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大底盘多塔楼结构的混合隔震控制 总被引:2,自引:0,他引:2
结合某实际工程,针对大底盘多塔楼结构提出混合隔震的控制策略,即对大底盘上的一栋或多栋塔楼采用隔震技术,并在隔震层附设一定数量的被动、主动或半主动的减震控制装置。建立了这种大底盘多塔楼结构混合隔震控制体系的运动方程,方程中各塔楼与下部结构及隔震层之间的刚度解耦,并考虑了隔震层的非线性。研究中比较了被动非线性粘滞阻尼器,半主动变孔隙阻尼器与理想主动控制时的减震控制效果。结果表明,这种混合隔震体系可以有效地减小上部塔楼与下部结构的地震反应,提高大底盘多塔楼结构的抗震安全性,取得明显的经济和社会效益。半主动变孔隙阻尼器可以极好地追踪理想主动控制力,取得与理想主动控制相近的减震控制效果。被动非线性粘滞阻尼器也能取得较好的减震效果,且易于维护,经济性较好,从工程应用的角度来看更为现实可行,具有较好的应用推广价值。 相似文献
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多自由度主动变刚度控制体系的振型控制 总被引:7,自引:1,他引:6
本文利用振型变换技术,将设置了m个控制器的b自由度主动变刚度控制体系降阶为1个自由度的主动变刚度控制体系,进而提出了振型控制律-包括第一振型控制律和主振型控制律,仿真分析结果表明,第一振型控制律可以有效地控制受控结构的相对位移反应,主振型控制律则可以有效地控制受控结构的相对位移反应和层间位移反应。 相似文献
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为解决斜拉桥横向塔-梁、墩-梁固结体系导致地震响应过大的问题,兼顾斜拉桥横向抗风、隔震需求,基于溢流阀及油阻尼器性能,设计了一种刚度可变的新型油阻尼器,进而提出油阻尼器与滑动球型钢支座、油阻尼器与叠层橡胶支座并用的两种横向减震体系。以某近海双塔双索面斜拉桥为研究对象建立有限元模型,利用时程法计算两种体系减震效果。结果表明:相对于传统的塔-梁固结体系,应用两种减震体系时,塔底弯矩分别降低44. 9%、43. 6%,塔底剪力分别降低40. 7%、39. 0%,且不会引起过大支座位移、残余位移。滑动球型钢支座刚度低,地震响应更小,但缺乏回复机制,支座残余位移稍大;叠层橡胶支座刚度较高,残余位移小,但高刚度使各构件承受更大惯性力,达到相同减震效果需阻尼器提供更高出力。两种塔-梁减震体系各有优劣,但均具有较好的减震效果,均可应用于斜拉桥横向减震。 相似文献
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为完善超长联大跨连续梁桥的减、隔震技术,将负刚度装置引入到超长联大跨隔震连续梁桥中组成新型减、隔震系统,并与黏滞阻尼器-摩擦摆支座组合减震系统进行比较。基于CSiBridge软件建立全桥有限元模型,负刚度装置采用弹性多段线模拟,摩擦摆支座采用双线性恢复力模型,黏滞阻尼器采用Maxwell模型,输入3条地震波进行非线性时程分析,考查两种新型减、隔震系统下桥梁结构的地震反应,探究负刚度系统及黏滞阻尼器系统对超长联大跨连续梁桥地震反应的控制效果。研究结果表明:负刚度装置与黏滞阻尼器均可以有效地减小超长联大跨隔震连续梁桥的支座位移。负刚度装置对桥墩内力反应及梁体加速度反应的控制优于黏滞阻尼器。负刚度装置在超长联大跨连续梁桥地震反应控制中有较好的应用前景。 相似文献
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安装形状记忆合金阻尼器的剪力墙结构抗震性能分析 总被引:1,自引:0,他引:1
为减轻钢筋混凝土剪力墙连梁的地震后永久性损伤,同时保持连梁的耗能机制,本文提出在剪力墙连梁中安装新型形状记忆合金(Shape Memory Alloy,简称SMA)阻尼器,并研究该阻尼器对剪力墙结构地震响应的减震效果。通过一幢12层剪力墙结构地震反应的时程分析,研究了SMA阻尼器的附加刚度比和屈服位移比两项特征参数对结构地震反应控制效果的影响规律。计算分析结果表明,当附加刚度比为0.04~0.05,屈服位移比为0.4~0.5时,可以获得较好的减震效果。 相似文献
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介绍了一种具有自主知识产权的新型开关控制型半主动控制系统——主动变刚度.阻尼(AVS.D)系统的减振控制机理,建立了AVS.D结构振动控制体系的运动方程。为了合理补偿AVS.D系统实时控制过程中不可避免地存在着的控制时滞,本文提出一种预测最优控制算法,推导了其开关控制律。为了检验AVS.D系统的减震控制效果及预测最优控制算法的有效性,我们设计研制出AVS.D装置,编制了AVS.D系统预测最优控制的实时控制软件,在某单层钢框架模型上进行了AVS.D系统的模拟地震振动台试验,比较了不同控制方式时的减震效果。研究结果表明,本文所提出的预测最优控制算法是非常有效的,可推广应用于所有开关控制型半主动控制系统。AVS.D系统具有反应放大功能,经济可靠、安全有效,可望有较好的工程应用前景。 相似文献
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两个控制装置的模拟地震振动台试验研究 总被引:2,自引:1,他引:1
本文作者设计制造了一种高效被动阻尼控制(HEDC)装置和一种半主动控制装置-主动变刚度,阻尼(AVS.D)控制装置,并对其控制机理和控制效果进行了模拟地震振动台试验研究,试验结果表明,HEDC控制效果是令人满意的,而AVS.D控制则可以获得更好的效果,尽管它仅需很少的能量输入,试验结果表明,在AVS.D控制中,装置的电磁阀处于开启状态工作的时间较长,即在大部分时间里AVS.D控制系统是通过阻尼而不足刚度来控制受控结构,这在一定程度上降低了控制时滞的影响。 相似文献
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Implementation of efficient vibration control schemes for seismically excited structures is becoming more and more important in recent years. In this study, the influence of different control schemes on the dynamic performance of a frame structure excited by El Centro wave, with an emphasis on reaching law based control strategies, is examined. Reaching law refers to the reachable problem and criteria for the sliding state of a control system. Three reaching laws are designed to present different sliding mode control strategies by incorporating a state space model that describes structural dynamic characteristics of a frame structure. Both intact and damaged structures are studied by using the aforementioned control strategies. The influence of different structural damage extents, control locations and reaching law based control methods are further investigated. The results show that the structure can be well controlled using the sliding mode strategy when the induced structural damage extent does not exceed the standard percentage for considering the structure was damaged, which is 20% reduction in structure stiffness, as reported in the literature. The control effectiveness is more satisfactory if the control location is the same as the direction of external excitation. Furthermore, to study the chattering phenomenon of the sliding mode control method, approximation and detail components extracted from the phase plots of the sliding mode control system are compared via wavelet transform at different scales. The results show that for the same type of control law, the system behaves with similar chattering phenomenon. 相似文献
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结构可变阻尼半主动控制 总被引:12,自引:4,他引:12
本文阐述了结构半主动控制的概念,并介绍了国内外有关结构半主动控制的研究状态,阐述了几种有关结构半主动控制的算法,包括基于经典最优控制的控制律及算法,基于变结构系统理论的滑动模太控制算法和非线性奇次系统的bang-bang控制算法。重点阐述了变结构系统理论和滑移面的确定及控制律的设计。 相似文献
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Recently, sliding‐mode control (SMC) methods have been investigated for application to seismically excited civil engineering structures and have proved to be effective control strategic methods. On the other hand, although another class of well‐known optimal control laws, the so‐called ‘bang–bang’ control, has been investigated for several decades, their potential in civil engineering structural control has not been fully exploited. The purpose of this paper is to present a new control law for civil engineering structures, which is the sliding‐mode bang–bang control (SMBBC). The SMBBC method is a combination of the SMC and the bang–bang control. In consideration of actuators not suitable for high‐speed switching of control forces in the SMBBC in practice, modified sliding‐mode bang–bang control (MSMBBC) law is proposed and demonstrated to be able to provide the same control effects as the SMBBC case. Condition modified sliding‐mode bang–bang control (CMSMBBC) law is also investigated in this paper. In the CMSMBBC case, actuators act only when response quantities exceed some designated threshold values. The determination method of maximum control‐forces for actuators is investigated through example computation. The performance and robustness of the proposed control methods are all demonstrated by numerical simulation. Simulation results demonstrate that the presented methods are viable and an attractive control strategy for application to seismically excited linear structures. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
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地震作用下参数不确定系统的变结构控制 总被引:5,自引:2,他引:3
本文对结构参数具有有确定性的变结构控制系统设计方法进行了研究。首先采用摄动方法给出了结构参数具有确定性的控制系统的运动方程,证明了基于层间剪切模型的参数不确定受控系统与其标称系统具有相同的滑动模态,从而解决了系统切换函数的确定问题,并利用到达条件推导了控制律的表示式。算例分析结果表明,本文的控制方法能有效地减小结构的地震响应,对于结构系统建模存在误差或系统本身存在学确定性的情况,控制效果仍十分显著 相似文献
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基础隔震建筑混合控制的变结构趋近律方法 总被引:2,自引:0,他引:2
本文对叠层胶支座基础震建筑的混合振动控制问题进行了研究。利用控制律设计的变结构趋近律方法,给出了相应的闭环控制律表示式。 相似文献
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Based on the genetic algorithms (GAs), a fuzzy sliding mode control (FSMC) method for the building structure is designed in this research. When a fuzzy logic control method is used for a structural system, it is hard to get proper control rules directly, and to guarantee the stability and robustness of the fuzzy control system. Generally, the fuzzy controller combined with sliding mode control is applied, but there is still no criterion to reach an optimal design of the FSMC. In this paper, therefore, we design a fuzzy sliding mode controller for the building structure control system as an optimization problem and apply the optimal searching algorithms and GAs to find the optimal rules and membership functions of the FSMC. The proposed approach has the merit to determine the optimal structure and the inference rules of fuzzy sliding mode controller simultaneously. It is found that the building structure under the proposed control method could sustain in safety and stability when the system is subjected to external disturbances. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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In this paper, a new system of semi active structural control with active variable stiffness and damping (AVSD) is suggested.
This new system amplifies the structural displacement to dissipate more energy, and in turn, effectively reduces the structural
response in the case of relatively small story drifts, which occur during earthquakes. A predictive instantaneous optimal
control algorithm is established for a SDOF structure equipped with an AVSD system Comparative shaking table tests of a 1/4
scale single story structural model with a full scale control device have been conducted. From the experimental and analytical
results, it is shown that when compared to structures without control or with the active variable stiffness control alone,
the suggested system exhibits higher efficiency in controlling the structural response, requires less energy input, operates
with higher reliability, and can be manufactured at a lower cost and used in a wider range of engineering applications. 相似文献
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多结构混合控制体系研究 总被引:9,自引:0,他引:9
本文提出了多结构混合控制体系的概念及其相应的混合控制装置-常阻尼变刚度控制装置,阐明了其控制原理,建立了两结构混合控制体系的状态方程,其于瞬时最优控制的概念,提出了多结构混合控制体系的控制律,某两结构混合控制体系的仿真分析表明,多结构混合控制体系的概念是正确的,相应的混合控制装置是有效的。 相似文献
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The discrete‐time variable structure control method for seismically excited linear structures with time delay in control is investigated in this paper. The control system with time delay is first discretized and transformed into standard discrete form which contains no time delay in terms of the time delay being integer and non‐integer times of sampling period, respectively. Then the discrete switching surface is determined using ideal quasi‐sliding mode and discrete controller is designed using the discrete approach‐law reaching condition. The deduced controller and switching surface contain not only the current step of state feedback but also linear combination of some former steps of controls. Numerical simulations are illustrated to verify the feasibility and robustness of the proposed control method. Since time‐delay effect is incorporated in the mathematical model for the structural control system throughout the derivation of the proposed algorithm, system performance and dynamic stability are guaranteed. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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Effectiveness of a new semiactive independently variable stiffness (SAIVS) device in reducing seismic response of sliding base isolated buildings is evaluated analytically and experimentally. Through analytical and experimental study of force—displacement behaviour of the SAIVS device, it is shown that the device can vary stiffness continuously and smoothly between minimum and maximum stiffness. Passive sliding base isolation systems reduce interstorey drifts and superstructure accelerations, but with increased base displacements, which is undesirable, under large velocity near fault pulse type earthquakes. It is a common practice to incorporate non‐linear passive dampers into the isolation system to reduce bearing displacements. Incorporation of passive dampers, however, may result in increased superstructure accelerations and drifts; while, properly designed passive dampers can be beneficial. A viable alternative is to use semiactive variable stiffness systems, which can vary the period of the sliding base isolated buildings in real time, to simultaneously reduce bearing displacements and superstructure responses further than the passive systems, which deserves investigation. This study investigates the performance of a 1:5 scaled smart sliding base isolated building model equipped with the SAIVS device analytically and experimentally, under near fault earthquakes, by developing a new moving average non‐linear tangential stiffness control algorithm for control of the SAIVS device. The SAIVS device reduces bearing displacements further than the passive cases, while maintaining isolation level forces and superstructure responses at the same level as the passive minimum stiffness case, indicating the significant potential of the SAIVS system. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献