Response Control Performance Evaluation of MR Damper by Shaking Table Tests and Real-Time Hybrid Tests

2008 ◽  
Vol 56 ◽  
pp. 212-217 ◽  
Author(s):  
Hideo Fujitani ◽  
Hiroaki Sakae ◽  
Mai Ito ◽  
Takeshi Hiwatashi

Magnetorheological damper (MR damper) has been expected to control the response of civil and building structures in recent years, because of its large force capacity and variable force characteristics. In this paper, a series of real-time hybrid test was conducted and the results of real time hybrid tests were compared to those of shaking table tests. To determine the control force of the MR damper, skyhook control and sliding mode control theory were employed. As the results, the validity of real-time hybrid test was verified. This paper describes the capability of MR damper to control the structural response.

2020 ◽  
Vol 10 (11) ◽  
pp. 4037 ◽  
Author(s):  
Okpin Na ◽  
Jejin Park

Real-time hybrid method is an economical and efficient test method to evaluate the dynamic behavior. The purpose of this study is to develop the computational algorithm and to prove the reliability of a real-time hybrid control system. For performing the multi-direction dynamic test, three dynamic actuators and the optimized real-time hybrid system with new hybrid simulation program (FEAPH) and a simplified inter-communication were optimized. To verify the reliability and applicability of the real-time hybrid control system, 3-DOF (3 Degrees of Freedom) non-linear dynamic tests with physical model were conducted on a steel and concrete frame structure. As a ground acceleration, El Centro and Northridge earthquake waves were applied. As a result, the maximum error of numerical analysis is 13% compared with the result of shaking table test. However, the result of real-time hybrid test shows good agreement with the shaking table test. The real-time hybrid test using FEAPH can make good progress on the total testing time and errors. Therefore, this test method using FEAPH can be effectively and cheaply used to evaluate the dynamic performance of the full-scale structure, instead of shaking table and full-scale test.


2015 ◽  
Vol 21 (8) ◽  
pp. 967-976 ◽  
Author(s):  
Nengmou Wang ◽  
Hojjat Adeli

A robust filtered sliding mode control (SMC) approach is presented for vibration control of wind-excited highrise building structures. Rather than using a Lyapunov-function based control design, an alternative way is provided to find the control force based on the equivalent control force principle to obtain the control force. A low pass filter is properly selected to remove the high-frequency components of the control force while retaining the structural stability. The performance of the proposed filtered SMC is evaluated by application to a wind-excited 76-story building benchmark problem equipped with an active tuned mass damper (ATMD) on the roof. Due to the elimination of high-frequency part of the control force, the structure, sensors, actuators, and dampers are all less excited, and consequently their response is reduced compared with the unfiltered SMC approach. In addition, the required control forces are reduced which means a reduction in the size of actuators, thus making their implementation more practical. It is shown the proposed method is more robust to structural stiffness uncertainties compared with the linear quadratic Gaussian (LQG) algorithm and another implementation of SMC.


Author(s):  
Satoshi Yamada ◽  
Yuka Matsumoto ◽  
Michio Yamaguchi ◽  
Nobuyuki Ogawa ◽  
Akira Wada ◽  
...  

In this paper, a new experimental method of full scale real time shaking table test of structural element is introduced. The main feature of this experimental method is characterized by the use of the inertial loading equipment. The inertial loading equipment consists of a loading frame, a counter weight and isolators. The loading frame supported by the isolators was set on the shaking table. Specimens used in this experimental method were partial frames taken out from full scale building structures. The test set-up was composed of a specimen, the inertial loading equipment and loading beam which transmits the horizontal force to the specimen from the inertial loading equipment. This test set-up, regarded as a single degree of freedom system, makes it easy to understand the dynamic behavior of the test set-up including a specimen. Furthermore, the natural period of the experimental system corresponds to the fundamental natural period of existing building structures. So, full scale and real time dynamic loading test of partial frame can be realized. This method was developed for the existing large scale shaking table and the effectiveness has been already verified through many experiments. Further development of the experimental method adjusted to the 3-D largest shaking table under construction at present is also described.


Author(s):  
Eunchurn Park ◽  
Sung-Kyung Lee ◽  
Heon-Jae Lee ◽  
Seok-Joon Moon ◽  
Hyung-Jo Jung ◽  
...  

This study introduces the quantitative evaluation of the seismic performance of a building structure equipped with MR dampers by using real-time hybrid testing method (RT-HYTEM). A real-scaled 5-story building is used as the numerical substructure, and MR dampers corresponding to an experimental substructure is physically tested by using UTM. First, the force required to drive the displacement of the story, at which the MR damper is located, is measured from the load cell attached to UTM. Then, the measured force is returned to a control computer to calculate the response of the numerical substructure. Finally, the experimental substructure is excited by UTM with the calculated response of the numerical substructure. The RT-HYTEM implemented in this study is validated for that 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. Furthermore, semi-active control algorithms were applied to the MR damper. The comparison results of experimental and numerical responses demonstrated that using RT-HYTEM was more reasonable in semi-active devices such as MR dampers having strong nonlinearity.


Author(s):  
Yen-Po Wang ◽  
Di-Hung Chen ◽  
Chien-Liang Lee

An innovative displacement-dependent metallic yielding damper designed to deform inelastically under in-plane flexural bending for seismic protection of building structures is proposed. The in-plane flexural damper that originated from a portal frame is modified by replacing the beam with a circular arch so that the effect of stress concentration can be minimized. Component tests of the in-plane dampers were conducted and compared with analytical results. Hysteresis of the component test indicates a consistent energy-dissipative characteristic of the damper. Moreover, seismic performance of the proposed damper via a series of shaking table tests was carried out. Excellent seismic performance of the proposed in-plane arched damper was observed. The acceleration responses in both peak and root-mean-squares of all floors are significantly reduced, and were greater in extent compared to the earthquake intensity increases.


Author(s):  
Jagadish G. Kori ◽  
R.S. Jangid

Magnotorheological (MR) dampers have been demonstrated to be more effective in reducing the structural response due to earthquakes using only a small amount of external power. The performance of MR damper depends upon type of control law used and the damper force is directly depends on the input command voltage. The purpose of this study is to evaluate the effectiveness of input command voltage on MR damper system against recently proposed control laws under different earthquakes. The magnitude of control force increases with the increase in the input command voltage of MR damper, however for the different damper locations and configurations maximum command voltage to the current driver may not always effective in reducing the structural responses. To investigate the effective performance of the MR dampers, different control algorithms with multiple MR damper locations are considered in this study. A phenomenological model of a shear- mode MR damper, based on a Bouc–Wen element, is employed in the analysis of the controlled building. The control algorithms are tested on a five-story framed building and parametric study on variation in the input command voltage is conducted for different real earthquake ground motions. The numerically evaluated optimum parametric values are considered for the analysis of the different damper locations in the building in order to reduce the displacement, acceleration and the base shear of the building. It is shown numerically that the performance of the MR damper has a great potential in suppressing structural vibrations over a wide range of seismic inputs by selecting appropriate optimum input command voltages.


Sign in / Sign up

Export Citation Format

Share Document