scholarly journals Shared Tuned Mass Dampers for Mitigation of Seismic Pounding

2020 ◽  
Vol 10 (6) ◽  
pp. 1918 ◽  
Author(s):  
Rajesh Rupakhety ◽  
Said Elias ◽  
Simon Olafsson

This study explores the effectiveness of shared tuned mass damper (STMD) in reducing seismic pounding of adjacent buildings. The dynamics of STMDs is explored through numerical simulations of buildings idealized as single and multiple degree of freedom oscillators. An optimization method proposed in the literature is revisited. It is shown that the optimization results in two different solutions. The first one corresponds to the device being tuned to one of the buildings it is attached to. The second solution corresponds to a very stiff system where the TMD mass hardly moves. This solution, which has been described as an STMD in the literature, is shown to be impractical due to its high stiffness and use of a heavy stationary mass that plays no role in response mitigation but adds unnecessary load to the structure. Furthermore, it is shown that the second solution is equivalent to a viscous coupling of the two buildings. As for the properly tuned solution, i.e., the first solution, sharing the device with an adjacent building was found to provide no added benefits compared to when it is placed on one of the buildings. Based on results from a large set of real earthquake ground motions, it is shown that sharing a TMD mass with an adjacent building, in contrary to what is reported in the literature, is not an effective strategy.

2022 ◽  
pp. 136943322110509
Author(s):  
Xuan Zhang ◽  
Qiang Han ◽  
Kaiming Bi ◽  
Xiuli Du

Multiple vibration modes of an engineering structure might be excited by earthquake ground motions. Multiple tuned mass dampers (MTMDs) are widely used to control these multi-mode vibrations. However, in the commonly used MTMD system, the mass element in each tuned mass damper (TMD) is normally assumed to be the same. To improve the performance of MTMDs for seismic-induced vibration control, non-uniform MTMD masses are adopted in the present study to improve the mass utilization of TMD, and a location factor is proposed to determine the best location of each TMD in the MTMD system. The effectiveness of the proposed method is validated through numerical study. The results show that the proposed method effectively reduces the seismic responses of the structure induced by multiple vibration modes.


2020 ◽  
Vol 10 (4) ◽  
pp. 1230 ◽  
Author(s):  
Mohammad Hamayoun Stanikzai ◽  
Said Elias ◽  
Rajesh Rupakhety

Earthquake response mitigation of a base-isolated (BI) building equipped with (i) a single tuned mass damper at the top of the building, (ii) multiple tuned mass dampers (MTMDs) at the top of the building, and (iii) MTMDs distributed on different floors of the building (d-MTMDs) is studied. The shear-type buildings are modeled by considering only one lateral degree of freedom (DOF) at the floor level. Numerical approach of Newmark’s integration is adopted for solving the coupled, governing differential equations of motion of 5- and 10-story BI buildings with and without TMD schemes. A set of 40 earthquake ground motions, scaled 80 times to get 3200 ground motions, is used to develop simplified fragility curves in terms of the isolator maximum displacement. Incremental dynamic analysis (IDA) is used to develop simplified fragility curves for the maximum target isolator displacement. It is found that TMDs are efficient in reducing the bearing displacement, top floor acceleration, and base shear of the BI buildings. In addition, it was noticed that TMDs are efficient in reducing the probability of failure of BI building. Further, it is found that the MTMDs placed at the top floor and d-MTMDs on different floors of BI buildings are more efficient in decreasing the probability of failure of the BI building when compared with STMD.


Author(s):  
Thuan Nguyen ◽  
Nanako Miura ◽  
Akira Sone

Tuned mass damper (TMD) device has been a popular vibration control system for moderns as high-rise building, bridge to suppress excessive vibration due to environment or human loading. Moreover, multiple tuned mass dampers have received much attention in the researched. An optimal design theory for bridge implemented with multiple TMD devices is proposed in this paper. The proposed method chooses the objective function with the constraints on the peaks which are at the same heights over frequency ranges of interest. This proposed method successfully reduces vibration of bridge traveled by a car. In a future study, we will extend the optimal design theory for the cases with more than one car and the bridge under seismic loading.


2021 ◽  
pp. 107754632110359
Author(s):  
César A Morales

A novel design procedure for tuned mass dampers in isolated structures is presented. The proposed optimization method is specifically developed to control base displacements or to solve the large isolator displacement problem in this type of structures under earthquakes. Therefore, it is based on a displacement transmissibility function, T, a particular case of the general transmissibility concept, which comes from Vibration Isolation. Three contributions are application of new seismic displacement narrowbandness, simpler relative transmissibility function, and compound design of isolation plus tuned mass damper. A standard isolated model is used to show that the base displacement can be controlled at levels in the proximity of the ground motion ( T ≈ 1), which results in a positive comparison with previous isolation and tuned mass damper solutions; this is one of the main conclusions and it is based on novelty three above; in fact, other solutions in the literature compare their attained displacements with respect to the structure without tuned mass damper. Comparison with isolated results is not, therefore, possible herein, but it is not desirable either; actually, what is possible is a positive and more demanding comparison, which is with respect to the very seismic ground displacement itself. The large isolator displacement problem can be solved or attenuated by properly designing a tuned mass damper subsystem jointly with the isolation one.


2020 ◽  
Vol 26 ◽  
pp. 100-106
Author(s):  
Jan Štepánek ◽  
Jiří Máca

Tuned mass damper is a device, which can be highly useful when dealing with excessive vibration and is widely used in many engineering fields. However, its proper design and optimization is a complicated task. This study uses mode superposition method to speed up the evaluation of dynamic response. The speed of response calculation allows for a quick calculation of frequency response function and numerical optimization of tuned mass dampers. This optimization method is demonstrated on a numerical example of a cable stayed footbridge. The example compares a simplified and widely used design method of tuned mass damper with numerical optimization.


Tuned mass dampers (TMD) are one of the most reliable devices to control the vibration of the structure. The optimum mass ratio required for a single tuned mass damper (STMD) is evaluated corresponding to the fundamental natural frequency of the structure. The effect of STMD and Multiple tuned mass dampers (MTMD) on a G+20 storey structure are studied to demonstrate the damper’s effectiveness in seismic application. The location and number of tuned mass dampers are studied to give best structural performance in maximum reduction of seismic response for El Centro earthquake data. The analysis results from SAP 2000 software tool shows damper weighing 2.5% of the total weight of the structure effectively reduce the response of the structure. Study shows that introduction of 4-MTMD at top storey can effectively reduce the response by 10% more in comparison to single tuned mass damper. The use of MTMD of same mass ratio that of STMD is more effective in seismic response.


Author(s):  
E. Matta ◽  
R. Ceravolo ◽  
A. De Stefano ◽  
A. Quattrone ◽  
L. Zanotti Fragonara

2016 ◽  
Vol 20 (9) ◽  
pp. 1375-1389 ◽  
Author(s):  
Mohammad Sabbir Rahman ◽  
Md Kamrul Hassan ◽  
Seongkyu Chang ◽  
Dookie Kim

The primary objective of this research is to find the effectiveness of an adaptive multiple tuned mass damper distributed along with the story height to control the seismic response of the structure. The seismic performance of a 10-story building was investigated, which proved the efficiency of the adaptive multiple tuned mass damper. Structures with single tuned mass damper and multiple tuned mass dampers were also modeled considering the location of the dampers at the top of the structure, whereas adaptive multiple tuned mass damper of the structure was modeled based on the story height. Selection of the location of the adaptive multiple tuned mass damper along with the story height was dominated by the modal parameters. Participation of modal mass directly controlled the number of the modes to be considered. To set the stage, a comparative study on the displacements and modal energies of the structures under the El-Centro, California, and North-Ridge earthquakes was conducted with and without various types of tuned mass dampers. The result shows a significant capability of the proposed adaptive multiple tuned mass damper as an alternative tool to reduce the earthquake responses of multi-story buildings.


Author(s):  
Semen Kopylov ◽  
Zhaobo Chen ◽  
Mohamed AA Abdelkareem

Implementation of tuned mass dampers is the commonly used approach to avoid excessive vibrations in civil engineering. However, due to the absence of the compact dimension, there are still no practical applications of the tuned mass dampers in automotive industry. Meanwhile, recent investigations showed the benefit of utilizing a tuned mass damper in a vehicle suspension in terms of driving comfort and road holding. Thus, the current investigation aimed to explore a novel compact dimension tuned mass damper, which can provide both sufficient vibration mitigation and energy harvesting. This paper presents a prototype of a back-iron-based design of an electromagnetic regenerative tuned mass damper. The mathematical model of the tuned mass damper system was developed and has been validated by the experimental results of the tuned mass damper prototype implemented in a protected mass test-bench. The indicated results concluded that the attenuation performance dramatically deteriorated under random excitations and a reduction in the root-mean-square acceleration of 18% is concluded compared to the case with undamped tuned mass damper. Under harmonic excitations, the designed tuned mass damper prototype is able to reduce the peak acceleration value of the protected structure by 79%. According to the experimental results, the designed tuned mass damper prototype revealed a peak regenerative power of 0.76 W under a harmonic excitation of 8.1 Hz frequency [Formula: see text]m amplitude. Given the simulated random road profiles from C to E, the back-iron electromagnetic tuned mass damper indicated that root-mean-square harvested power from 0.6 to 6.4 W, respectively.


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