共查询到19条相似文献,搜索用时 125 毫秒
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文章选取一栋钢筋混凝土框架医院建筑为研究对象,采用叠层分析法对该建筑进行隔震-减震混合控制的设计。选取7条地震波,采用Perform-3D软件分别在设防地震和罕遇地震下对隔震结构和隔震-减震结构进行动力时程分析,对比其抗震性能的差异。结果表明,在设防地震和罕遇地震下,相较于隔震结构,隔震-减震结构能有效减小结构的层间位移角和顶点位移,提高结构的抗震性能水准。 相似文献
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运用ANSYS大型有限元软件对巨型框架结构进行三维建模,同时根据用钢筋混凝土斜撑框架结构体系代替框架-剪力墙结构体系的思路,提出了一种巨型框架-次框桁架结构新体系,建立了巨型框架-次框桁架结构有限元模型。对两种结构进行了模态分析和动力时程响应分析,同时进行了抗震性能的对比。计算结果表明,巨型框架—次框桁架结构这一新型体系是有可行性的,为以后巨型结构的研究发展提供了一种新的思路。 相似文献
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采用ANSYS有限元程序对巨型框架结构进行了抗震动力时程分析,讨论了巨型框架结构在多条地震波作用下的动力位移及内力等地震响应。计算结果表明,在几条不同的地震波作用下,巨型框架结构的主、次结构的地震反应是有差异的,就所讨论的巨型框架结构,El-centro地震波对结构的地震影响是最明显的;次框架的地震反应比主框架强烈,在结构抗震设计中不能忽略次框架的抗震问题。计算结果对巨型框架结构的抗震设计有较大的参考价值。 相似文献
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采用ANSYS通用有限元程序建立了巨型框架结构隔震分析的动力计算模型,对巨型框架结构进行了隔震动力时程计算,给出了巨型框架结构隔震后在多条地震波作用下的动力位移及内力等地震响应。计算结果表明,巨型框架结构在隔震后具有良好的抗震性能,可有效地降低结构的地震响应,计算结果对于确保巨型框架结构的抗震安全性具有较大的意义,同时对选择结构构件截面尺寸,也具有较大的参考价值。 相似文献
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在含减振子结构的巨型框架结构(MFVCS)中,通过在部分主、次框架的连接处,即次框架柱底部和主框架梁之间设置隔震支座,从而形成减振子结构。为研究MFVCS的减震效果,设计并制作了一个几何缩尺比为1/25的模型,通过更换最顶部的子结构柱底的支座类型,形成非减振和单减振巨型框架两个结构。通过振动台试验,得到了两结构的动力特性和加速度、位移响应,并对比分析了不同地震动作用下的减震效果。结果表明:试验过程中主体结构损伤轻微;不同地震波作用下加速度和位移峰值减震系数平均值分别为15.1%和12.3%,加速度和位移均方根减震系数平均值均为22.2%;含减振子结构的巨型框架结构具有较明显的减震效果。 相似文献
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隔震技术是提高既有RC框剪结构抗震性能的重要手段,屈重比是隔震设计时的关键参数,但其对该类隔震加固结构的影响规律研究相对较少.针对这一问题,本文选取两栋不同高度的既有RC框架-剪力墙作为原型结构,以屈重比为变量各设计了 6个分析案例,重点分析了其对该类隔震加固上部结构关键响应(楼面最大绝对加速度和层间位移角)和结构重要设计指标(减震系数、大震隔震层位移)的影响规律.本文案例分析结果表明:屈重比增加1%,楼面最大绝对加速度提高约18%~30%,而层间位移角仅提高约6%~10%;中震减震系数和大震隔震层位移分别决定了传统隔震加固设计时屈重比的上限和下限,建议屈重比取值为1.5%~4%,但当面向韧性目标采用隔震加固时,建议屈重比取值应小于3%,才可有效控制楼面绝对加速度.本研究的相关成果可为既有RC框剪结构传统隔震加固设计以及韧性提升提供参考. 相似文献
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双段消能摇摆结构体系是通过两段串联的摇摆结构,控制主体结构各楼层在地震作用下均匀变形,抑制薄弱层的产生,也降低了主体结构对于摇摆结构的刚度需求。在变形集中的摇摆结构底部布设位移型阻尼器,可进一步提高结构的抗震性能。但是该体系存在承载力较低、上段结构地震反应相对较大的不足。基于此,提出了消能摇摆高位隔震结构体系,即在双段消能摇摆结构体系的分段楼层位置增设劲性支撑,以抑制上段结构的摇摆运动,提高结构的刚度与承载力;同时,下段结构允许发生摇摆,发挥高位隔震层的作用。以消能摇摆高位隔震结构体系为研究对象,分析对比了其他三种结构体系:传统支撑框架结构体系、双段消能摇摆结构体系、不含位移型阻尼器的摇摆高位隔震结构体系。采用OpenSees软件建立了弹塑性有限元分析模型,对四种结构体系进行弹塑性抗震分析和增量动力时程分析。研究表明,消能摇摆高位隔震结构体系的刚度与承载力较高,地震反应较小,抗震性能与抗倒塌性能良好。在摇摆结构分段位置加设劲性支撑层,可以抑制上段结构在地震作用下的变形,并发挥下段摇摆结构的隔震作用。布设于分段位置与摇摆结构底部的阻尼器,可以充分消耗地震能量,提高结构体系的抗震性能。 相似文献
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Seismic isolation is a well‐known trend in earthquake design of structures. It enables a reduction in structural response to earthquakes and minimizes possible damage to buildings. This paper deals with a new constructive solution for seismic isolation, adapted to a structural scheme traditionally used in the Mediterranean region; it is usually presented as an open ground floor with a system of reinforced‐concrete columns, supported on single bases. The best‐known base isolation systems, implemented in existing structures, are elastomeric bearings and friction pendulums. The proposed solution is based on the idea of pendulum suspension brackets installed in seismic isolation columns. The main differences between existing solutions and the proposed one are that the latter requires no additional space for its installation, its lifetime corresponds to that of the structure, and no service is required during the entire period. The proposed solution provides additional damping and, like other base isolation systems, shifts the vibration period of the structure, reducing its spectral response. Since its size is compact, the ground‐floor columns of existing structures with low seismic capacity may easily be replaced by the proposed ones. It yields significant improvement in structural seismic response. Numerical simulation shows that buildings where the proposed system is installed are likely to sustain minimal damage, or none at all, whereas traditionally designed ones may suffer major damage or even collapse due to the same earthquake. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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基于ANSYS的LRB性能模拟验证分析 总被引:1,自引:0,他引:1
铅芯橡胶支座(LRB)是一种有效的隔震装置,它通过延长结构的周期、增加结构的阻尼来减小结构的地震反应.在结构隔震分析中,LRB扮演了一个很重要的角色,对其模拟程度的正确与否对整个结构的分析结果将产生很大影响.本文采用大型通用有限元程序ANSYS,对一个单自由度隔震体系进行了LRB性能模拟验证分析,分析表明:在合理确定输入地震动PGA临界点的前提下,采用ANSYS中的Combin40单元来模拟LRB的滞回性能,能获得较为满意的效果;同时通过与SAP2K时程分析比较,也验证了ANSYS分析结构隔震的可靠性. 相似文献
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多层框架隔震结构的地震扭转反应分析 总被引:12,自引:2,他引:10
本文分析了多层框架基础隔震结构单轴偏心的地震扭转反应 ,建立了地震作用下多层框架隔震结构扭转反应的运动方程 ,在隔震和非隔震情况下 ,计算了结构模型不同偏心的地震反应。结果表明 ,对存在扭转变形的结构来说 ,采用基础隔震可明显减少结构的扭转反应 相似文献
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A seismic structure isolated by a conventional passive isolation system is usually a long-period structural system; therefore, although its dynamic response may be effectively mitigated in a regular earthquake, the responses may be considerably amplified in a near-fault earthquake with long-period characteristics, due to the low-frequency resonant effect. In order to overcome this problem, a sliding isolation system equipped with a new type of the semi-active damper called a resettable variable stiffness damper (RVSD) is proposed in this study. An RVSD damper is similar to a conventional resettable stiffness damper, except that it has a variable stiffness part. By controlling the variable stiffness, the damper force provided by the RVSD will follow a target force that is determined on-line by a general, active control law. As a result, the RVSD damper is able to prevent the abrupt changes of the damper force that inevitably exists in a conventional resettable damper. The harmonic and seismic responses of an isolation system with the RVSD are studied numerically and compared with the other types of isolation systems. The simulated results demonstrate that the RVSD is able to attenuate the low-frequency resonance behavior of the seismic isolation system induced by long-period ground motions. As compared with an isolation system with a conventional resettable damper, the study shows that isolation with the RVSD is superior in reducing the acceleration response due to a near-fault earthquake, while maintaining its effectiveness in the suppression of the isolator displacement. 相似文献
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Seismic isolation is increasingly being used in both traditional and industrial structures for its ability to reduce structural responses while effectively protecting systems and components, such as machinery. After applying isolation, the standardize design can be achieved during seismic design of nuclear power plant. However, the seismic response of nuclear structure with different isolation characteristic parameters under different ground motions has not been fully studied. In this paper, a new generation passive nuclear power plant model was simulated with finite element method. The acceleration response, deformation, seismic mitigation efficiency, and response discreteness of nuclear structures with different isolation characteristic parameters were analyzed. The effect degree of isolation characteristic parameters on seismic response of nuclear structures was investigated. Performance spaces are introduced as an alternate method for evaluating responses of nuclear structures. The results show that isolation systems largely reduce both the mean value and discreteness of seismic response of nuclear structures. 相似文献