共查询到19条相似文献，搜索用时 703 毫秒
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本文采用有限元程序对设有错位转换的高层结构进行了空间时程地震反应分析,论述了错位转换层整体位置、错位转换层相对位置对结构动力特性、动力反应及竖向构件内力的影响。分析结果表明,错位转换层整体位置的变动及相对变动对结构周期、主要振型和相对位移影响不大;随着错位转换层整体向上移动,在转换层处的层间位移角的突变会加剧;当两错位转换层相距3层左右时,高层结构地震反应最不利;错位转换层的存在会使两错位转换层附近的竖向构件内力发生突变,设计中应予以加强。 相似文献
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带耗能腋撑竖向不规则短肢剪力墙结构减震性能分析 总被引：2，自引：0，他引：2
在不影响建筑使用空间前提下,提出在抗侧构件不连续处设置耗能腋撑以改善竖向不规则结构抗震性能。以底部大空间短肢剪力墙结构为研究对象,利用大型通用有限元程序ETABS研究耗能器类型与场地土对耗能腋撑工作性能和竖向不规则结构受力性能的影响。研究表明,黏滞型耗能腋撑对文中分析模型各楼层地震反应有较好的控制效果,对转换层处层间位移角与层剪力最大值减幅最大,分别为40.14%和15.66%,对顶层加速度与基底剪力峰值的最大减幅分别为16.06%和23.57%,黏滞型耗能腋撑最大能耗散输入结构能量的42%,而黏弹型耗能腋撑对结构的控制效果不理想;当地震震级较大、震中距较小时,耗能腋撑对坚硬与软弱场地土的模型结构控制作用相差不大,减震位移比在转换层处达到最小值0.76;随着震级减小或震中距增大,耗能腋撑对该模型结构的控制作用随场地土变硬而逐渐增强,其减震位移比介于0.68～0.74之间。 相似文献
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高层隔震建筑的隔震层在罕遇地震作用下会产生拉应力。本文通过对一栋20层的高层隔震结构,分别采用等拉压刚度模型和不等拉压刚度模型进行动力非线性时程分析,研究叠层橡胶隔震支座竖向刚度模型对高层基础隔震结构动力响应的影响。研究表明,超出线弹性工作范围后,竖向等拉压刚度模型将会低估隔震层的竖向位移量,低估上部结构的动力响应。 相似文献
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《地震工程与工程振动》2017,(6)
本文选取两栋高层剪力墙结构住宅工程案例,采用ETABS软件分析并讨论了高层剪力墙结构中安装位移型钢滞变阻尼器连梁进行消能减震设计的几个关键问题。以阻尼器刚度、设计极限位移、附加阻尼比等参数为基本参量,以层间位移角和层间剪力为减震效果优劣评价指标,对比研究了阻尼器空间布设位置和数量变化对结构地震反应的影响规律。验证了阻尼器刚度参数变化影响结构主振周期变化,进一步影响层间剪力减震效果;阻尼器设计极限位移参数变化引起结构整体耗能能力变化,即阻尼器的设置增加了结构附加阻尼比尤其是大震附加阻尼比,使结构大震作用下的层间位移反应得到有效控制。给出了如下设计建议:当在高层剪力墙结构中采用消能连梁进行消能减震设计时,应尽可能将阻尼器布置在受力较大的连梁位置处,并使阻尼器的设计屈服位移和极限位移分别与结构设计弹性层间位移和弹塑性层间位移相匹配。在设计过程中应通过调整阻尼器刚度尽可能延长消能减震结构的基本振动周期,优化阻尼器布设位置和数量,最大限度地增大阻尼器对结构的附加阻尼比贡献,达到显著降低结构地震反应的目的。 相似文献
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基于概率和位移的框支剪力墙结构抗震性能评估方法 总被引：1，自引：0，他引：1
本文严格按照中国规范设计出典型的带转换层部分框支剪力墙钢筋混凝土结构,通过弹塑性分析程序IDARC2D对该结构进行多个地震动作用下的大震弹塑性时程分析,得到结构及各个构件的反应量的统计特征,再参照美国基于性能抗震设计规范ASCE-41-06的结构与构件变形限值作为性能指标,计算出结构和各个构件的可靠度和可靠指标,作为评价结构抗震性能的标准,总结归纳出基于概率和位移的抗震设计方法的思路.最后运用该方法,对7、8度烈度区的框支剪力墙结构进行可靠性分析,通过对比分析,研究考虑内力增强措施、层间位移角控制条件、竖向构件轴压比限制条件、层刚比控制准则和竖向构件最小配筋率等因素对不同抗震烈度区的框支剪力墙结构的可靠性的影响,从而评价中国规范抗震措施和构造措施的有效性. 相似文献
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现阶段基于性能的抗震设计思想不仅关注结构自身体系的安全,而且保护非结构构件在地震作用下使用功能完好。对于工业建筑结构,生产设备在地震作用下受损会影响震后功能恢复。加速度敏感型非结构构件一般采用楼层加速度指标来量化其地震损伤程度。以三个不同高度的钢抗弯框架规则结构体系为研究对象,采用与竖向目标谱匹配的近断层非脉冲和脉冲地震动作为竖向地震输入,考察不同质量不规则程度下,楼层竖向绝对加速度随建筑高度的变化趋势,并从反应谱角度分析不规则质量分布对楼层加速度响应的影响。结果表明:4层结构在非脉冲地震作用下楼层顶层处竖向绝对加速度是地面竖向峰值加速度的5倍之多,某一层质量的突变会引起该层及其他楼层竖向绝对加速度的明显变化。另外,对现有计算楼层竖向加速度响应的经验公式进行验证,发现美国ASCE 7-16规范的估计结果偏于保守。 相似文献
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根据中国规范设计了一总层数为40层的错位转换高层建筑结构,为对比分析需要另设计具有相同楼层数的两带单层转换高层建筑结构。采用Etabs和Satwe对比分析了三结构在水平地震作用下的相对位移比、层间位移比沿楼层分布情况;其相对扭转角、层间扭转角、层间有害扭转角的分布特点;顶层角点扭转位移轨迹。研究分析表明,错位转换高层结构的扭转反应远大于同类带单层转换高层结构的反应;对单层转换结构采用位移比不能很好反映其扭转反应,而结构扭转位移角沿楼层分布规律更能体现其扭转反应特征。 相似文献
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近场地震的动力特性明显不同于远场地震,因此有必要对结构在近场地震作用下的动力性能展开研究。以上部钢结构-下部混凝土结构这类竖向刚度不同的加层混合结构为研究对象,对其在近场脉冲型地震、近场无脉冲型地震及远场地震作用下的动力响应进行研究。结果表明:在多遇、设防、罕遇地震作用下,近场脉冲型地震会使结构的层间位移角、层间剪力、加速度等动力响应均放大并出现超限的情况,而且都比罕遇地震作用下结构的响应增大更明显;在进行近场区加层混合框架结构的设计和建设时,近场脉冲效应会使结构存在不满足规范的情况,有必要对竖向刚度不同的加层混合结构在近场区的适用性进行深入研究。 相似文献
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西方嵩层框支剪力墙结构地震反应分析的超元法，即将每榀框支墙中的上部剪力墙和落地墙简化处理成等效柱，底部框架简化处理成等代柱，楼板视为深梁，将连续分布的质量离散化，建立二维空间结构的“串并联质点系”振动模型，采用超级单元进行结构的地震作用计算及内力分析，此法计算简便并适用于结构竖向变刚度和考虑楼板变形等情况。 相似文献
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基于能力设计原理的双肢剪力墙极限承载力研究 总被引：1，自引：0，他引：1
通过对双肢剪力墙的静力推覆分析(Push-over分析)揭示其极限状态的多种形式并提出连梁强度折减系数K,对在理想极限状态下的连梁剪力超强进行折减,得出对应于不同极限状态下连梁对墙肢轴力的改变量,可用于双肢剪力墙结构超强的整体计算,为带转换层的高层建筑转换结构的能力设计提供了理论基础。 相似文献
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Major damage has been reported in hilly areas after major earthquakes,primarily because of two special conditions:the variation in the seismic ground motion due to the inclined ground surface and the irregularities caused by a stepped base level in the structure.The aim of this study is to evaluate possible differences in the responses of Chilean hillside buildings through numerical linear-elastic and nonlinear analyses.In the first step,a set of response-spectrum analyses were performed on four simplified 2D structures with mean base inclination angles of 0°,15°,30°,and 45°.The structures were designed to comply with Chilean seismic codes and standards,and the primary response parameters were compared.To assess the seismic performance of the buildings,nonlinear static(pushover)and dynamic(time-history)analyses were performed with SeismoStruct software.Pushover analyses were used to compare the nonlinear response at the maximum roof displacement and the damage patterns.Time-history analyses were performed to assess the nonlinear dynamic response of the structures subjected to seismic ground motions modified by topographic effects.To consider the topographic modification,acceleration records were obtained from numerical models of soil,which were calculated using the rock acceleration record of the Mw 8.01985 Chilean earthquake.Minor differences in the structure responses(roof displacements and maximum element forces and moments)were caused by the topographic effects in the seismic input motion,with the highly predominant ones being the differences caused by the step-back configuration at the base of the structures.High concentrations of shear forces in short walls were observed,corresponding to the walls located in the upper zone of the foundation system.The response of the structures with higher angles was observed to be more prone to fragile failures due to the accumulation of shear forces.Even though hillside buildings gain stiffness in the lower stories,resulting in lower design roof displacement,maximum roof displacements for nonlinear time-history analyses remained very close for all the models that were primarily affected by the drifts of the lower stories.Additionally,vertical parasitic accelerations were considered for half the time-history analyses performed here.The vertical component seems to considerably modify the axial load levels in the shear walls on all stories. 相似文献
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Gaps between beam‐to‐column interfaces in a post‐tensioned (PT) self‐centering frame with more than one column are constrained by columns, which causes beam compression force different from the applied PT force. This study proposes an analytical method for evaluating column bending stiffness and beam compression force by modeling column deformation according to gap‐openings at all stories. The predicted compression forces in the beams are validated by a cyclic analysis of a three‐story PT frame and by cyclic tests of a full‐scale, two‐bay by first‐story PT frame, which represents a substructure of the three‐story PT frame. The proposed method shows that compared with the strand tensile force, the beam compression force is increased at the 1st story but is decreased at the 2nd and 3rd stories due to column deformation compatibility. The PT frame tests show that the proposed method reasonably predicts beam compression force and strand force and that the beam compression force is 2 and 60% larger than the strand force with respect to a minor restraint and a pin‐supported boundary condition, respectively, at the tops of the columns. Therefore, the earlier method using a pin‐supported boundary condition at upper story columns represents an upper bound of the effect and is shown to be overly conservative for cases where a structure responds primarily in its first mode. The proposed method allows for more accurate prediction of the column restraint effects for structures that respond in a pre‐determined mode shape which is more typical of low and mid‐rise structures. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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This paper describes shaking table tests of three eight-story building models: all are masonry structures in the upper stories, with or without frame-shear walls of one- or two- stories at the bottom. The test results of damage characteristics and seismic responses are provided and compared. Then, nonlinear response analyses are conducted to examine the reliability of the dynamic analysis. Finally, many nonlinear response analyses are performed and it is concluded that for relatively hard sites under a certain lateral stiffness ratio (I.e., the ratio of the stiffness of the lowest upper masonry story to that of the frame-shear wall story), the masonry structure with one-story frame-shear wall at the bottom performs better than a structure built entirely of masonry, and a masonry structure with frame-shear wall of two stories performs better than with one-story frame-shear wall. In relatively soft soil conditions, all three structures have similar performane. In addition, some suggestions that could be helpful for design ofmasomy structures with ground story of frame-shear wall structure in seismic intensity region VII, such as the appropriate lateral stiffness ratio, shear force increase factor of the frame-shear wall story, and permissible maximum height of the building, are proposed. 相似文献
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随着中国汽车工业的发展,大量废旧轮胎带来的"黑色污染"问题日益显著。提出一种采用废旧轮胎柱(Scrap tire columns,STC)的加筋土结构,并初步探究其作为基础减隔振材料的可行性。通过室内水平循环剪切试验和竖向激振试验研究STC加筋砂(STCRS)的水平循环剪切和竖向激振特性。结果表明,最大剪应变为1%时STCRS的等效阻尼比未加筋前增加约10%,等效动剪切模量减小20%~25%,水平向减振性能得以提高;STCRS的竖向加速度衰减呈现出速度快、幅值大的特点,竖向减振效果较未加筋砂显著提高。STC加筋砂作为基础减振材料是可行的,且为原形废旧轮胎的资源化利用提供新思路。 相似文献
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大开间小型混凝土砌块10层模型房屋抗震性能试验研究(Ⅰ) 总被引：8，自引：3，他引：8
我国抗震设计规范（GB50011－2001）规定在6、7、8度区，混凝土小砌块结构分别可以建七、六、五层。由于混凝土小砌块结构的最大优势在于10－20层（与混凝土框架或框架剪力墙结构比）。本文按1／4比例制作了10层混凝土小砌块结构模型，按7度设防要求实施构造措施，通过振动台试验研究模型结构的抗震性能。结果表明，模型结构完全能够满足在7度区“小震不坏，大震不倒”的要求。圈梁、构造柱以及水平拉结筋构成的约束体系抗震作用是明显的。试验利用砌块的非注芯孔灌注铁砂来模拟墙体出平面动力效应。在本模型的构造措施下，平出面反应不对结构破坏起控制作用。 相似文献
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Chao‐Hsien Li Keh‐Chyuan Tsai Jing‐Tang Chang Chih‐Han Lin Jia‐Chian Chen Te‐Hung Lin Pei‐Ching Chen 《地震工程与结构动力学》2012,41(9):1277-1299
Coupled steel plate shear wall (C‐SPSW) consists of two or more steel plate shear walls interconnected by coupling beams at the floor levels. In this study, a six‐story C‐SPSW prototype building was designed. A 40% scale C‐SPSW specimen, which is representative of the bottom two‐and‐half‐story substructure of the prototype, was cyclically tested using Multi‐Axial Testing System at the National Center for Research on Earthquake Engineering in 2009. In addition to a constant vertical force representing the gravity load effects, cyclic increasing displacements and the corresponding overturning moments transmitted from the upper stories were computed online and simultaneously applied on the substructural specimen. This paper firstly introduces the designs of the prototype C‐SPSW and the test specimen. Then, the test results and the numerical simulation are discussed in detail. Test results confirm the effectiveness of the proposed column capacity design method, which aims at limiting the plastic hinge formation within the bottom quarter height of the bottom column. Test and analytical results suggest that the coupling beam rotational demands can be estimated as the design story drifts when the formation of desirable plastic mechanism of the C‐SPSW is expected. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Near‐fault ground motions with forward directivity are characterized by a large pulse. This pulse‐like motion may cause a highly non‐uniform distribution of story ductility demands for code‐compliant frame structures, with maximum demands that may considerably exceed the level of code expectations. Strengthening techniques for multi‐story frame structures are explored with the objective of reducing maximum drift demands. One option is to modify the code‐based SRSS distribution of story shear strength over the height by strengthening of the lower stories of the frame. The modified distribution reduces the maximum story ductility demand, particularly for weak and flexible structures. However, this strengthening technique is less effective for stiff structures, and is almost ineffective in cases in which the maximum demand occurs in the upper stories, i.e. strong and flexible structures. As an alternative, the benefits of strengthening frames with elastic and inelastic walls are evaluated. The effects of adding walls that are either fixed or hinged at the base are investigated. It is demonstrated that strengthening with hinged walls is very effective in reducing drift demands for structures with a wide range of periods and at various performance levels. Wall inelastic behavior only slightly reduces the benefits of strengthening with hinged walls.Copyright © 2004 John Wiley & Sons, Ltd. 相似文献