低屈服钢造耐震间柱构架之抗震行为

传统抗弯构架加入耐震间柱后可使刚度、强度与韧性获得提升,因此可设计为新建筑的抗震系统或既有建筑的补强.本文探讨一种中间段以低屈服强度钢材为腹板,高强度钢为翼板,上下段皆以高强度钢制成之三段式剪力屈服型耐震间柱.本文并使用非线性分析程序探讨耐震间柱的受震反应,并与一般抗弯构架作比较.由分析中可发现,楼层位移角及侧向位移均有显著的减小,其塑铰也由梁端成功地转移至间柱上.而耐震间柱的确也肩负起消能的责任,使得在地震发生时能消释构架中大部分的迟滞能量.     

极低屈服点软钢阻尼器恢复力模型的研究

本文通过试验和理论分析探讨极低屈服点软钢阻尼器的恢复力特性。随着塑性变形的发展将恢复力模型中的骨架曲线进行平移,其卸载曲线用Ramberg—Osgood函数来描述,由此得到的恢复力模型定义为骨架平移模型,将其应用于描述极低屈服点软钢阻尼器的恢复力特性、为了验证该馍型的有效性并确定合理的参数,对安装极低屈服点软钢阻尼器的3层钢框架结构进行了拟动力试验．同时用该骨架平移模型模拟极低屈服点软钢阻尼器的恢复力特性进行了大量的弹塑性地震反应分析,通过取用不同平移系数时的数值计算结果与拟动力试验结果的比较,发现平移系数为0．6左右时,该模型具有较高的精度。     

波纹钢管铅阻尼器耗能性能分析研究

提出一种波纹钢管铅阻尼器,介绍了其构造、工作机理、布置形式及特点,采用ABAQUS软件,建立钢管阻尼器、波纹钢管阻尼器和波纹钢管铅阻尼器有限元模型,对其应力分布,传力路径和滞回性能进行模拟分析。结果表明:波纹钢管铅阻尼器耗能减震机理明确,工作性能和耗能性能稳定,滞回曲线饱满以及耗能能力强,具有良好的变形和延性,极限变形大;波纹钢管铅阻尼器通过在波纹钢管内设置铅芯使初始刚度、承载能力和耗能能力得到大幅度提高,既有效保持了波纹钢管的变形能力,又避免波纹钢管发生局部屈曲,使波纹钢管耗能能力得到充分发挥。波纹钢管铅阻尼器在1mm小位移下就可以进入耗能,而且很快进入稳定耗能状态,等效阻尼比稳定在0.3~0.4之间。     

Hysteretic behaviour of bracing‐type pure aluminium shear panels by experimental tests

This paper deals with experimental tests aimed at assessing the structural performance of pure aluminium shear panels to be employed as passive energy dissipation devices with a bracing type configuration. The AW1050 A H24 is adopted as the basic material. It is an aluminium alloy with a negligible content of impurity, allowing it to be considered as a pure aluminium. In this paper, the results of four full‐scale 5thinspacemm thick multi‐stiffened square‐shaped specimens tested under cyclic diagonal loads and characterized by different slenderness ratios are presented. In order to determine the main resisting mechanisms for different shear strain demands, a careful examination of the experimental evidences is provided. Then, the global performance of tested shear panels is evaluated by the comparison of the obtained hysteretic responses, evidencing the effect of the plate slenderness on the energy dissipation capacity. Finally, a suitable analytical model, which could be useful to implement global dynamic non‐linear analysis, is set up in order to interpret the behaviour of shear panels for which the development of premature buckling phenomena is completely inhibited. Copyright © 2010 John Wiley & Sons, Ltd.     

Pure aluminium shear panels as dissipative devices in moment‐resisting steel frames

The use of energy dissipation systems for the seismic control of steel structures represents a valid alternative to conventional seismic design methods. The seismic devices currently employed are mostly based on the metallic yielding technology due to the large feasibility and efficiency they can provide. Within this context, in the current paper an innovative solution based on the adoption of low‐yield‐strength pure aluminium shear panels (SPs) for seismic protection of steel moment‐resisting frames is proposed and investigated. In order to prove the effectiveness of the system, a wide numerical study based on both static and dynamic non‐linear analyses has been carried out, considering a number of different frame‐to‐shear panel combinations, aiming at assessing the effect of the main influential parameters on the seismic response of the structure. The obtained results show that the contribution provided by aluminium SPs is rather significant, allowing a remarkable improvement of the seismic performance of the structure in terms of stiffness, strength and ductility, with the possibility to strongly limit the damage occurring in the members of moment‐resisting frames. In particular, it is clearly emphasized that the stiffening effect provided by SPs allows a more rational design procedure to be adopted, since the serviceability limit state check does not lead to unavoidable and uneconomical increase of the size of main structural members. Copyright © 2007 John Wiley & Sons, Ltd.     

Cyclic shear behaviour of steel box girders: experiment and analysis

An experimental investigation of the cyclic shear behaviour of steel box girders was conducted on one‐quarter scale models, comprising of two specimens with longitudinally unstiffened webs and one specimen with longitudinally stiffened webs. All the specimens exhibited ductile behaviour. The tests evidenced significant increases in the shear strength and energy dissipation capacity regarding the use of thicker webs and the provision of longitudinal web stiffeners. The web stiffeners also enhanced the stable hysteresis behaviour without substantial degradation in the energy dissipation due to pinching. The test results are compared with the shear behaviour simulated by inelastic large deformation analysis incorporated with a sophisticated constitutive model. The hysteresis behaviour, peak cyclic shear stresses, energy dissipation, and deformation shapes of the three specimens are satisfactorily predicted by the analysis. It is verified that the presented analytical method can be used precisely for further investigations of box girders in shear. Copyright © 2002 John Wiley & Sons, Ltd.     

配置自复位耗能跨低多层钢框架体系的能量系数

利用超弹性SMA螺栓梁柱节点的耗能能力和自复位特性,将其引入到耗能跨而构建"自复位耗能跨",基于既有的节点试验研究结果对结构体系的滞回性能进行了探讨。在此基础上,以具有旗形滞回特征的单自由度体系为工具,对配置自复位耗能跨低多层钢框架体系的能量系数进行推导。能量系数可以合理量化具有旗形滞回规则结构的峰值响应需求,能量系数越低,表明地震动下结构的峰值响应越低。为了阐明滞回参数对能量系数的影响,对具有不同滞回参数组合可代表低多层结构的等效SDOF体系进行了非线性动力分析,参数组合包括周期、屈服后刚度比、延性系数及能量比。同时对能量系数的离散性也进行了分析。结果表明:能量系数及能量系数的离散性受结构周期、屈服后刚度比及延性系数影响较大,受能量比的影响较小。     

Seismic behaviour of steel plate shear wall systems with staggered web configurations

Unstiffened steel plate shear walls (SPSWs) are used as lateral load‐resisting systems in building structures. The energy dissipation mechanism of SPSWs consists of the tension yielding of web plates and the formation of plastic hinges at the ends of horizontal boundary elements. However, vertical boundary elements (VBEs) of high‐rise SPSWs may experience high axial forces under lateral loading. This study explores the effectiveness of staggering of web plates on the reduction of VBE forces and drift response of SPSWs during an earthquake event. An analytical study has been conducted to determine the base shear reduction factor so as to match the overstrength of staggered systems with conventional SPSWs. A design methodology has been proposed for staggered SPSWs. Six‐, 9‐, and 20‐storey staggered and conventional SPSWs with varying aspect ratios are considered in this study to compare their seismic response. These study frames are modelled and analysed in OpenSEES platform. Nonlinear static and dynamic analyses are performed to compare the drift response, hinge mechanisms, and steel tonnage. Staggered SPSWs showed uniform drift distribution and reduction in interstorey drift and axial force demand on the VBEs.     

低屈服点钢研究进展与力学性能数据分析

为对低屈服点钢进行进一步的研究,同时促进其在工程中的应用,全面综述了国内外学者对低屈服点钢材料的研究成果,主要包括单调拉伸性能、循环加载性能以及低屈服点钢材料的应用。并将文献中的力学性能参数进行统计,采用K-S检验法对屈服强度与抗拉强度进行检验。结果表明:低屈服点钢具有良好的延性与滞回性能,力学性能参数基本满足规范要求;3种钢材的伸长率均随厚度增大而增大;低屈服点钢屈服强度符合正态分布,抗拉强度则不符合正态分布;实际工程中对低屈服点钢耗能构件的应用仍相对较少,还需进一步对其进行深入研究,以提高其应用比例。     

内藏钢桁架混凝土组合低剪力墙抗震性能试验研究

进行了3个1/3缩尺的低剪力墙的抗震性能试验研究,包括1个普通混凝土低剪力墙、1个内藏钢框架混凝土组合低剪力墙和1个内藏钢桁架混凝土组合低剪力墙。在试验研究基础上,对比分析了各剪力墙的刚度及其衰减过程、承载力、延性、滞回特性、钢筋应变、耗能能力及破坏特征。试验表明:内藏钢框架和内藏钢桁架混凝土组合低剪力墙的抗震性能比普通混凝土低剪力墙明显提高。     

基础隔震结构的耗能分析

采用Bouc-wen模型,利用状态空间迭代法,对基础隔震结构进行了多质点的弹塑性时程分析,并根据此结果,利用能量方程,求得隔震结构的各项能量,绘制了各能量项时程曲线。以一实际工程为例,求得隔震结构的各项耗能情况,说明了基础隔震结构以减少地震输入和隔震层滞回耗能来减小对上部结构的损坏。     

一种新型耗能剪力墙的滞回曲线计算分析

为了验证一种耗能剪力墙的抗震控制效果,本文进行了这种剪力墙模型的低周反复荷载试验。利用多垂直杆元模型建立了耗能剪力墙的力学计算模型,并利用该模型建立了计算耗能剪力墙荷载－位移骨架曲线和滞回曲线的计算方法,编制了相应的计算程序,利用该程序对试验进行了分析。计算曲线与试验曲线一致,表明本文采用的计算模型是正确的。     

设置黏滞阻尼器的钢结构实用减震设计方法

黏滞阻尼器作为一种有效的消能减震装置,已在钢结构建筑中得到了大量应用.然而由于钢结构的延性和阻尼特征,实用的钢结构附加黏滞阻尼器设计方法仍需深度探讨.文中提出一种基于黏滞阻尼器延性需求的减震设计方法.首先,根据钢结构需求量化层间位移角性能目标及目标附加阻尼比,计算黏滞阻尼器延性需求,并确定黏滞阻尼器布置数量、进行控制效...     

An innovative methodology for seismic retrofitting of existing RC buildings by metal shear panels

In the present paper, the seismic upgrading of existing reinforced concrete (RC) structures by means of steel and pure aluminium shear panels is examined. After a preliminary experimental evaluation of the performance of the bare RC structure, a design approach based on the capacity spectrum method has been developed according to the procedure provided in the ATC 40 American guidelines. First, the geometrical configuration of the applied shear panels has been defined according to simplified analytical relationships, while appropriate steel members have been designed to allow the insertion of shear panels in the existing RC structure. Then, complex finite element models have been implemented in order to check the reliability of the proposed design procedure. Also, a numerical evaluation of the global response of the upgraded structure has been processed aiming at evaluating the interaction between the RC structure and the metal devices. Finally, the effectiveness of the applied shear panels has been proven by means of full‐scale experimental tests, which confirmed the significant improvement of the RC structure performance, in terms of strength, stiffness and deformation capacity. Copyright © 2008 John Wiley & Sons, Ltd.     

The seismic behaviour of cross-braced steel frames

Analytical studies on the inelastic behaviour of concentrically braced steel frames for low-rise buildings are described in this paper. The bracing members which provide energy dissipation were used to provide information on the ductility levels that are likely to occur under differing levels of earthquake excitation. An indication of the relative performance of cross bracing is provided in terms of suitable SM values for use in the seismic provisions of New Zealand loadings code NZS 4203.     

型钢混凝土柱受剪承载力的统一计算公式

随着高强、超高强混凝土应用于型钢混凝土结构,型钢混凝土柱受剪承载力的计算缺乏统一的计算公式。为了能够反映型钢混凝土柱的实际受力,提出了以混凝土抗拉强度为基础、考虑型钢与混凝土共同工作的受剪承载力公式。公式形式简单并且能够与《混凝土结构设计规范》(GB50010-2002)衔接,适用于工程实践。通过77根型钢高强、普强混凝土柱的对比分析,计算结果与试验结果吻合。公式可应用于混凝土强度在C30~C80之间的型钢混凝土柱,可以将型钢普强混凝土柱和型钢高强混凝土柱的受剪承载力计算统一,因此可称之为型钢混凝土柱受剪承载力的统一计算公式。     

Experimental and analytical study on seismic behavior of steel-concrete multienergy dissipation composite shear walls

In this paper, a steel-concrete multi-energy dissipation composite shear wall, comprised of steel-reinforced concrete(SRC) columns, steel plate(SP) deep beams, a concrete wall and energy dissipation strips, is proposed. In order to study the multi-energy dissipation behavior and restorability after an earthquake, two stages of low cyclic loading tests were carried out on ten test specimens. In the first stage, test on five specimens with different number of SP deep beams was carried out, and the test lasted until the displacement drift reached 2%. In the second stage, thin SPs were welded to both sides of the five specimens tested in the first stage, and the same test was carried out on the repaired specimens(designated as new specimens). The load-bearing capacity, stiffness, ductility, hysteretic behavior and failure characteristics were analyzed for both stages and the results are discussed herein. Extrapolating from these results, strength calculation models and formulas are proposed herein and simulations using ABAQUS carried out; they show good agreement with the test results. The study demonstrates that SRC columns, SP deep beams, concrete wall and energy dissipation strips cooperate well and play an important role in energy dissipation. In addition, this study shows that the shear wall has good recoverability after an earthquake, and that the welding of thin SP’s to repair a deformed wall is a practicable technique.     

带缝空心保温RC剪力墙耗能性能试验研究

为研究带缝空心保温钢筋混凝土剪力墙的耗能性能,设计并制作了3组钢筋混凝土空心保温剪力墙。通过水平低周反复荷载试验,研究了该剪力墙的破坏机理、滞回特性、延性与耗能性能等力学性能,分析了竖缝形式、连接键等对空心保温剪力墙耗能性能的影响。研究表明:设置竖缝和连接键可以改变剪力墙的受力模式,使剪力墙在刚度和承载力下降较小的情况下,延性和抗震性能得到较大提高。由于耗能机理的转变,连接键、竖缝内的钢筋和橡胶带参与耗能,较大程度地提高剪力墙的耗能性能。     

不同延性条件下框架柱塑性铰区箍筋抗剪能力试验研究

允许钢筋混凝土框架柱端出现塑性铰但又不形成柱铰破坏机构是一个十分现实而又未得以很好解决的课题。通过10个钢筋混凝土框架柱构件抗震剪切抗力的试验研究,明确了加载全过程骶架柱构件中箍筋与混凝土的抗剪贡献及比例,分析了框架柱塑性铰区抗剪机理,为框架柱基于延性的抗震设计提供了试验依据。