scholarly journals Analysis of a Benchmark Building Installed with Tuned Mass Dampers under Wind and Earthquake Loads

2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
S. Elias ◽  
R. Rupakhety ◽  
S. Olafsson
Keyword(s):  
Equations Of Motion ◽  
Equal Mass ◽  
Dynamic Responses ◽  
Acceleration Response ◽  
Tuned Mass Dampers ◽  
Response Control ◽  
Earthquake Loads ◽  
Coupled Equations ◽  
Wind Response ◽  
The One

This study presents analysis of a benchmark building installed with tuned mass dampers (TMDs) while subjected to wind and earthquake loads. Different TMD schemes are applied to reduce dynamic responses of the building under wind and earthquakes. The coupled equations of motion are formulated and solved using numerical methods. The uncontrolled building (NC) and the controlled building are subjected to a set of 100 earthquake ground motions and wind forces. The effectiveness of using different multiple TMD (MTMD) schemes as opposed to single TMD (STMD) is presented. Optimal TMD parameters and their location are investigated. For a tall structure like the one studied here, TMDs are found to be more effective in controlling acceleration response than displacement, when subjected to wind forces. It is observed that MTMDs with equal stiffness in each of the TMDs (usually considered for wind response control), when optimized for a given structure, are effective in controlling acceleration response under both wind and earthquake forces. However, if the device is designed with equal mass in every floor, it is less effective in controlling wind-induced floor acceleration. Therefore, when it comes to multihazard response control, distributed TMDs with equal stiffnesses should be preferred over those with equal masses.

scholarly journals Vibration Suppression of Wind/Traffic/Bridge Coupled System Using Multiple Pounding Tuned Mass Dampers (MPTMD)

Sensors ◽  
2019 ◽  
Vol 19 (5) ◽  
pp. 1133 ◽  
Author(s):  
Xinfeng Yin ◽  
Gangbing Song ◽  
Yang Liu
Keyword(s):  
Vibration Suppression ◽  
Equations Of Motion ◽  
Coupled System ◽  
Highway Bridges ◽  
Dynamic Responses ◽  
Viscoelastic Layer ◽  
Parameter Study ◽  
Mass Ratio ◽  
Tuned Mass Dampers ◽  
Coupled Equations

Dynamic responses of highway bridges induced by wind and stochastic traffic loads usually exceed anticipated values, and tuned mass dampers (TMDs) have been extensively applied to suppress dynamic responses of bridge structures. In this study, a new type of TMD system named pounding tuned mass damper (PTMD) was designed with a combination of a tuned mass and a viscoelastic layer covered delimiter for impact energy dissipation. Comprehensive numerical simulations of the wind/traffic/bridge coupled system with multiple PTMDs (MPTMDs) were performed. The coupled equations were established by combining the equations of motion of both the bridge and vehicles in traffic. For the purpose of comparing the suppressing effectiveness, the parameter study of the different numbers and locations, mass ratio, and pounding stiffness of MPTMDs were studied. The simulations showed that the number of MPTMDs and mass ratio are both significant in suppressing the wind/traffic/bridge coupled vibration; however, the pounding stiffness is not sensitive in suppressing the bridge vibration.

Study on Seismic Response Characteristics of Double Cables Suspension Bridge

2011 ◽  
Vol 105-107 ◽  
pp. 408-411
Author(s):  
Nan Hong Ding ◽  
Li Xia Lin ◽  
Yong Jiu Qian ◽  
Lei Huang
Keyword(s):  
Seismic Response ◽  
Damping Ratio ◽  
Dynamic Performance ◽  
Equations Of Motion ◽  
Suspension Bridge ◽  
Dynamic Responses ◽  
Independent Effect ◽  
Shape Coefficient ◽  
Response Characteristics ◽  
Coupled Equations

Damping in double Cables suspension bridge composed of steel reinforcement beams and reinforced concrete tower is non-classical, which leads to coupled equations of motion in main coordinate system. Based on the complex damping theory, the viscous damping ratio is solved, which can be used to describe energy dissipation characteristics of non-classical damping system approximately. Seismic response of double chains suspension bridge is analyzed through an example of double chains suspension bridge, considering the geometric nonlinearity and non-classical damping. And numerical calculation is presented for seismic response subjected to independent effect or combination effect of three orthogonal components of seismic wave. Single cable suspension bridge can be taken as a special case of double cable suspension bridge, after the main cable shape coefficient is introduced. The dynamic responses of double cable suspension bridge and single cable suspension bridge are compared to reveal the characteristics of Seismic Response of double cable suspension bridge. The study of the dynamic responses characteristics of double cable suspension bridge has a positive significance on structural form selection of such type bridge during designing, dynamic performance evaluation and reinforcement design has positive significance.

scholarly journals Distributed Multiple Tuned Mass Dampers for Wind Vibration Response Control of High-Rise Building

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Said Elias ◽  
Vasant Matsagar
Keyword(s):  
Equations Of Motion ◽  
Vibration Response ◽  
Mode Shapes ◽  
Tuned Mass Dampers ◽  
Response Control ◽  
High Rise ◽  
High Rise Building ◽  
Wind Vibration ◽  
Wind Induced Vibration ◽  
Multiple Tuned Mass Dampers

Multiple tuned mass dampers (MTMDs) distributed along height of a high-rise building are investigated for their effectiveness in vibration response control. A 76-storey benchmark building is modeled as shear type structure with a lateral degree of freedom at each floor, and tuned mass dampers (TMDs) are installed at top/different floors. Suitable locations for installing the TMDs and their tuning frequencies are identified based, respectively, on the mode shapes and frequencies of the uncontrolled and controlled buildings. Multimode control strategy has been adopted, wherein each TMD is placed where the mode shape amplitude of the building is the largest or large in the particular mode being controlled and tuned with the corresponding modal frequency. Newmark’s method is used to solve the governing equations of motion for the structure. The performance of the distributed MTMDs (d-MTMDs) is compared with single tuned mass damper (STMD) and all the MTMDs placed at top floor. The variations of top floor acceleration and displacement under wind loads are computed to study the effectiveness of the MTMDs in vibration control of the high-rise building. It is concluded that the d-MTMDs are more effective to control wind induced vibration than the STMD and the MTMDs placed at top floor.

Dynamic Response Control of a Wind-Excited Tall Building with Distributed Multiple Tuned Mass Dampers

2019 ◽  
Vol 19 (06) ◽  
pp. 1950059 ◽  
Author(s):  
Said Elias ◽  
Vasant Matsagar ◽  
T. K. Datta
Keyword(s):  
Dynamic Response ◽  
Equations Of Motion ◽  
Tall Building ◽  
Mode Shapes ◽  
Induced Response ◽  
Tuned Mass Dampers ◽  
Response Control ◽  
Modal Amplitude ◽  
Improved Performance ◽  
Multiple Tuned Mass Dampers

Dynamic response control of a wind-excited tall building installed with distributed multiple tuned mass dampers (d-MTMDs) is presented. The performance of d-MTMDs is compared with those of single tuned mass damper (STMD) and MTMDs installed at top of the building. The modal frequencies and mode shapes of the building are first determined. Based on the mode shapes of the uncontrolled and controlled building, the most suitable locations are identified for the dampers, in that the TMDs are placed where the modal amplitude of the building is the largest/larger in a particular mode, with each tuned to the modal frequency of the first five modes. The coupled differential equations of motion for the system are derived for the cases with the STMD, MTMDs, and d-MTMDs and solved numerically. Extensive parametric studies are conducted to compare the effectiveness of the three control schemes using STMD, MTMDs, and d-MTMDs by examining the variations in wind-induced responses. The mass ratios, damping ratios of the devices, number of TMDs, and robustness of the TMDs are the parameters of investigation. It is concluded that the MTMDs exhibit improved performance when compared with the STMD. The use of d-MTMDs is most efficient among the three schemes because it can effectively control wind-induced response of the building, while reduced space is required in the installation of the TMDs, as they are placed at various floors.

Analytical and Experimental Investigation of the Coupled Bladed Disk/Shaft Whirl of a Cantilevered Turbofan

1986 ◽  
Vol 108 (4) ◽  
pp. 567-575 ◽  
Author(s):  
E. F. Crawley ◽  
E. H. Ducharme ◽  
D. R. Mokadam
Keyword(s):  
Analytical Model ◽  
Natural Frequencies ◽  
Equations Of Motion ◽  
Disk System ◽  
Structural Dynamic ◽  
Nodal Diameter ◽  
Coupled Equations ◽  
Bladed Disk ◽  
Shaft System ◽  
The One

The structural dynamics of a rotating flexible blade-rigid disk-flexible cantilevered shaft system is analytically and experimentally investigated. A simple analytical model yields the equations of motion expressed in the rotating frame, which show that the blade one nodal diameter modes dynamically couple to the rigid body whirling motion of the shaft-disk system. The blade modes higher than one nodal diameter are uncoupled from the shaft-disk dynamics. Nondimensionalization of the coupled equations of motion yield the criteria for the propensity and magnitude of the interaction between the bladed disk and shaft-disk modes. The analytical model was then correlated with the results of a structural dynamic experiment performed on the MIT Aeroelastic Rotor, a fan similar in design to a modern high bypass ratio shroudless turbofan. A special whirl excitation apparatus was used to excite both forward and backward asynchronous whirl, in order to determine the natural frequencies of the system. The agreement between the predicted and experimental natural frequencies is good and indicates the possibility of significant interaction of the one nodal diameter blade modes with the shaft-disk modes.

Tuned mass dampers in wind response control of wind turbine with soil-structure interaction

2020 ◽  
Vol 132 ◽  
pp. 106071 ◽  
Author(s):  
Shashwat Gaur ◽  
Said Elias ◽  
Thomas Höbbel ◽  
Vasant A. Matsagar ◽  
Klaus Thiele
Keyword(s):  
Wind Turbine ◽  
Soil Structure ◽  
Soil Structure Interaction ◽  
Tuned Mass Dampers ◽  
Response Control ◽  
Structure Interaction ◽  
Wind Response
Sign in / Sign up

Export Citation Format

Share Document