基于电磁摩擦控制装置的被动智能控制研究

本文将电磁摩擦控制装置应用于结构被动智能控制。分析了电磁摩擦控制装置的恢复力特性及影响参数，建立了被动连续变刚度体系的理论模型，推导了受控结构系统的一般方程，进行了模型结构的被动智能控制仿真分析。从理论上验证了：电磁摩擦控制装置用于结构被动智能控制具有良好的控制效果。     

无能源磁摩擦控制装置性能试验研究

本文提出了一种智能型无能源磁摩擦控制装置的设计思想，制作了无能源磁摩擦控制装置模型－永磁铁摩擦耗能装置模型。通过该装置的性能试验研究，获得了无能源磁摩擦控制装置的滞回性能曲线。由于可通过改变有效磁极面积使摩擦力由恒定转为连续可变，即该装置的摩擦力随位移的变化可连续、可逆、迅速地改变，因此该装置具有明显的自适应性。     

摩擦消能支撑装置非线性刚度分析

多层建筑结构中设置摩擦消能支撑是以“柔性消能”减小地震反应，实现结构被动控制的有效途径之一，本文通过分析和计算I0型，IIb型两种摩擦消能支撑装置在各种形状态下的单元刚度矩阵[KNL(t)]，为摩消能减震结构体系在地震作用下的非线性进程分析提供了消能支撑单元的精确理论模型。     

两个控制装置的模拟地震振动台试验研究

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。     

支撑刚度对磁摩擦耗能减振体系的影响

本文在已有磁摩擦耗能减振体系振动台试验基础上，讨论了两类磁摩擦耗能减振体系支撑刚度的影响，揭示了支撑刚度对磁摩擦耗能装置减振效果的影响规律，给出了两类磁摩擦耗能装置在结构中发挥最佳减振效果时支撑刚度的取值范围。     

基于瞬时最优算法的磁流变阻尼隔震结构半主动控制

采用瞬时最优控制算法，对附加了磁流变阻尼器的多自由度隔震结构进行了半主动控制的数值模拟。首先，将被动隔震装置——叠层钢板橡胶垫与磁流变阻尼器相结合，形成磁流变智能隔震系统。其次，根据瞬时最优控制算法的基本原理，针对磁流变阻尼器的特点，建立与之相适应的半主动控制算法。最后，以六层隔震结构为例，进行数值分析。比较了被动与半主动控制的结构反应，并得到较好的控制效果。     

安装被动耗能装置的结构的抗震设计方法

依据现行抗震设防的目标和思想,从经济、实用的角度提出了安装被动耗能装置的结构的抗震设计方法,即结构件在地震作用适当降低的基础上独立进行截面设计,然后在结构上安装被动耗能装置后进行与设防烈度对应的多遇地震弹性变形验算和罕遇弹塑性变形验算。     

混合水箱装置对高层建筑结构地震反应控制效果的研究

提出了一种用于结构地震反应控制的混合水箱装置的设想，通过优化计算进行了装置的参数选取，并探讨了该装置的频率设计方法，算例的弹塑性时程分析结果表明，混合水箱装置增加了液体的质量，具有相对较宽的工作效率，是一种适应性较强的被动控制装置。     

电磁摩擦控制装置性能试验研究

本文提出了利用电磁铁的磁力效应设计电磁摩擦控制装置的思想，制作了电磁摩擦控制装置模型。通过该装置模型的性能试验研究，获得了其滞回性能曲线。由于可通过改变通电电流使摩擦力由恒定转为连续可变，电磁摩擦控制装置具有明显的自适应性。     

相邻结构的高效阻尼控制

提出了相邻结构高效阻尼控制的概念,并基于双液缸的放大原理提出了一处相应的装置,该装置通过放大相邻结构间的振动差别,使阻尼器具有更大的变形和速度,从而更高效地工作,文章阐明了该装置的工作原理,建立了两相邻结构高效阻尼控制体系的运动方程,并对此进行了计算机仿真分析,结果表明,高效阻尼控制的概念是正常的,本文提出的控制装置是有效的,可取得远优于普通阻尼控制的效果。     

Shaking table tests on reinforced concrete frames without and with passive control systems

An extensive experimental program of shaking table tests on reduced‐scale structural models was carried out within the activities of the MANSIDE project, for the development of new seismic isolation and energy dissipation devices based on shape memory alloys (SMAs). The aim of the experimental program was to compare the behaviour of structures endowed with innovative SMA‐based devices to the behaviour of conventional structures and of structures endowed with currently used passive control systems. This paper presents a comprehensive overview of the main results of the shaking table tests carried out on the models with and without special braces. Two different types of energy dissipating and re‐centring braces have been considered to enhance the seismic performances of the tested model. They are based on the hysteretic properties of steel elements and on the superelastic properties of SMAs, respectively. The addition of passive control braces in the reinforced concrete frame resulted in significant benefits on the overall seismic behaviour. The seismic intensity producing structural collapse was considerably raised, interstorey drifts and shear forces in columns were drastically reduced. Copyright © 2005 John Wiley & Sons, Ltd.     

Recent advances in structural control research and applications in China mainland

Abstrect The recent developments of theoretical research, model tests and engineering applications of structural control in mainland China are reviewed in this paper. It includes seismic isolation, passive energy dissipation, active and semi-active control, smart materials and smart structural systems. It can be seen that passive control methods, such as seismic isolation and energy dissipation methods, have developed into the mature stage in China. At the same time, great progress has been made in active and semi-active control, and smart actuators or smart dampers and smart structural systems. Finally, some future research initiatives for structural control in civil engineering are suggested. Supported by : National Natural Science Foundation of China (Grant No. 50025821)     

Predictive control of seismic structures with semi‐active friction dampers

In this paper a predictive control method especially suitable for the control of semi‐active friction dampers is proposed. By keeping the adjustable slip force of a semi‐active friction damper slightly lower than the critical friction force, the method allows the damper to remain in its slip state throughout an earthquake of arbitrary intensity, so the energy dissipation capacity of the damper can be improved. The proposed method is formulated in a discrete‐time domain and cast in the form of direct output feedback for easy control implementation. The control algorithm is able to produce a continuous and smooth slip force for a friction damper and thus avoid exerting the high‐frequency structural response that usually exists in structures with conventional friction dampers. Using a numerical study, the control performance of a multiple degrees of freedom (DOF) structural system equipped with passive friction dampers and semi‐active dampers controlled by the proposed method are compared. The numerical case shows that by merely using a single semi‐active friction damper and a few sensors, the proposed method is able to achieve better acceleration reduction than the case using multiple passive dampers. Copyright © 2004 John Wiley & Sons, Ltd.     

Fuzzy logic control of bridge structures using intelligent semi-active seismic isolation systems

Passive supplemental damping in a seismically isolated structure provides the necessary energy dissipation to limit the isolation system displacement. However, damper forces can become quite large as the passive damping level is increased, resulting in the requirement to transfer large forces at the damper connections to the structure which may be particularly difficult to accommodate in retrofit applications. One method to limit the level of damping force while simultaneously controlling the isolation system displacement is to utilize an intelligent hybrid isolation system containing semi-active dampers in which the damping coeffic ient can be modulated. The effectiveness of such a hybrid seismic isolation system for earthquake hazard mitigation is investigated in this paper. The system is examined through an analytical and computational study of the seismic response of a bridge structure containing a hybrid isolation system consisting of elastomeric bearings and semi-active dampers. Control algorithms for operation of the semi-active dampers are developed based on fuzzy logic control theory. Practical limits on the response of the isolation system are considered and utilized in the evaluation of the control algorithms. The results of the study show that both passive and semi-active hybrid seismic isolation systems consisting of combined base isolation bearings and supplemental energy dissipation devices can be beneficial in reducing the seismic response of structures. These hybrid systems may prevent or significantly reduce structural damage during a seismic event. Furthermore, it is shown that intelligent semi-active seismic isolation systems are capable of controlling the peak deck displacement of bridges, and thus reducing the required length of expansion joints, while simultaneously limiting peak damper forces. Copyright © 1999 John Wiley & Sons, Ltd.     

Design of passive systems for control of inelastic structures

A design strategy for control of buildings experiencing inelastic deformations during seismic response is formulated. The strategy is using weakened, and/or softened, elements in a structural system while adding passive energy dissipation devices (e.g. viscous fluid devices, etc.) in order to control simultaneously accelerations and deformations response during seismic events. A design methodology is developed to determine the locations and the magnitude of weakening and/or softening of structural elements and the added damping while insuring structural stability. A two‐stage design procedure is suggested: (i) first using a nonlinear active control algorithm, to determine the new structural parameters while insuring stability, then (ii) determine the properties of equivalent structural parameters of passive system, which can be implemented by removing or weakening some structural elements, or connections, and by addition of energy dissipation systems. Passive dampers and weakened elements are designed using an optimization algorithm to obtain a response as close as possible to an actively controlled system. A case study of a five‐story building subjected to El Centro ground motion, as well as to an ensemble of simulated ground motions, is presented to illustrate the procedure. The results show that following the design strategy, a control of both peak inter‐story drifts and total accelerations can be obtained. Copyright © 2008 John Wiley & Sons, Ltd.     

可控消能减震原理及结构分析

本文介绍一种新的减震结构体系及其分析方法。这种结构体系的减震系统由控制装置及耗能装置组成，控制装置根据结构反馈的相关信号，在回头点处启动耗能装置，耗散大量地震能量，属于半主动控制范畴。试验及理论分析表明，这种结构体系的减震效果良好，能够将结构的地震位移反应降低５０％以上。本文介绍了这种结构体系的减震工作原理、数学模型、理论分析方法及算例，并给出了相应的结论。     

静力分析方法在消能减震结构分析中的应用

由于受制于计算机软件中的消能减震单元,目前尚无较适用的静力分析方法应用于消能减震结构在多遇地震和罕遇地震下的结构分析。有关含消能减震部件的结构分析,主要以动力时程分析和动力弹塑性时程分析方法为主,因此具有较大的难度和需要很长的分析时间。为了推进结构消能减震于工程项目上的应用,缩短分析上的繁杂程序,依据《建筑抗震设计规范》,配合美国FEMA 356规范,提出一套消能减震结构在多遇地震下的等值线性分析方法和在罕遇地震下的静力非线性推覆分析方法（pushover analysis）。此方法适用于位移型阻尼器和防屈曲支撑,不但可使消能减震结构的结构分析简化,并可避免计算机软件的限制,且在不含阻尼器元素的计算机软件上,依然可做消能减震结构在多遇地震和罕遇地震下的结构分析。并介绍了此分析方法在消能减震结构的结构分析中的应用,以证明其可行性。     

A novel bidirectional pendulum tuned mass damper using variable homogeneous friction to achieve amplitude-independent control

Passive tuned mass dampers (TMDs) are widely used in controlling structural vibrations. Although their principle is well established, the search for improved arrangements is still under way. This effort has recently produced an innovative paradigm of bidirectional pendulum TMD (BTMD) that, moving along a specially designed three-dimensional (3D) surface, can simultaneously control two in-plane orthogonal structural modes. In existing versions of BTMDs, energy dissipation is provided either by ordinary horizontal viscous dampers or by an original arrangement of vertical friction dampers. In this paper, a new paradigm is proposed, in which energy dissipation comes from the tangential friction arising along the pendulum surface out of an optimal spatially variable friction coefficient pattern. Within this paradigm, if the friction coefficient is taken proportional to the modulus of the pendulum surface gradient, the dissipation model results nonlinear homogeneous in the small-displacement domain, and the performance of the absorber, herein called the homogeneous tangential friction BTMD (HT-BTMD), results independent from the excitation level. The present work introduces this concept, derives the analytical model of the HT-BTMD, establishes a method for its optimal design, and numerically verifies its seismic effectiveness in comparison with viscously damped devices. The validity and feasibility of the concept are demonstrated through experimental tests on a small-scale lab prototype, which also show the efficacy of a stepwise approximation of the homogeneous friction pattern. The new device proves a competing alternative to existing BTMDs, and homogeneous tangential friction proves a promising new paradigm to provide pendular systems with amplitude-independent structural damping.