results demonstrated that seismic performance of the test specimen was satisfactory in the plane of the shear wall; however, the structure sustained inter-story drift levels up to 2.45%. Negligible residual drifts were recorded after all applied earthquake excitations. Based on the shake-table test results, it is feasible to apply and popularize a self-centering precast RC frame with shear walls as a structural system in seismic regions.     

型钢混凝土梁柱框支剪力墙结构抗震性能试验研究

框支剪力墙结构在实际工程中经常被采用,震害表明钢筋混凝土框支剪力墙结构抗震性能较差,本文提出型钢混凝土梁柱框支剪力墙结构对此加以改进。作者进行了4个1/4缩尺模型在竖向荷载和单调及低周反复水平荷载作用下的对比试验,其中3个试件采用型钢混凝土转换梁、型钢混凝土框支柱,1个试件采用钢筋混凝土转换梁、钢筋混凝土框支柱。我们分析其承载力、刚度、变形、延性和破坏形态等。试验结果表明,型钢混凝土梁柱框支剪力墙结构承载力高、延性好、滞回曲线丰满,变形能力和耗能能力较强。     

Shaking table model test on Shanghai World Financial Center Tower

The height of 101‐storey Shanghai World Financial Center Tower is 492m above ground making it possible the tallest building in the world when completed. Three parallel structural systems including mega‐frame structure, reinforced concrete and braced steel services core and outrigger trusses, are combined to resist vertical and lateral loads. The building could be classified as a vertically irregular structure due to a number of stiffened and transfer stories in the building. Complexities related to structural system layout are mainly exhibited in the design of services core, mega‐diagonals and outrigger trusses. According to Chinese Code, the height 190 m of the building clearly exceeds the stipulated maximum height of for a composite frame/reinforced concrete core building. The aspect ratio of height to width also exceeds the stipulated limit of 7 for seismic design intensity 7. A 1/50 scaled model is made and tested on shaking table under a series of one and two‐dimensional base excitations with gradually increasing acceleration amplitudes. This paper presents the dynamic characteristics, the seismic responses and the failure mechanism of the structure. The test results demonstrate that the structural system is a good solution to withstand earthquakes. The inter‐storey drift and the overall behaviour meet the requirements of Chinese Design Code. Furthermore, weak positions under seldom‐occurred earthquakes of seismic design intensity 8 are found based on the visible damages on the testing model, and some corresponding suggestions are proposed for the engineering design of the structure under extremely strong earthquake. Copyright © 2006 John Wiley & Sons, Ltd.     

Study of the seismic response of a recycled aggregate concrete frame structure

Based on six-degree-of-freedom three-dimensional shaking table tests, the seismic response of a recycled aggregate concrete （RAC） frame was obtained. The analysis results indicate that the maximum story shear force and overturning moment reduce proportionally along the height of the model under the same earthquake wave. The story shear force, base shear coefficient and overturning moment of the structure increase progressively as the acceleration amplitude increases. The base shear coefficient is primarily controlled by the peak ground acceleration （PGA）. The relationships between the PGA and the shear coefficient as well as between the PGA and the dynamic amplification factor are obtained by mathematical fitting. The dynamic amplification factor decreases rapidly at the elastic-plastic stage, but decreases slowly with the development of the elastic-plasticity stage. The results show that the RAC frame structure has reasonable deformability when compared with natural aggregate concrete frame structures. The maximum inter-story drift ratios of the RAC frame model under frequent and rare intensity 8 test phases are 1/266 and 1/29, respectively, which are larger than the allowable value of 1/500 and 1/50 according to Chinese seismic design requirements. Nevertheless, the RAC frame structure does not collapse under base excitations with PGAs from 0.066 g up to 1.170 g.     

型钢混凝土低矮剪力墙抗震性能试验研究

剪力墙构件是现代高层建筑结构中的主要抗侧向力构件.为了对比型钢桁架混凝土组合低矮剪力墙与型钢框架混凝土组合低矮剪力墙以及普通钢筋混凝土低矮剪力墙在地震作用下的抗震性能,本文进行了四榀1/4缩尺模型的低矮混凝土剪力墙在单调和低周反复荷载作用下的对比试验,其中单调加载试验包括一榀内置型钢桁架的型钢混凝土组合低矮剪力墙,反复加载试验包括一榀普通钢筋混凝土低矮剪力墙、一榀内置型钢框架的型钢混凝土低矮剪力墙和一榀内置型钢桁架的型钢混凝土低矮剪力墙,给出了各试件的刚度、承载力、变形、延性和破坏形态等试验结果,并对其进行分析.试验结果表明,在这三种墙体中,型钢桁架混凝土组合低矮剪力墙的承载力、变形能力、耗能能力较其他类型剪力墙好,并为型钢桁架混凝土组合低矮剪力墙在实际中的应用提供了试验依据.     

A study on the seismic performance of steel‐reinforced concrete frame‐concrete core wall high‐rise mixed structure by large‐scale shaking table tests and numerical simulations

This paper reports a study for the seismic performance of one large‐scaled (1/15) model of 30‐story steel‐reinforced concrete frame‐concrete core wall mixed structure. The study was implemented by both shaking table tests, in which the similarity ratio for lateral and gravitational accelerations was kept to 1:1, and numerical nonlinear dynamic analysis. The test observations presented herein include story displacement, interstory drift, natural vibration periods, and final failure mode. The numerical analysis was performed to simulate the shaking table test procedure, and the numerically obtained responses were verified by the test results. On the basis of the numerical results, the progressions of structural stiffness, base shear, and overturning moment were investigated, and the distributions of base shear and overturning moment between frame and core wall were also discussed. The test demonstrates the seismic performance of the steel‐reinforced concrete frame‐core wall mixed structure and reveals the potential overturning failure mode for high rise structures. The nonlinear analysis results indicate that the peripheral frames could take more shear forces after core wall damaged under severe earthquakes. Copyright © 2013 John Wiley & Sons, Ltd.     

基于实例分析的绿色钢结构抗震与环保性能研究

为优化绿色钢结构建筑的安全性能与环保性能,基于一40层框架-支撑钢结构建筑实例进行抗震性能与环保性能分析。根据实际建筑参数构建该绿色钢结构建筑剖面图,基于时程分析法记录不同地震波作用下建筑水平位移随时间变化情况,基于Pushover分析法分析方钢管混凝土组合异形柱在罕见地震中的基底剪力和弹塑性变形,基于对比实验方法验证其环保优越性,并得出以下结论：建筑的方钢管混凝土组合异形柱符合国家抗震性能要求,整体建筑的抗震性能随楼层的增加而减弱;与钢筋混凝土结构、砖混结构相比,钢结构能有效节约施工水电用量、降低施工噪声,是一种抗震性强、环保性能优的绿色建筑形式。