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1.
为了避免立式储罐自复位滚动隔震体系的支座位移过大导致支座失效,同时达到在不同地震动作用下,减震效应明显的目的,设计了一种变刚度限位滚动隔震装置,以便适应地震动特性变化以及储液高度变化的影响。利用有限元分析软件ADINA进行数值仿真分析,采用弹簧-阻尼系统模拟隔震层,非线性弹簧单元模拟限位装置,流体采用势流体单元,罐壁采用壳单元,建立15×104m3储罐模型。在加速度峰值为0.4 g不同地震动激励下,尤其是近断层长周期地震作用下,对加入限位装置前后储罐的地震响应进行对比,结果表明:采用限位装置后,支座位移得到明显控制,基底剪力、基底弯矩以及动液压力却都有不同程度的放大,但相比非隔震情况下仍有较好的隔震效果,晃动波高略有增大。建议在采用变刚度滚动隔震措施时,可考虑综合减震方案,优化减震效果。  相似文献   

2.
橡胶支座基础隔震结构遭遇近断层脉冲型地震动作用时,隔震层变形过大,需要限位。提出了软碰撞限位方案。按抗震规范设计橡胶支座隔震钢筋混凝土框架结构,选取近断层地震动记录,分析了限位主要参数预留距离、限位刚度和阻尼对隔震结构响应的影响。结果表明,预留距离增大,限位刚度需求增大,限位效果减弱;限位刚度增大,隔震层最大位移减小,上部结构层间最大位移增大;在一定范围内适当增大阻尼可减小隔震层最大位移与上部结构的层间最大位移。合理选用限位参数,可同时获得良好的限位与减震效果。提出了限位参数的优选方法。  相似文献   

3.
以村镇建筑为研究对象,以能量法为基础,提出了滞回耗能比的概念,计算了结构在地震作用下的滞回耗能比,探讨了系统参数对滞回耗能比的影响,以此来分析带限位装置滑移隔震系统的村镇建筑的隔震层滞回耗能特性。研究表明:摩擦系数对滞回耗能比影响显著,刚度比、上部结构固有周期和限位装置的第2阶段刚度系数对滞回耗能比有一定的影响,而质量比和限位装置的屈服位移对滞回耗能比影响不显著。  相似文献   

4.
利用实体软钢棒作为消能限位装置,将一种摩擦性能优良的二硫化钼材料作为隔震支座的滑移材料,提出并制作了一种可以应用于框架结构既能隔震又可以消能的新型摩擦滑移隔震装置。探讨了其设计方法和应用方法,并对安装了该新型摩擦滑移隔震装置的一相似比为1:5的5层框架结构模型进行了振动台试验,测试了框架结构在单向地震波作用下的地震反应规律,分析了摩擦滑移隔震结构的加速度反应、层间剪力反应、隔震层滑移量及隔震层剪力的变化规律。结果表明:一般情况下当设防烈度为8度,Ⅱ类场地时,该隔震结构的加速度响应可降低50%左右,层间剪力响应可降低50%左右,减震效果比较明显。另外,只要确定合理的构造方案和实施方案,这种新型摩擦滑移隔震装置就能满足框架结构的隔震减震要求,可应用于实际工程结构中。  相似文献   

5.
近断层地震作用下基础隔震层组合限位振动台实验研究   总被引:1,自引:0,他引:1  
韩淼  孙欢  段燕玲 《地震学刊》2014,(1):107-112
近断层脉冲型地震作用下,基础隔震结构隔震层会产生过大变形,导致隔震支座侧倾失稳,隔震体系破坏。设计制作了3层基础隔震钢框架实验模型和11种U型钢板I型铅棒组合限位器,进行了U型钢板静力加载实验和近断层脉冲型地震作用下基础隔震层软碰撞限位振动台模型实验。实验表明:①静力加载时,U型钢板具有很好的弹性性能;②动力作用下,组合限位器残余变形较小,仍具有良好限位复位能力;③近断层地震作用下,基础隔震层软限位效果良好,同时控制上部结构层间变形在允许范围内。  相似文献   

6.
采用新型固体摩擦滑移材料二硫化钼作为涂层材料,利用实体软钢棒作为限位消能装置,提出了一种应用于框架结构既能消能又能隔震的新型分离式摩擦滑移隔震系统,探讨了其相应的设计和应用方法。采用MTS电液伺服试验系统,对文中研发的新型摩擦滑移隔震装置进行了摩擦系数测定试验,测试了摩擦滑移隔震装置的静和动力摩擦系数,建立了相应的摩擦滑移恢复力模型。采用SAP2000有限元分析软件,分析了某框架结构在抗震时和滑移隔震时的地震反应规律,从结构的加速度反应和层间位移反应、层间剪力反应等方面分析了隔震结构的减震效果。结果表明,新型摩擦滑移隔震装置的减震效果比较明显。一般情况下当场地类别为Ⅱ类,抗震设防烈度为8度时,利用新型滑移隔震结构的加速度反应可降低50%左右,层间位移反应减小明显,层间剪力反应可降低50%左右。另外,只要确定合理的构造以及实施方案,这种装置能够满足框架结构的隔震减震要求,可应用于实际工程结构。  相似文献   

7.
设计制作了基础隔震软碰撞限位实验模型与3种类型的钢螺旋弹簧限位器,给出了实测的限位器力学特性参数。进行9种工况的振动台模型实验,分析实验数据得出了软碰撞限位器参数对结构反应的影响规律,优选出了适用于本隔震实验模型的软碰撞限位工况。  相似文献   

8.
变刚度隔震保护装置试验研究   总被引:1,自引:1,他引:0  
通过在距离隔震层一定位移处设置由弹簧和与其串联的限位挡板组成的变刚度保护装置作为第二道防线,成功地进行了五层框架的变刚度隔震保护模拟地震振动台试验。理论分析和试验结果表明,变刚度隔震保护装置能有效改变结构动力特性,减小隔震层的变形,使之限制在允许的范围内。  相似文献   

9.
以总输入能量、综合耗能比和隔震层最大位移为响应指标,以能量法为基础,采用正交试验的方法,计算并分析了村镇建筑在地震作用下的响应指标对系统参数的敏感性,探讨了系统参数对响应指标的影响趋势。研究表明:系统参数对总输入能量的影响与场地类别关系不大,但对综合耗能比和隔震层最大位移的影响与场地类别关系较大,Ⅳ类场地条件下的综合耗能比和隔震层最大位移要远远大于其在Ⅱ类和Ⅲ类场地条件下的值,最后,对村镇带限位装置的滑移隔震系统的系统参数给出了建议的取值。  相似文献   

10.
为研究不同构造的土坯结构玻璃珠-石墨基础滑移隔震体系的受力性能,进行了5个不同构造的玻璃珠-石墨基础滑移隔震土坯墙试件的低周反复荷载下受力性能试验。试件1墙体为370mm土坯墙,试件2墙体为土坯墙夹砌粉煤灰砌块承重节能一体化370mm墙体,试件3墙体为在试件2墙体基础上加设交叉钢筋的墙体,试件4墙体为在试件2墙体基础上内置钢丝网的墙体,试件5墙体为在试件2墙体两端用再生砖代替土坯砌筑的墙体。基于试验,分析了各试件基础滑移隔震性能,研究了不同构造土坯墙的承载力、延性、滞回特性和破坏特征。研究表明:玻璃珠-石墨基础滑移隔震层隔震性能稳定;滑移隔震层上下基础梁限位孔及其限位钢筋装置可有效控制基础滑移限值;相同墙厚的土坯夹砌粉煤灰砌块墙和土坯墙抗震性能接近;加设交叉钢筋的墙体抗剪承载力明显提高;内置钢丝网的墙体整体性好,抗震耗能能力显著提高;墙体端部用再生砖代替土坯砌筑后,由于再生砖强度高于土坯,提高了墙体边缘约束性能,抗震性能明显提高。玻璃珠-石墨基础滑移隔震土坯结构可用于单层土坯农房结构隔震设计。  相似文献   

11.
The seismic response of light secondary systems in a building is dependent on the response of the primary structural system to the seismic ground motion with the result that very high accelerations can be induced in such secondary systems. This response can be reduced through the use of aseismic base isolation which is a design strategy whereby the entire building can be decoupled from the damaging horizontal components of seismic ground motion by the use of some form of isolation system. The paper presents a theoretical analysis of the response of light equipment in isolated structures and a parallel experimental programme both of which show that the use of base isolation can not only attenuate the response of the primary structural system but also reduce the response of secondary systems. Thus, the design of equipment and piping in a base-isolated building is very much simpler than that for a conventionally founded structure: inelastic response and equipment-structure interaction need not be considered and multiple support response analysis is rendered unnecessary. Although an isolation system with linear elastic bearings can reduce the acceleration of the structure, it may be accompanied by large relative displacements between the structure and the ground. A system using lead-rubber hysteretic bearings, having a force-displacement relation which is approximately a bilinear loop, can reduce these displacements. A parallel experimental programme was carried out to investigate the response of light equipment in structures isolated using lead-rubber bearings. The experimental results show that these bearings can dissipate energy and limit the displacement and acceleration of the structure but are less effective in reducing the accelerations in the internal equipment. The results of both the analysis and the tests show that base isolation is a very effective method for the seismic protection of light equipment items in buildings.  相似文献   

12.
多层建筑隔震改造设计   总被引:9,自引:0,他引:9  
本文介绍了某多层建筑隔震改造的初步设计,采用隔振技术来进行抗震加固改造,上部结构的地震作用可降低,上部结构不需加固即可正常使用;且楼面的加速度反应减小,可以保护内部的仪器设施在地震时不受破坏。该建筑的平面呈L形,其扭转影响较大。考虑到抗风和扭转作用,在边远处选用铅芯叠层橡胶支座。建筑物的隔震改造具有明显的经济效益和社会效益,是今后发展的方向。  相似文献   

13.
Base isolation can be used both to protect the structure and simultaneously to reduce the response of internal equipment. The seismic response of a base-isolated structure has been studied through the shaking table test or numerical calculation before. The object of this paper is to analyse a base-isolated structure by a different analytical approach—perturbation analysis. Recognizing that the horizontal stiffness of an isolation system is much smaller than that of the superstructure, the mathematical expressions of the modal properties of base-isolated structures are derived by the perturbation method in terms of the modal properties of the superstructure and used to study the dynamic response of superstructure and attached equipment in the base-isolated building. This study shows that the first base-isolated mode not only controls the superstructural response but also dominates the response of high-frequency attachment. The contribution of higher modes to the response of base-isolated structures, which is proportional to the horizontal stiffness of isolation system, is very small.  相似文献   

14.
基于抽样调查的安徽农村民居震害预测与减灾对策周安   总被引:2,自引:0,他引:2  
周安  孙洁  杨勇 《地震学报》2009,31(1):100-107
在安徽省的皖北、皖中和皖南地区,分别抽样4个乡镇总计781户农村民居,进行抗震性能调查,得出安徽省农村住宅在建筑年代、结构形式、建筑材料、地基基础及构造连接等方面的统计数据.在此基础上,运用建筑物地震易损性的概率分析法,对所调查的民居进行震害预测.分析表明,安徽农村民居在基本设防烈度地震作用下,尚不会发生毁灭性破坏,但中等破坏将较大面积发生.提出了农村民居防震减灾的政府管理和技术措施等对策.经济分析认为,增加约3%——4%建房投资,即可基本实现国务院的防震减灾目标.   相似文献   

15.
Base isolation is a well known technology that has been proven to reduce structural response to horizontal ground accelerations. However, vertical response still remains a topic of concern for base‐isolated buildings, perhaps more so than in fixed‐base buildings as isolation is often used when high performance is required. To investigate the effects of vertical response on building contents and nonstructural components, a series of full‐scale shaking table tests were conducted at the E‐Defense facility in Japan. A four‐story base‐isolated reinforced concrete building was outfitted as a medical facility with a wide variety of contents, and the behavior of the contents was observed. The rubber base isolation system was found to significantly amplify vertical accelerations in some cases. However, the damage caused by the vertical ground motions was not detrimental when peak vertical floor accelerations remained below 2 g with three exceptions: (1) small items placed on shelves slid or toppled; (2) objects jumped when placed on nonrigid furniture, which tended to increase the response; and (3) equipment with vertical eccentricities rocked and jumped. In these tests, all equipment and nonstructural components remained functional after shaking. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

16.
偏心隔震结构在地震动作用下,除发生平动外,还将发生平-扭耦联的反应,从而使震害加重,尤其是隔震层较易发生破坏。本文利用自行编制的分析程序,对偏心多塔隔震结构进行了数值分析,在此基础上,提出偏心多塔结构同基础隔震的设计方案。数值模拟计算结果表明,对偏心单塔隔震结构,在地震作用下采用多塔同基础隔震的方案,能大幅度降低结构隔震层的扭转反应,其中最大扭转加速度最少降低55%,最大扭转角最少降低84%。可见,在条件许可时,将相邻偏心单塔结构采用同基础隔震的方案,对提高隔震效果是有利的。  相似文献   

17.
多向地震作用下隔震配电建筑物的非线性动力反应分析   总被引:1,自引:0,他引:1  
本文结合我国首例将隔震技术应用于变电建筑物的工程———西安市330kV西北郊变电站110kV配电楼工程,研究隔震结构在多向地震作用下的非线性动力反应,并把计算结果与单向地震作用的结果进行分析比较。结果表明,本工程采用隔震技术是可行的,采用基础隔震措施可有效地控制结构的偏心扭转效应,使屋面层及楼面层的运动规律趋于一致,建筑物整体趋于平动,同时还可显著降低上部结构及电气设备的地震作用,并且在多向地震作用下的结果比单向地震作用时的隔震效果更加合理。目前该工程已竣工投产,本文工作将为隔震技术在电力系统的更广泛应用打下一个良好的基础。  相似文献   

18.
从克拉玛依市通讯新村12号住宅楼所处的自然环境条件、风振测试、楼房风荷载计算等方面,分析了12号楼房动力特性、楼房风振影响程度以及引起楼房风振原因。造成克拉玛依市通讯新村12号楼风振的原因是,该楼楼房基础互不相连,整体性差,而且楼房楼层高,基础浅,抗风能力差;其次是结构突出的0.5 m纵墙外挑墙垛,增强了风振响应。对该楼房采取减振措施后取得显著的减振效果,减振率达82%。  相似文献   

19.
A building with a seismic isolation system, in an earthquake, is recognized as producing substantially smaller accelerations and deformations compared with a building that use other systems. This type of system is therefore expected to better protect the building's nonstructural components, equipment, and other contents that are essential for the activities conducted in the building. Unlike many available studies on building responses, only a small number of studies on a buildings' nonstructural component responses are available, and no study has directly addressed building performance with regard to nonstructural component protection. This paper therefore measures the performance of various seismically isolated buildings. Specifically, the effects of important structural parameters, namely, isolation stiffness, isolation damping ratio, and number of stories on the response of base‐isolated structures are investigated parametrically. Ground motions with 2% exceedence in 50years Maximum Considered Earthquake (MCE) are used. Performance is compared with that of fixed‐base structures in order to present data that will be useful in justifying the more costly technology. The buildings are 3, 9, and 20 stories, represented by MDOF shear‐beam models. As examples of displacement‐sensitive and acceleration‐sensitive components, partition walls and ceilings are considered, respectively. The Pacific Earthquake Engineering Research Center performance‐based earthquake engineering methodology is adopted to evaluate the failure return periods of the examples based on their available fragility curves. In addition, the curves are varied hypothetically to understand the sensitivity of the return period to the curve features. Then, the median and dispersion of fragility curves required to satisfy the components' desired failure return period are obtained. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

20.
基于抑制升船结构顶部厂房地震鞭梢效应的目的,本文提出了升船结构顶部厂房屋盖MR智能隔震模糊控制的思想。文中,在建立屋盖智能隔震升船结构计算力学模型的基础上,建立了屋盖MR智能隔震系统对升船结构顶部厂房地震反应模糊控制的设计计算方法。文中并以中国某大坝巨型升船结构为背景,设计了屋盖MR智能隔震系统对升船结构顶部厂房地震反应模糊控制的控制系统。仿真分析和对MR阻尼器的参数研究表明,安装合适的屋盖MR智能隔震系统并采用模糊控制策略能有效地抑制具有不确定参数升船结构顶部厂房地震反应的鞭梢效应,且模糊控制器能保持较好的稳定性能。  相似文献   

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