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1.
本文针对高层建筑风振控制问题,应用基于遗传算法优化模糊规则库的模糊控制方法,通过MR阻尼器实现减小高层建筑风振反应. 采用双输入、单输出的模糊控制策略, 即以风荷载和其变化率为输入量, 以MR阻尼器所提供的控制力为输出量.利用基于遗传算法的优化的模糊规则库,根据作用模糊子集的推理方法进行模糊推理运算, 并采用常用的重心法进行解模糊处理.以某12层框架结构为例, 进行数值模拟分析,并与优化前的模糊控制策略和LQR最优控制策略进行比较.数值分析结果表明,利用遗传算法使优化模糊规则库得以优化,改善了模糊控制的效果,有效地减小了结构的风振反应.  相似文献   

2.
遗传算法的改进及其在应力场反演中的应用   总被引:2,自引:0,他引:2       下载免费PDF全文
利用人工方法产生多样化的初始群体,引入“移民”机制并采用小种群搜索,运用自动调整交换概率与变异概率的方法将遗传算法进行了改进,改进后的遗传算法在防止早熟,提高收敛速度方面有一定改善。最后利用改进的遗传算法反演了青藏高原的应力场,其结果与地质结果有一定的相似性。  相似文献   

3.
模糊神经网络控制系统优化的实整数混合编码遗传算法   总被引:2,自引:1,他引:1  
本文提出了采用实数整数混合编码的遗传算法来优化模糊神经网络控制系统的方法,内容包括:增益、输入和输出变量、控制规则的编码、解码、交叉算子和变异算子以及系统优化的实施步骤。用此方法,可以优化确定系统输入和输出变量的隶属函数以及模糊控制规则,此外,针对框架结构地震反应的主动控制,采用本文方法优化建设了模糊神经网络控制系统,并进行了仿真试验和分析。结果表明,本文方法优化的控制系统具有很好的控制效果,而且优于LQ控制算法。  相似文献   

4.
基于状态反馈的结构鲁棒控制   总被引:8,自引:0,他引:8  
本文采用基于状态反馈的鲁棒控制方法解决地震作用下结构控制问题,首先将结构的运动方程转化为状态方程,利用鲁棒控制方法设计了系统的状态反馈控制律;通过引入控制力权重系数,合理地平衡了控制效果与控制力的关系;对于地震作用下的三层框架模型。仿真验证了该控制方法的有效性,并讨论了各种参数对控制效果的影响。  相似文献   

5.
将混沌遗传算法(Chaos Genetic Algorithm,简称CGA)引入高层结构的风振控制优化中,对采用黏弹性阻尼器来控制风振响应的高层结构进行参数优化;用Matlab语言编制了均布法、迭代法、简单遗传算法(Simple Genetic Algorithm,简称SGA)和混沌遗传算法的风振控制优化分析程序;对9个高层结构进行风振控制优化,对比了算法程序的计算效率以及无控、均布、迭代、SGA和CGA工况下的结构风振响应。研究结果表明:混沌遗传算法可以应用于高层结构风振控制优化之中;混沌遗传算法的计算效率比简单遗传算法最高提升了29%;经混沌遗传算法优化后,黏弹性阻尼器附加给结构的附加阻尼比与均布和迭代相比最高分别提高了61%和22%,CGA工况的顶层加速度响应与均布和迭代法相比最高分别减小了14%和12%。为高层结构风振控制优化研究提供了新思路,具有一定的理论价值和实际意义。  相似文献   

6.
将快速非支配排序遗传算法(NSGA-Ⅱ)和并行遗传算法相结合,提出内嵌NSGA-Ⅱ的粗粒度-主从式并行遗传算法。该算法将种群分为多个子种群,每个子种群可独立并行执行NSGA-Ⅱ操作;达到迁移周期时,子种群之间执行迁移操作;完成迁移后,子种群再次独立并行执行NSGA-Ⅱ操作。以最大层间位移角和最大楼层加速度为目标函数,对14层消能减震钢框架结构上的阻尼器布置位置进行优化分析。结果表明:该算法既实现多目标优化,又提高优化速度;对比常规隔层布置方法,该算法可使结构的层间位移角减震系数和加速度减震系数分别至少提高16.82%和16.01%。  相似文献   

7.
结构地震反应的非全状态控制   总被引:4,自引:2,他引:4  
本文提出了地震下结构芳动控制的一种非全状态控制算法和控制器位置与算法参数统一优化的概念及其统一优化的方法,文中对某试验用模型结构,用红典线最优控制算法和本文提出的控制算法进行了主动控制仿真分析,同时用本文提出的统一优化方法对控制器位置和算法参数进行了优化,结果表明,本文提出的统一优化概念和方法合理可行,控制算法可以取得良好的控制效果。  相似文献   

8.
用遗传算法实现地震信号反褶积   总被引:3,自引:1,他引:3       下载免费PDF全文
遗传算法作为寻优手段具有全局优化和很好的稳定性.本文将遗传算法用于地震信号反褶积处理,与已往方法相比它具有更好的分辨率和稳定性我们采用Bernoulli-Gaussian模型和ARMA模型分别描述地震反射系数序列和地震子波,用最大似然和最小预测误差准则分别构造用于估计反射系数序列和地震子波的目标函数,用遗传算法优化目标函数,以实现地震信号反褶积.  相似文献   

9.
量子遗传算法在大地电磁反演中的应用   总被引:6,自引:5,他引:1       下载免费PDF全文
量子遗传算法(QGA)以量子理论为基础,通过利用量子位编码代替经典遗传算法的二进制位编码,利用量子旋转门定向更新种群来代替传统方法中种群的选择、交叉和变异过程,使得算法具有一定的内在并行运算能力和量子的隧道效应,从而加快了搜索速度,改善了收敛速度,并具有更强的全局寻优能力.本文针对地球物理反演问题的非线性、多极值特点提出一套实现方案,通过理论模型和实测数据试验对比研究,表明量子遗传方法在大地电磁反演中的寻优质量和效果明显优于传统遗传算法.  相似文献   

10.
本文针对建筑结构地震响应半主动控制问题,应用基于遗传算法优化模糊规则库的遗传—模糊控制方法,通过MR阻尼器实现减小建筑结构地震响应。将结构的位移和加速度响应峰值控制双重指标作为目标函数,运用遗传算法的基本操作得到一组优化的模糊推理规则。以结构位移、加速度、地震加速度信号作为输入量,以MR阻尼器所提供的控制力为输出量,分别构造单阻尼器和多阻尼器的模糊控制策略。以某3层和6层框架结构为例,分别对两种遗传—模糊控制算法进行数值仿真分析,并与LQR最优控制结果进行比较。数值分析结果表明,采用遗传—模糊算法能够有效地减小结构的地震响应。  相似文献   

11.
A novel smart control system based on genetic algorithms (GAs) is proposed in this paper. The system is comprised of three parts: the fiber Bragg grating (FBG) sensor‐based sensing network for structural health monitoring, the GA‐based location optimizer for sensor arrangement, and the GA‐based controller for vibration mitigation under external excitation. To evaluate the performance of the proposed system, an eight‐story steel structure was designed specifically to represent a structure with large degrees of freedom. In total 16 FBG sensors were deployed on the structure to implement the concept of a reliable sensing network, and to allow the structure to be monitored precisely under any loading. The advantage of applying a large amount of information from the sensing system is proven theoretically by the GA‐based location optimizer. This result greatly supports the recent tendency of distributing sensors around the structure. Two intuitive GA‐based controllers are then proposed and demonstrated numerically. It is shown that the structure can be controlled more effectively by the proposed GA‐strain controller than by the GA‐acceleration controller, which represents the traditional control method. A shaking table test was carried out to examine the entire system. Experimental verification has demonstrated the feasibility of using this system in practice. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

12.
Structural vibration control using active or passive control strategy is a viable technology for enhancing structural functionality and safety against natural hazards such as strong earthquakes and high wind gusts. Both the active and passive control systems have their limitations. The passive control system has limited capability to control the structural response whereas the active control system depends on external power. The power requirement for active control of civil engineering structures is usually quite high. Thus, a hybrid control system is a viable solution to alleviate some of the limitations. In this paper a multi‐objective optimal design of a hybrid control system for seismically excited building structures has been proposed. A tuned mass damper (TMD) and an active mass driver (AMD) have been used as the passive and active control components of the hybrid control system, respectively. A fuzzy logic controller (FLC) has been used to drive the AMD as the FLC has inherent robustness and ability to handle the non‐linearities and uncertainties. The genetic algorithm has been used for the optimization of the control system. Peak acceleration and displacement responses non‐dimensionalized with respect to the uncontrolled peak acceleration and displacement responses, respectively, have been used as the two objectives of the multi‐objective optimization problem. The proposed design approach for an optimum hybrid mass damper (HMD) system, driven by FLC has been demonstrated with the help of a numerical example. It is shown that the optimum values of the design parameters of the hybrid control system can be determined without specifying the modes to be controlled. The proposed FLC driven HMD has been found to be very effective for vibration control of seismically excited buildings in comparison with the available results for the same example structure but with a different optimal absorber. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

13.
The integrated optimum problem of structures subjected to strong earthquakes and wind excitations, optimizing the number of actuators, the configuration of actuators and the control algorithms simultaneously, is studied. Two control algorithms, optimal control and acceleration feedback control, are used as the control algorithms. A multi‐level optimization model is proposed with respect to the solution procedure of the optimum problem. The characteristics of the model are analysed, and the formulation of each suboptimization problem at each level is presented. To solve the multi‐level optimization problem, a multi‐level genetic algorithm (MLGA) is proposed. The proposed model and MLGA are used to solve two multi‐level optimization problems in which the optimization of the number of actuators, the positions of actuators and the control algorithm are considered in different levels. In problem 1, an example structure is excited by strong wind, and in problem 2, an example structure is subjected to strong earthquake excitation. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

14.
巨子型有控结构体系中黏滞阻尼器参数研究   总被引:2,自引:0,他引:2  
巨子型有控结构体系(Mega-sub Controlled Structure System,即MSCSS)是一种新型的超高层建筑结构体系.本文针对MSCSS的构造特点,提出一种安装黏滞阻尼器的新的布置方案,通过研究该布置方案中取不同黏滞阻尼器参数时巨子型有控结构体系在罕遇地震作用下的动力响应,提出了与该结构体系动力特...  相似文献   

15.
In the field of civil engineering, magnetorheological fluid (MRF) damper-based semi-active control systems have received considerable attention for use in protecting structures from natural hazards such as strong earthquakes and high winds. In this paper, the MRF damper-based semi-active control system is applied to a long-span spatially extended structure and its feasibility is discussed. Meanwhile, a _trust-region method based instantaneous optimal semi-active control algorithm (TIOC) is proposed to improve the performance of the semi-active control system in a multiple damper situation. The proposed TIOC describes the control process as a bounded constraint optimization problem, in which an optimal semi- active control force vector is solved by the trust-region method in every control step to minimize the structural responses. A numerical example of a railway station roof structure installed with MRF-04K dampers is presented. First, a modified Bouc- Wen model is utilized to describe the behavior of the selected MRF-04K damper. Then, two semi-active control systems, including the well-known clipped-optimal controller and the proposed TIOC controller, are considered. Based on the characteristics of the long-span spatially extended structure, the performance of the control system is evaluated under uniform earthquake excitation and travelling-wave excitation with different apparent velocities. The simulation results indicate that the MR fluid damper-based semi-active control systems have the potential to mitigate the responses of full-scale long-span spatially extended structures under earthquake hazards. The superiority of the proposed TIOC controller is demonstrated by comparing its control effectiveness with the clipped-optimal controller for several different cases.  相似文献   

16.
为了研究新型电磁惯性质量阻尼器(Electromagnetic Inertial Mass Damper,EIMD)应用于偏心高层结构振动控制工程的可行性,鉴于半主动控制技术的优点,基于LQR主动控制算法,提出一种可行的EIMD-偏心高层结构半主动控制策略,同时研究EIMD在结构每层中安装位置不同对于控制偏心高层结构扭转反应的影响。以一个实体24层偏心高层结构作为研究对象验证地震作用下所提控制策略的有效性,仿真结果表明:(1)所提半主动控制策略基本能够达到主动控制对于结构振动反应分量的控制效果;(2)当采用半主动控制策略时,调整EIMD的安装位置对于偏心高层结构转角和转角加速度反应有着较好的控制效果。  相似文献   

17.
本文建立了用ER/MR智能阻尼器耦联的带裙房高层建筑结构地震反应半主动控制的设计计算方法,文中,在导出ER/MR智能阻尼器力学模型的基础上,建立了ER/MR智能阻尼器耦联的带裙房层建筑结构地震反应的基本方程,并根据瞬时最优主动控制的原则,提出了ER/MR智能阻尼器耦联的带裙房高层建筑地震反应半主动控制的基于最优主动控制位移的“开关-耗能”半主动控制策略,应用本文方法对主楼20层,裙房5层的计算结构;受控地震反应的模拟计算结构表明,耦联主楼和裙房的半主动的ER/MR智能阻尼器可有效地抑制带裙房高层建筑结构地震反应的鞭梢效应,并可均匀地减小结构各层的震反应,是一种简单,方便和有效的智能控制装置。  相似文献   

18.
A fuzzy‐logic control algorithm, based on the fuzzification of the MR damper characteristics, is presented for the semiactive control of building frames under seismic excitation. The MR damper characteristics are represented by force–velocity and force–displacement curves obtained from the sinusoidal actuation test. The method does not require any analytical model of MR damper characteristics, such as the Bouc‐Wen model, to be incorporated into the control algorithm. The control algorithm has a feedback structure and is implemented by using the fuzzy‐logic and Simulink toolboxes of MATLAB. The performance of the algorithm is studied by using it to control the responses of two example buildings taken from the literature—a three‐storey building frame, in which controlled responses are obtained by clipped‐optimal control and a ten‐storey building frame. The results indicate that the proposed scheme provides nearly the same percentage reduction of responses as that obtained by the clipped‐optimal control with much less control force and much less command voltage. Position of the damper is found to significantly affect the controlled responses of the structure. It is observed that any increase in the damper capacity beyond a saturation level does not improve the performance of the controller. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

19.
Optimal design of viscoelastic dampers using eigenvalue assignment   总被引:1,自引:0,他引:1  
In this study a procedure for determining the optimum size and location of viscoelastic dampers is proposed using the eigenvalue assignment technique. Natural frequencies and modal damping ratios, required to realize a given target response, are determined first by the convex model. Then the desired dynamic structural properties are realized by optimally distributing the damping and stiffness coefficients of viscoelastic dampers using non‐linear programming based on the gradient of eigenvalues. This optimization method provides information on the optimal location as well as the magnitude of the damper parameters. The proposed procedure is applied to the retrofit of a 10‐story shear frame, and to a three‐dimensional structure with an asymmetric plan. The analysis results confirm that the responses of model structures retrofitted by the proposed method correspond well with the given target response. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

20.
A semi‐active fuzzy control strategy for seismic response reduction using a magnetorheological (MR) damper is presented. When a control method based on fuzzy set theory for a structure with a MR damper is used for vibration reduction of a structure, it has an inherent robustness, and easiness to treat the uncertainties of input data from the ground motion and structural vibration sensors, and the ability to handle the non‐linear behavior of the structure because there is no longer the need for an exact mathematical model of the structure. For a clipped‐optimal control algorithm, the command voltage of a MR damper is set at either zero or the maximum level. However, a semi‐active fuzzy control system has benefit to produce the required voltage to be input to the damper so that a desirable damper force can be produced and thus decrease the control force to reduce the structural response. Moreover, the proposed control strategy is fail‐safe in that the bounded‐input, bounded‐output stability of the controlled structure is guaranteed. The results of the numerical simulations show that the proposed semi‐active control system consisting of a fuzzy controller and a MR damper can be beneficial in reducing seismic responses of structures. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

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