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1.
为研究不同场地类型隔震支座主要参数(等效水平刚度Kf、屈服前刚度K1和屈服力Qd)对基础隔震结构双向地震响应的影响,设计Kf、K1或Qd不同的18栋基础隔震结构,基于SAP2000软件,对各隔震结构分别在不同场地类型的4组地震动作用下的双向地震响应进行分析。结果表明,隔震支座参数对不同场地类型的基础隔震结构在双向地震作用下的加速度最大值和基底剪力最大值均有显著影响,但其对基础隔震结构隔震层位移最大值的影响需根据场地类型具体考虑;在Ⅰ、Ⅱ、Ⅲ类场地上,随着Kf、K1和Qd增大,基础隔震结构的加速度最大值和基底剪力最大值均呈明显的上升趋势,但对隔震层位移最大值的变化影响较小;在Ⅳ类场地上,不同隔震支座参数对隔震层位移最大值的影响较大,且有明显的规律性,即随着Kf、K1、Qd的增大,隔震层的位移峰值迅速减小,最大减幅达80%以上。  相似文献   

2.
提出一种新型双层滚轴隔震支座.运用有限元软件ANSYS中已有的单元进行组合.采用双线形非线性弹簧模拟双层滚轴隔震支座模型,并以某4层混凝土框架结构为例,建立层间剪切模型进行时程分析,研究双层滚轴隔震支座的隔震效果,研究结果表明该双层滚轴隔震支座能有效地解决建筑结构的基础隔震问题。  相似文献   

3.
针对基础隔震局限于减小地震波高频成分对结构影响的缺点,将磁流变(MR)阻尼器与滚动隔震支座相结合形成MR智能基础隔震系统并应用到结构控制中.基于MR阻尼器的Sigmoid模型,进行模糊半主动控制策略设计.在不同种类不同强度的地震波作用下,对智能基础隔震控制下2层钢框架结构的反应进行了仿真分析.结果表明,MR智能基础隔震...  相似文献   

4.
基于系统的振动微分方程,用数值方法求得隔震结构的加速度反应衰减比。采用Ansys7.1程序中已有的单元,通过结构实例分析,计算采用传统抗震结构和隔震结构的加速度反应衰减比,说明合理选取隔震结构的刚度和阻尼的重要性,为隔震结构工程设计提供了合理方法和理论依据。  相似文献   

5.
叠层橡胶支座隔震结构的原型测试结果分析   总被引:1,自引:0,他引:1  
对一个带有叠层橡胶支座隔震结构的原型减震台进行不同位置自然地震波的观测,根据减震台的结构设置建立了一个地基-结构动力相互作用的计算模型,然后输入观测到的自然地震加速度波形,计算减震台台面的地震响应,并把计算结果与观测结果进行比较分析,计算结果与试验结果吻合程度较好,从而验证出此计算模型有很高的可靠度。  相似文献   

6.
针对超设计基准地震作用下隔震层存在过大变形、影响结构安全等问题,基于已提出的一种隔震支座沿曲面布置的隔震结构,通过变形和受力分析建立了简化双自由度动力模型,得到了系统关键动力参数,即公转频率、自转频率及单摆频率等的计算式.进一步给出了结构响应传递函数,明确了结构高宽比、曲面角度、隔震层阻尼比对结构响应的影响规律,并基于...  相似文献   

7.
对厦门某一幼儿园教学楼进行基础隔震设计,采用动力时程分析方法,分析结构在设防烈度下中震及大震作用下的结构响应。对比抗震结构和隔震结构两者的周期、层间剪力和层间位移,对比结果表明,相较于抗震结构,隔震结构的周期变长,隔震结构受到的地震作用效应大幅降低,上部结构的水平向减震系数为0.39。经设计验算,结构隔震设计满足我国现行建筑抗震设计规范的规定,可为类似基础隔震工程的应用提供借鉴。  相似文献   

8.
针对铅芯橡胶隔震支座在长周期长持时地震作用下由于铅芯温度上升发生力学性能退化的问题,通过压剪设备对铅芯橡胶隔震支座进行了快速水平往复力学性能试验,研究其在快速往复加载下水平剪切力学性能的变化。试验结果表明,铅芯橡胶隔震支座在快速往复荷载作用下,随着加载次数的增多,其特征强度显著下降,且前期下降的幅度比后期大,屈服后刚度在加载过程中变化较为平缓。然后基于试验结果,采用改良的广义Bouc-Wen模型,提出了铅芯橡胶隔震支座在快速水平荷载下力学性能退化的力学模型,然后基于铅芯橡胶隔震支座性能退化的力学模型,对一实际隔震结构进行仿真,研究该结构在长周期长持时地震作用下的动力响应。仿真结果表明考虑支座退化效应得到的隔震层位移和层间位移角不仅比不考虑支座退化效应得到的大,且最大值已超出设计允许范围,因此在基础隔震设计时建议要考虑铅芯橡胶隔震支座在长周期长持时地震作用下力学性能退化情况。  相似文献   

9.
提出了一种基于主动控制算法优选双线性并联基础隔震体系隔震层参数的方法。该方法是把并联基础隔震体系隔震层替换为主动控制作动器和只具有纯刚度的橡胶垫,利用主动控制算法——线性二次型经典最优控制算法计算主动最优控制力,求出受控结构隔震层处的层间刚度和层间阻尼比;并使并联基础隔震体系隔震层的等效刚度和等效阻尼比在数值上与之对应相等,利用双线性滞回曲线模型即可推导出隔震层的2个参数(回复刚度和屈服剪力系数)。为了验证该方法,对一工程实例进行了仿真分析,结果表明,该方法是可行的。  相似文献   

10.
针对橡胶隔震垫作为一种被动控制装置,存在最优控制范围窄的局限性。将磁流变阻尼器与橡胶隔震垫相结合,组成智能基础隔震系统应用于结构振动控制中,数值模拟分析了在地震力作用下原结构,普通隔震结构,隔震层附加MR阻尼器在Passive—off状态,Passive—on状态和磁流变阻尼器半主动智能状态下结构的反应。试验结果表明,结构在磁流变阻尼器半主动智能状态下控制效果最优,能有效克服被动隔震最优控制频带窄的缺点,其相对一般被动隔震装置,能同时减小隔震层位移,上部结构层间位移和各层最大加速度。  相似文献   

11.
模块化建筑具有整体装配率高,施工绿色环保、高效等优点,然而其抗震性能相对较差,震后修复成本高。将隔震技术应用到模块化建筑中,可在不改动上部结构的前提下,改善其整体抗震能力。相比传统橡胶隔震技术,摩擦摆隔震技术具有承载力大、工业化程度高、湿作业少等优势。为此,研发了一种自适应变摩擦摆隔震支座,分析了该支座力学特性,确定其有限元模拟方法。对变摩擦摆隔震支座进行不同工况下剪切性能试验,试验和有限元模拟结果相对误差均在10%以内,验证了有限元模拟方法的正确性。基于GB/T 51408—2021《建筑隔震设计标准》提出模块化钢框架变摩擦摆隔震结构一体化直接设计方法,以实际工程为背景,设计模块化钢框架摩擦摆和变摩擦摆隔震结构,并对非隔震结构和隔震结构的抗震性能进行对比分析。研究表明:相比摩擦摆隔震支座,所提出变摩擦方式可实现支座等效刚度增加11%左右,等效阻尼比增加18%左右;相比摩擦摆支座隔震结构,变摩擦摆支座隔震结构的楼板加速度、层间位移角、层间剪力和上部结构损伤程度略有增加,但隔震层位移明显减小,且这种特性随地震动强度的增加而愈明显,体现了变摩擦摆支座的自适应性。  相似文献   

12.
Generally, when a prototype is scaled down to a scale model, all parameters of the scale model should be designed to satisfy the similitude criteria. For a base‐isolated structure with rubber bearings, however, it is technically difficult to obtain small‐sized rubber bearings with the first shape factor satisfying the similitude criteria. This distortion affects the similitude ratio of the vertical stiffness of the bearings and, thus, influences the similitude ratio of the horizontal response of the structure because of the overturning effect. To solve this problem, a coordinative similitude method is proposed for scale model testing of structures with rubber bearings by adjusting configuration of the isolators to match the similitude ratio of the overturning stiffness of the isolation layer. A full‐scale and two 1/3 scaled bearings were designed and tested, and their similitude relations were evaluated. Test results of the model bearings were extrapolated to the OpenSEES model of a conventional model building and a coordinative building designed based on the conventional similitude method and the coordinative similitude method, respectively. A comparison between seismic responses of two model buildings against the prototype building indicates that the coordinative similitude method has significantly larger accuracy than the traditional similitude method.  相似文献   

13.
The development and applications of a semi‐active friction damping system with amplifying braces is studied. A system of dampers and braces, defined as the friction damping system with amplifying braces (FDSAB) is considered. Active control theory with velocity and acceleration feedback is used to obtain the control forces in the proposed system. The system can be used efficiently to enhance the damping of a structure and improving its response. The efficiency of the proposed system is demonstrated by the numerical simulation of a seven storey building subjected to earthquakes. The simulation shows that the behaviour of the damped structure with the FDSAB is significantly improved. The required control forces are much less compared with a control system with semi‐active friction dampers connected either to chevron or diagonal braces. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

14.
This paper investigates effectiveness of selective control strategy in hybrid base isolation systems including isolators and semi‐active variable friction (VF) dampers. According the selective control strategy, VF dampers are activated just if the displacement at the isolators exceeds the threshold value. The slip‐force control is based on the values of floors' accelerations and velocities. By controlling the slip‐force magnitude in the VF dampers, effective energy dissipation can be achieved in a seismic event. Activation of dampers according to the selective control strategy allows high‐energy dissipation by minimum energy required for adjusting the slip‐force. Performance of a multi‐storey frame with a base isolation system and VF dampers under various earthquake records was obtained numerically using originally developed MATLAB routines. Seismic response of the analysed structure with the selective controlled system was compared with that when the VF dampers were active during the whole earthquake. It is shown that adjustment of the slip‐force in a selective manner allows additional reductions in peak displacements and accelerations of the structure. The results also demonstrate that this control strategy yields reduction of the base displacement without increasing the peak base shear forces. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

15.
孙柏锋  潘文 《山西建筑》2008,34(7):9-10
针对多层隔震结构提出了两阶段设计法的概念,以四层多层框架结构体系为例进行了分析,结果显示该设计方法具有简便、符合工程应用的特点,且有利于提高设计质量,减少设计周期。  相似文献   

16.
The active tuned mass damper (ATMD) is a reliable energy-dissipating device to effectively protect structures from serious damages due to earthquake excitations. This study proposes the optimal design of sliding sector control (SSC) for the seismic protection of an 11-story shear building structure equipped with ATMD. First, the SSC controller is optimally designed for the seismic control of the structure subjected to an artificial earthquake. Then, the effectiveness of the optimized SSC (OSSC) is assessed in reducing the seismic responses of the structure subjected to four near- and far-fault earthquake excitations. The efficient performance of the OSSC technique is also validated and compared with that of a number of the control techniques such as linear quadratic regulator (LQR), fuzzy logic control (FLC), proportional-integral-derivative (PID), and optimal sliding mode control (OSMC). Comparative results demonstrate the efficiency and robustness of the proposed OSSC in comparison with those of the other controllers.  相似文献   

17.
In this paper, an application of the hybrid intelligent control algorithm to semi‐active control of the magnetorheological (MR) damper is presented for engineering structures. The control signal is optimized directly by the µGA approach to obtain the numerical relation between the control signal and the system output. This relation is then stored in the weight value of a trained artificial neural network, which can be available for another structure subjected to other seismic inputs. The results of a numerical example indicate that the semi‐active control of the MR damper based on the hybrid algorithm can efficiently reduce the structural responses induced by an earthquake. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

18.
多滑面摩擦隔震支座具有刚度和阻尼的自适应性,在基于性能的桥梁抗震设计中有广泛的应用前景。本文以某近海连续梁桥为工程背景,考虑海洋软土条件,应用p-y法模拟桩-土相互作用,通过单摩擦摆(FPS)串联组成多滑动面摩擦摆支座(MFPS)模型,并建立全桥有限元模型。采用反应谱法和快速非线性分析(FNA)两种方法,对设置单滑面摩擦摆支座和多滑面摩擦摆支座的两种不同支座的隔震桥梁体系进行地震响应分析。对比分析两种方法得到的两种隔震桥梁结构的支座滞回性能和墩底剪力等的地震响应规律。研究结果表明,两种支座均具有较好的隔震效果,采用MFPS支座的桥墩的地震响应比FPS支座有所减小,且具有较大位移能力。  相似文献   

19.
A feedback control system usually implements active and semi‐active control of seismically excited structures. The objective of the control system is described by a performance index, including weighting matrix norms. The choice of weighting matrices is usually based on engineering experience. A new procedure for weighting matrix components choice based on the parametric optimization method is developed in this study. It represents a two‐step optimization process. In the first step a discrete‐time control system is synthesized according to a quadratic performance index. In the second step the weighting coefficients are obtained using the results of the first step. Numerical simulation of a typical structure subjected to earthquakes is carried out in order to demonstrate the effectiveness of the proposed method. It shows that applying the proposed technique provides a choice of the weighting matrices and results in enhanced structural behaviour under different earthquakes. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

20.
隔震结构由于其优越的抵御地震能力而在实际建筑工程中得到了广泛的应用。针对建筑隔震结构,我国GB 50011—2010 《建筑抗震设计规范》所推荐的水平向减震系数法,通过引入水平向减震系数修正未采取隔震措施结构的反应谱法结果,间接获得采取隔震措施后结构的地震响应。该法具有较强的操作性,但其合理性一直受到工程界的关注。针对隔震结构的局部非线性行为,建立隔震结构地震响应的时域显式表达式,利用其降维列式优势实现隔震装置局部非线性自由度的高效降维迭代计算。结合随机模拟方法,统计获得非线性隔震结构在地震作用下的层间剪力。在此基础上,针对等效线性隔震结构反应谱法得到的层间剪力进行校准,获得各楼层层间剪力校准系数,然后采用该系数调整反应谱法计算得到的等效线性隔震结构各楼层的构件内力。采用所提出的层间剪力校准系数法和规范推荐的水平向减震系数法,对两个基础隔震结构进行地震作用效应分析,结果表明所提出方法能有效提高隔震结构地震响应的计算精度。  相似文献   

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