• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.331-334
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• 2010

본 논문에서는 준능동 TMD가 설치된 고층건물의 풍응답을 효과적으로 저감시키기 위하여 다목적 유전자알고리즘(MOGA)을 이용한 퍼지관리제어기를 개발하였다. 퍼지관리제어기는 하위제어기인 그라운드훅(groundhook) 제어알고리즘과 스카이훅(skyhook) 제어알고리즘에 의해서 결정된 제어명령을 적절하게 하나로 합치는 역할을 한다. 다목적 유전자알고리즘의 최적화 과정에서 75층의 가속도 응답과 준능동 TMD의 변위응답을 목적함수로 사용하였다. 다목적 유전자알고리즘 최적화과정을 통하여 퍼지관리제어기의 파레토 최적해집합을 효과적으로 얻을 수 있었다. 다목적 유전자알고리즘에 의하여 개발된 퍼지관리제어기는 가중합방법의 제어기보다 매우 우수한 성능을 나타내었다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.5
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• pp.465-474
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• 2008

The real-time hybrid testing method(RT-HYTEM) is a structural testing technique in which the numerical integration of the equation of motion for a numerical substructure and the physical testing for an experimental substructure are performed simultaneously in real-time. This study presents the quantitative evaluation of the seismic performance of a building structure installed with an passive and semi-active MR damper by using RT-HYTEM. The building model that was identified from the force-vibration testing results of a real-scaled 5-story building is used as the numerical substructure, and an MR damper corresponding to an experimental substructure is physically tested by using the universal testing machine(UTM). The RT-HYTEM implemented in this study is validated because the real-time hybrid testing results obtained by application of sinusoidal and earthquake excitations and the corresponding analytical results obtained by using the Bouc-Wen model as the control force of the MR damper respect to input currents were in good agreement. Also for preliminary study, some semi-active control algorithms were applied to the MR damper in order to control the structural responses optimally. Comparing between the test results of semi-active control using RT-HYTEM and numerical analysis results show that the RT-HYTEM is more resonable than numerical analysis to evaluate the performance of semi-active control algorithms.

• Journal of Korean Association for Spatial Structures
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• v.11 no.2
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• pp.101-110
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• 2011

Many researchers have attempted to apply semi-active control systems in the civil engineering structures. Recently, magneto-rheological(MR) fluid dampers have been developed. This MR damper is one of semi-active dampers as a new class of smart dampers. This paper discusses the application of MR damper for seismic response control of adjacent buildings subjected to earthquake. Here, a controllable damping force of MR damper that is installed between adjacent buildings is applied to seismic response control. A hybrid model combines skyhook and groundhook control algorithm so that the benefits of each can be combined together. In this paper, hybrid control model are applied to the multi degree of freedom system representative of buildings in order to reduce seismic response of adjacent buildings. And the performance of hybrid control model is compared with that of others. It was demonstrated that hybrid control model or adjacent buildings with MR damper was effective for seismic response control of two adjacent buildings reciprocally.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.1
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• pp.219-224
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• 2016

The vibration control performance of a semi-active damper connected to adjacent buildings subjected to seismic loads was investigated. The MR damper was used as a semi-active control device. A fuzzy logic control algorithm was used for effective control of the adjacent buildings connected to the MR damper. In the buildings control coupled with a MR damper, the response reduction of one building results in an increase in the response in another building. Because of these conflict characteristics, multi-objective optimization is required. Therefore, a fuzzy logic control algorithm for the control of a MR damper was optimized using a multi-objective genetic algorithm. Based on numerical analyses, the semi-active fuzzy control of MR damper for adjacent coupled buildings can provide good control performance.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.2
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• pp.255-262
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• 2008

In this study, seismic response control performance of decentralized response-dependent MR damper which generates the control force using only the response of damper-installed floor, was experimentally investigated through the tests of a full-scale structure installed with large MR dampers. The performance of the decentralized control algorithm was compared to those of the centralized ones such as Lyapunov, modulated homogeneous friction, and clipped-optimal control. Hybrid mass damper were controlled to induce seismic response of the full-scale structure under El Centro earthquake. Experimental results indicated that the proposed decentralized MR damper provided superior or equivalent performance to centralized one in spite of using damper-installed floor response for calculating input voltage to MR damper.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2009.04a
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• pp.433-436
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• 2009

본 연구에서는 준능동 TMD(STMD)가 설치된 초고층건물의 풍응답을 효과적으로 저감시키기 위한 퍼지 하이브리드제어기법을 제안하였다. 이를 위하여 STMD의 응답저감에 우수한 성능을 보이는 스카이훅(skyhook) 제어기와 구조물의 응답저감에 뛰어난 그라운드훅(groundhook) 제어알고리즘을 사용하였다. 본 연구에서는 두 제어기를 적절히 조합하기 위하여 최적의 가중치를 실시간으로 결정하는 퍼지 하이브리드제어기를 개발함으로써 일반적인 가중합방식의 하이브리드 제어기법의 성능을 개선하였다. 제안된 제어기의 성능을 검토하기 위하여 풍하중을 받는 76층 사무소 건물을 예제구조물로 사용하였다. MR 감쇠기를 이용하여 STMD를 구성하였고 STMD의 제어성능을 평가하기 위하여 TMD 및 ATMD의 성능과 비교하였다. 수치해석을 통하여 STMD의 제어성능이 TMD에 비하여 월등히 뛰어남을 확인할 수 있었다. 또한 퍼지 하이브리드 제어기법을 사용하면 스카이훅 및 그라운드훅 제어기를 효과적으로 조합하여 STMD와 건물의 응답을 동시에 줄일 수 있음을 확인하였다.

• Journal of the Earthquake Engineering Society of Korea
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• v.10 no.1 s.47
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• pp.51-62
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• 2006

To dale, lots of types of tuned mass dampers are developed and investigated to reduce dynamic responses of a structure due to various causes. In this study, control performance of semi-active tuned mass damper(STMD), that can change the damping of tuned mass damper in real time based on structural responses, was investigated with respect to various types of excitation employing numerical simulation. Skyhook control algorithm was used to appropriately modulate the damping ratio of semi-active damper that composes STMD. The control effectiveness of a STMD under harmonic and random excitation were evaluated using a single-degree-of-freedom (SDOF) structure in comparison with a conventional passive tuned mass damper (TMD). The robustness of a STMD and a passive TMD were compared along with the variation of the mass of a SDOF structure. The control performance of STMD using magnetorheological (MR) damper was also investigated in this study. Based on the numerical studios, it was shown that the control effectiveness of the STMD was significantly superior to that of a passive TMD with respect to harmonic and random excitation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.648-654
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• 2007

This paper presents the result of a comparison study to evaluate the performance of several semi-active control algorithms for use with large-scale MR damper applied to a building structure under seismic excitation using real-time hybrid test method. Recently, a variety of semi-active control algorithm studies are developed and generally evaluated the performance by using numerical analysis. In this paper real-time hybrid test method was applied to performance evaluating of semi-active control algorithms including a clipped optimal algorithm and the modulated homogeneous friction algorithm.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.6
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• pp.761-767
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• 2007

In centralized control system, complicated control systems including sensors, power supply and dampers should be required to satisfy the target response of large-scale structures. The practical applications of the centralized control system, however, is very difficult due to high order finite element model of structures, uncertainty of models, and limitations of the excitation system. In this study, the decentralized response-dependent MR damper of which magnetic field is automatically modulated according to the displacement or velocity transferred to the damper without any sensing and computing systems. this decentralized response-dependent MR damper are investigated according to the ranges of relative magnitude between the control force of MR damper and the story shear force of structures by nonlinear time history analysis. Finally, its performance is compared with centralized LQR algorithm which is used in general centralized control theory for a three story building structure.

• Journal of Korean Association for Spatial Structures
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• v.10 no.1
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• pp.103-110
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• 2010

In this study, the possibility of seismic response control of semi-active tuned mass damper (TMD) for spatial structures has been investigated. To this end, an arch structure was used as an example structure because it has primary characteristics of spatial structures and it is a comparatively simple structure. A TMD and semi-active TMD were applied to the example arch structure and the seismic control performance of them were evaluated based on the numerical simulation. In order to regulate the damping force of the semi-active TMD, groundhook control algorithm, which is widely used for semi-active control, was used. El Centro (1940) and Northridge (1994) earthquakes and harmonic ground motion were used for performance evaluation of passive TMD and semi-active TMD. Based on the analytical results, the passive TMD could effectively reduce the seismic responses of the arch structure and it has been shown that the semi-active TMD more effectively decreased the dynamic responses of the arch structure compared to the passive TMD with respect to all the excitations used in this study.