消能支撑加固底部框架砌体房屋的弹塑性地震反应分析

本文采用弹塑性时程分析方法,对底部框架多层砌体房屋在不同烈度罕遇地震作用下进行了抗震性能评估;研究了在底部框架内增设消能外包混凝土无粘结钢支撑对房屋抗震性能的影响;对增设消能支撑加固方案和增设抗震墙加固方案进行了对比分析。分析结果表明,在底层框架砌体房屋的底层增设消能支撑可显著降低底层框架的最大层间位移,控制结构的塑性损伤,提高结构的抗震性能。增设消能支撑加固方案与增设抗震墙加固方案相比,结构加固更合理、更易实施。     

Practical modelling issues for masonry building retrofitted with squat shear wall

Damage observed following moderate to large earthquakes has shown masonry buildings are vulnerable to lateral shaking. The results of statistical analyses in Iran show that 90% of schools in the retrofitting list are unreinforced masonry buildings. A Practical Guideline for Seismic Rehabilitation of Masonry Schools has been published in Iran. This guideline proposed 2 retrofitting methods for retrofitting masonry schools: use of shear wall and shotcreting the perimeter of building. In the case of shear wall, their construction is usually expensive; there are less projects retrofitted by shear walls, and in most retrofitting masonry schools projects, perimeter shotcrete is used. The main aim of this study is offering recommendation to improve this guideline, resulting in more economical approaches. This study proposes including lateral resistance of masonry walls in resisting seismic loads and in the case of shear wall foundation proposes strip shallow foundation for concrete shear walls by including effect of rocking, sliding, and settlement response. It has been shown that with including masonry walls in lateral resistance of building, a considerable reduction in maximum drift occurred. Interaction of soil and structure by considered strip shallow foundation reduces the base shear and increases maximum drift of the building.     

日本结构抗震加固的工程实例

本文由株式会社日建设计的结构设计部工程师具体介绍了一些地震加固工程实例。由于日本是多地震国家,不仅在结构设计时要求建筑物在地震后易于加固,而且在结构加固时也要求加固得足以抵抗将来可能发生的更强烈的地震,以保证建筑物的耐久性能。在日本,抗震理论和技术年复一年地提高,这里,主要介绍两种地震加固的方法—制振和隔震。实例1是采用含低屈服点钢材的吸能支撑(Energy Absorption Bracing,EAB)来进行地震加固的例子。该建筑建造于1970年,是一个64m高的型钢骨混凝土结构(Steel framed Re-inforced Concrete,SRC)。实例2是建于1920年的一所大学的小礼拜堂。这个2层的建筑高12.6m,由砖建成。在经过多方调查后,提出了三种方案来对其进行地震加固,最终选用了基底隔震技术来使得建筑上部的钢筋用量最小。实例3是一个国际儿童文献图书馆的改造工程,该图书馆成功地保留了原来建筑的历史价值,并且又增加了很多当代图书馆的新功能。在该工程中采用了基底隔震技术。     

波形钢板-混凝土组合剪力墙抗震性能试验研究

为研究波形钢板-混凝土组合剪力墙的抗震性能,完成了竖向波形钢板-混凝土组合剪力墙、水平波形钢板-混凝土组合剪力墙以及平钢板-混凝土组合剪力墙拟静力试验,研究了波形钢板-混凝土组合剪力墙在低周往复荷载作用下的变形能力和破坏模式,分析了荷载-位移滞回曲线、骨架曲线、各阶段特征荷载和位移值等,以及结构的破坏特征、变形和耗能能力、刚度和承载力退化。试验结果表明：波形钢板-混凝土组合剪力墙具有较大的抗侧刚度、较好的延性和耗能能力;与平钢板-混凝土组合剪力墙相比,波形钢板-混凝土组合剪力墙有较好的界面黏结性能,而平钢板-混凝土剪力墙由钢板变形引起的混凝土剥落严重;波形钢板-混凝土组合剪力墙的初始刚度较平钢板-混凝土组合剪力墙的高,竖向波形钢板-混凝土组合剪力墙的承载力和极限位移较水平波形钢板-混凝土组合剪力墙的高,波形钢板-混凝土组合剪力墙的承载力退化和刚度退化比平钢板-混凝土组合剪力墙的慢,表现出较好的受力性能。采用ABAQUS有限元软件可以较好地模拟试验,有限元分析结果表明,波形钢板的应力分布比较均匀,组合作用效应明显,适合在抗震结构中采用。     

低剪跨比双钢板-混凝土组合剪力墙抗震性能试验研究

为研究低剪跨比双钢板-混凝土组合剪力墙的抗震性能,完成了2片低剪跨比双钢板-混凝土组合剪力墙和1片低剪跨比钢筋混凝土剪力墙试验,研究了高轴压比剪力墙在低周往复荷载作用下的变形能力、破坏模式,得到了试件滞回曲线、骨架曲线、承载力、位移延性系数、刚度退化、承载力退化和耗能能力等,分析了不同形式连接件对抗震性能的影响。试验结果表明：与钢筋混凝土剪力墙相比,低剪跨比双钢板-混凝土组合剪力墙受剪承载力显著提高,具有良好的延性和耗能能力,抗震性能良好。     

磁流变阻尼智能加固体系的试验研究

提出利用磁流变阻尼器(MRD)对有损伤结构进行智能加固。根据MRD的特点,结合我国抗震设计规范,给出MRD智能加固的三个等级性能目标,对其进行量化,并确定MRD智能加固的设计要点。利用MRD对一有损伤钢筋混凝土框-剪偏心结构进行抗震加固,并进行振动台试验。结果表明,采用MRD智能加固后的结构抗震性能大大提高,优于用被动控制方法加固的结构。     

边缘配置高强纵筋装配式中高强再生混凝土剪力墙抗震性能研究#br#

为促进高性能绿色建筑结构发展,推动高强钢筋和中高强再生混凝土的工程应用,研发了边缘构件采用环筋扣合连接方式且配置高强纵筋的装配式中高强再生混凝土剪力墙,对6个剪跨比为2.2的装配式混凝土剪力墙进行了低周反复荷载试验。分析了不同再生粗骨料取代率、混凝土强度、边缘暗柱纵筋强度及搭接位置对装配式再生混凝土剪力墙的破坏形态、滞回性能、承载力、延性、刚度退化规律、耗能能力等抗震性能指标以及可恢复性能的影响。试验结果表明：边缘构件配置高强钢筋的装配式中高强再生混凝土剪力墙的破坏形态以弯曲破坏为主;再生粗骨料取代率对装配式中高强再生混凝土剪力墙的承载力、延性和耗能能力影响不大,各剪力墙均具有较好的抗震性能;边缘暗柱采用HRB600纵筋可有效提高装配式中高强再生混凝土剪力墙的承载力、耗能能力和可恢复性能;边缘暗柱纵筋在剪力墙底部塑性铰区搭接,会导致装配式中高强再生混凝土剪力墙的延性明显下降。给出了边缘配置HRB600纵筋的装配式中高强再生混凝土剪力墙水平承载力计算式,计算结果表明普通混凝土剪力墙的水平承载力计算模型同样适用于该装配式剪力墙结构。     

纯剪荷载作用下帽型冷弯薄壁型钢屈曲约束钢板墙元的抗震性能试验研究

提出了一种帽型冷弯薄壁型钢屈曲约束钢板剪力墙结构抗侧力体系。为了研究该帽型冷弯薄壁型钢屈曲约束钢板剪力墙结构的抗震性能,剥离了钢板剪力墙结构抗侧力体系中梁柱框架刚接对体系抗侧力的贡献,从钢板剪力墙中提取出“墙元”,并保证其为纯剪受力状态,设计了5个帽型冷弯薄壁型钢屈曲约束钢板剪力墙墙元试件,对其进行往复剪切荷载下的拟静力试验。结果表明：帽型冷弯薄壁型钢屈曲约束钢板剪力墙结构承载能力稳定,位移延性系数达到7以上,极限位移角达0.03rad,塑性变形能力较强;帽型冷弯薄壁型钢可以阻断内嵌钢板斜向通长拉力带,使钢板约束覆盖区域处于平面剪切受力变形状态,从而提升结构承载力、刚度和耗能能力,充分发挥钢板的材料性能;外贴OSB装饰板材可以满足建筑功能的适用性,同时强化了整体结构的抗震性能。     

钢板焊接连接的带水平接缝装配式RC剪力墙抗震性能试验研究

为了研究采用钢板焊接连接的带水平接缝预制装配式钢筋混凝土剪力墙的抗震性能,设计了4个装配式钢筋混凝土剪力墙足尺试件并进行低周往复水平荷载试验,研究参数包括连接钢板厚度、侧向钢板设置和轴压比。结果表明：各试件均为压弯破坏,水平承载力在186~288kN之间,极限位移在25.74~29.37mm之间,滞回曲线为饱满的弓形,延性和耗能能力较好,刚度退化较慢;在连接钢板满足强度要求前提下,增大连接钢板厚度、增加侧向钢板对剪力墙的延性、刚度、承载能力和耗能能力影响较小;提高轴压比可以明显提高装配式剪力墙的刚度和承载能力,但会降低其耗能能力。采用ABAQUS有限元软件对装配式剪力墙抗震性能进行分析,所建立的有限元模型可以较好地模拟装配式剪力墙的受力性能。通过对比采用规范公式计算的承载力与试验承载力,表明可以采用JGJ 3—2010《高层建筑混凝土结构技术规程》中的公式计算文中装配式剪力墙的承载力,并给出了连接钢板的计算方法。     

Optimal seismic upgrading of a reinforced concrete school building with metal-based devices using an efficient multi-criteria decision-making method

In the paper, the seismic retrofitting of an existing reinforced concrete school building located in the district of Naples has been examined. The school, which was designed to sustain gravity load only, is composed of seven constructions separated with seismic joints. One of these constructions has been retrofitted with different intervention techniques, namely reinforced concrete walls, steel concentric, eccentric and buckling restrained braces and steel shear panels, whose non-linear behaviour under seismic actions in terms of performance point detection have been evaluated and compared using Capacity Spectrum Method. Finally, the choice of the best intervention technique from economic, structural and environmental point of view has been done utilising an efficient multi-criteria decision-making (MCDM) method, the so-called TOPSIS method. From the performed analyses it was found that buckling restrained braces provide optimal solution for the seismic upgrading of the examined reinforced concrete school building.     

四川烟草兴业大厦结构设计

四川烟草兴业大厦为一超高层混合结构,采用矩形钢管混凝土柱框架-钢筋混凝土核心筒结构体系.结合工程特点,详细介绍了结构设计过程中结构布置、计算分析、主要抗震加强措施、竖向变形差的处理等方面的内容,可供类似工程设计参考.     

高轴压比下内置钢板高强混凝土组合剪力墙#br# 抗震性能试验研究

内置钢板混凝土组合剪力墙主要应用于超高层建筑结构中,是主要的抗侧力构件,其底部剪力墙往往承担巨大的竖向荷载,轴压比和混凝土强度是影响其抗震性能的主要因素。为研究内置钢板高强混凝土组合剪力墙在高轴压比下的抗震性能,进行2个剪跨比为2.28的组合剪力墙试件拟静力试验,设计轴压比分别为0.6和0.8,C70混凝土。研究组合剪力墙在低周反复荷载作用下的受力性能和破坏模式,分析轴压比对抗震性能的影响。结果表明：2个试件最终均发生压弯破坏,破坏截面基本符合平截面假定,滞回曲线均较饱满,耗能性能良好,同时具有比较稳定的水平承载力;随着轴压比增大,组合剪力墙的水平承载力、初始刚度和耗能能力增大,侧向变形能力有所降低,但屈服位移角仍大于1/120,极限位移角为1/46。研究可为内置钢板高强混凝土组合剪力墙的工程应用提供理论参考。     

预制装配式型钢混凝土剪力墙试验对比研究

采用对比试验研究方式,通过对同尺寸、同配筋的现浇式型钢混凝土剪力墙试件和预制装配式型钢混凝土剪力墙试件的低周往复加载试验,研究了预制装配式型钢混凝土剪力墙的承载能力、滞回性能、刚度退化等抗震性能,以及灌浆销栓式套筒连接节点对型钢混凝土剪力墙抗震性能的影响趋势。结果表明,预制装配式型钢混凝土剪力墙的承载能力、刚度、耗能性能均略低于现浇式型钢混凝土剪力墙,但基本能够满足结构承载和抗震要求;对连接节点的分析可知,除了销栓的抗剪能力外,加强销栓与套筒和型钢之间的紧固,可以更好的提升套筒的连接性能。     

不同分布筋间距下型钢混凝土剪力墙抗震性能试验

为研究分布筋间距对型钢混凝土剪力墙抗震性能的影响,设计了4个矩形截面型钢混凝土剪力墙试件（其中1个为不带暗撑的普通剪力墙对比试件,3个为带X形暗撑的型钢混凝土剪力墙试件）,进行了低周反复荷载试验。结果表明:型钢混凝土剪力墙试件的承载力随着分布筋间距的增大而减小,其分布筋间距为100,150,200 mm的试件承载力较对比试件分别提高了66.8%,45.9%和41%;型钢混凝土剪力墙试件的延性随着分布筋间距的增大而呈线性降低趋势,其分布筋间距为100,150,200 mm的试件延性系数较对比试件分别提高了27.8%,29.2%和11.3%;试件的分布筋间距越小其裂缝越细密,沿暗支撑走向分布越明显,塑性铰范围越大,耗能能力越高,抗震性能越好。     

钢框架-混凝土核心筒结构框架地震设计剪力标准值研究

为研究双重体系钢框架-混凝土核心筒结构的框架设计地震剪力标准值,对20个钢框架-混凝土核心筒结构模型进行了静力弹塑性分析。从承载力、结构失效模式和框架破损程度三个方面评价20个计算模型的抗震能力。根据推覆分析结果,提出了如下设计建议:8度抗震设防时钢框架-混凝土核心筒结构的刚度特征值λ大于0.65,各层框架的设计地震剪力标准值不小于本层总剪力的18%和不小于框架-核心筒结构计算得到的地震剪力的1.2倍(加强层和顶层的剪力可不小于框架-核心筒结构计算得到的地震剪力),框架角柱轴压比不大于0.5。算例表明,符合建议的钢框架-混凝土核心筒结构,在地震作用时不会出现不合理的破坏形态。     

不同钢—混凝土组合剪力墙抗震性能对比分析

钢—混凝土组合剪力墙中钢板的布置形式是影响其抗震性能的一个主要因素。通过对两组内置钢板混凝土组合剪力墙和内藏钢桁架混凝土组合剪力墙试验的模拟,确定计算模型的建立方法,并选取两片相同含钢率的内置钢板混凝土组合剪力墙和内藏钢桁架混凝土组合剪力墙进行在侧向低周反复荷载作用下的计算分析,对比了两片剪力墙的承载力、刚度及其退化过程、延性、耗能特性及滞回特性。研究结果表明:在相同含钢率的条件下,内藏钢桁架混凝土组合剪力墙与内置钢板混凝土组合剪力墙相比,承载力、延性、耗能能力均有较明显提高。     

配置斜筋的单排配筋混凝土低矮剪力墙动力性能试验研究

在单排配筋混凝土低矮剪力墙的墙体或底部配置斜筋,可限制墙体斜裂缝开展,提高剪力墙的基底抗剪切滑移能力,改善其抗震性能。为了解不同斜筋布置形式对其动力性能与地震损伤破坏机理的影响,进行了3个不同配筋形式的混凝土低矮剪力墙模型振动台试验,包括1个普通单排配筋混凝土剪力墙,1个墙体内配置45°斜筋的单排配筋混凝土剪力墙,1个墙体底部配置45°斜筋的单排配筋混凝土剪力墙。在试验基础上,分析了3个剪力墙模型在弹性、开裂及弹塑性损伤破坏等不同受力阶段的自振特性与地震反应,比较了其破坏形态和加速度、位移时程反应。研究结果表明,配置斜筋能有效地提高单排配筋混凝土低矮剪力墙的抗震能力。     

Experimental study on seismic behavior of mid-rise RC shear wall with concealed truss

In this paper, mid-rise shear wall with concealed truss was proposed. This new composite shear wall includes two kinds of composition: one is the composition of two bearing systems, including truss and shear wall, and the other is the composition of two materials, including steel and concrete. Therefore, it is a double composite shear wall. The experimental study on the seismic behavior of six 1/3 scale mid-rise shear walls, including an ordinary mid-rise shear wall, a mid-rise shear wall with steel frame, and four mid-rise shear wall with concealed truss made of different materials, was studied. Based on the experimental study, the stiffness and its attenuation, bearing capacity, ductility, hysteretic property, energy dissipation, and failure phenomena of each shear wall were contrastively analyzed. The formulas of bearing capacity and stiffness were established. The results obtained from the formulas and those from experiment are in good agreement. Some suggestions for seismic design of shear wall are given in this paper. The experimental results show that the seismic behavior of the mid-rise shear wall with steel frame and that of every truss with different materials is obviously improved.     

广州珠江新城J1-1地块综合楼超高层建筑结构设计

广州J1-1地块综合楼超高层建筑采用圆钢管混凝土柱-钢梁外框架和新型方钢管混凝土端柱+混凝土剪力墙组合墙体核心筒结构体系。基于概念设计,设定结构的抗震性能目标;弹塑性地震反应分析表明,结构设计达到了设定的性能目标;利用风洞试验结果,分析结构的风响应;对方钢管混凝土端柱-混凝土剪力墙新型组合墙体的抗震性能进行理论分析和试验研究。     

Experimental study on seismic behavior of mid-rise RC shear wall with concealed truss

In this paper, mid-rise shear wall with concealed truss was proposed. This new composite shear wall includes two kinds of composition: one is the composition of two bearing systems, including truss and shear wall, and the other is the composition of two materials, including steel and concrete. Therefore, it is a double composite shear wall. The experimental study on the seismic behavior of six 1/3 scale mid-rise shear walls, including an ordinary mid-rise shear wall, a mid-rise shear wall with steel frame, and four mid-rise shear wall with concealed truss made of different materials, was studied. Based on the experimental study, the stiffness and its attenuation, bearing capacity, ductility, hysteretic property, energy dissipation, and failure phenomena of each shear wall were contrastively analyzed. The formulas of bearing capacity and stiffness were established. The results obtained from the formulas and those from experiment are in good agreement. Some suggestions for seismic design of shear wall are given in this paper. The experimental results show that the seismic behavior of the mid-rise shear wall with steel frame and that of every truss with different materials is obviously improved.