Numerical Analysis and Validation of Irregularity in Moment Frame Structure Due to Varying Location of Tuned Mass Damper

Abstract

Within the construction industry, the number of higher and lighter structures that are adaptable and have a low damping value has been steadily increasing in recent years. Those constructions will simply fail as a result of earthquake and wind-induced structural vibrations. There are a variety of approaches available today to reduce structural vibration, and one of the oldest is the use of dampers. The tuned mass damper is tuned to the structural frequency of the structure if the stiffness and damping values are kept constant. The main goal is to investigate the mass and torsional irregularity in the structure. This study is divided into two phases - first phase involves the investigation and validation of structure having tuned damper with varying location along the height of building. The second phase involves the location of tuned mass damper with the plan projection of the building. Non-Linear Time history analysis is used to identify the behavior of frame elements in the structure based on considered cases using ETABS. The parameters such as displacement was evaluated. The result shows that the dampers should be carefully placed in order to tune the frequency of the structure.

Introduction

I. INTRODUCTION

Alexander and Schilder (2009) proposed the performance of nonlinear tuned mass damper. A two degree of freedom system with a cubic nonlinearity is modeled. The nonlinearity is originated from geometric arrangement of two pairs of springs. One pair helps in providing linear stiffness whereas the other pair rotates as they extend and helps in hardening spring stiffness. Wong et. al. (2008) studied dissipation of seismic energy in inelastic structures with tuned mass dampers. By using the force analogy method, an inelastic structure is modeled which is chosen as the base of plastic energy dissipation analysis in the structure. Energy response reduction after using TMD is also studied by using plastic energy spectra for various levels of structural yielding. Ghosh and Basu (2004) observed the effect of soil structure interaction and concluded that when the soil becomes stiff, it allows the foundation to move relative to the surrounding soil which changes the soil foundation system from that of the fixed base. In such a case a conventional TMD loses its effectiveness in controlling the response of the structure to base excitation. Kwok and Samali (2006) carried out some experimental verifications of both active and passive TMD and compare the results with parametric study which are very useful in selection of optimal TMD parameters.

Lin et. al. (2010) studied the vibration control of seismic structures using semi-active friction multiple tuned mass dampers. In this paper a semi active friction type multiple tuned mass damper (SAF-MTMD) is developed to control vibration in seismic structures A comparison study is made with a passive friction type multiple tuned mass dampers and concluded that SAF-MTMD effectively reduces the seismic motion particularly at a larger intensity. Lourenco et. al. (2009) performed some experimental work taking a pendulum tuned mass damper with advantageous over conventional TMD. They did some simulation study considering the three dimensional behavior of pendulum mass and found that the frequency can be re tuned by changing the cable length. Wirsching and Campbell (1974) solved the problem of optimizing the TMD parameters and the natural frequency and damping ratio attached to the multi-story structure and analyzed the response of the first main mode of the main structure equipped with a TMD under the Earth lateral vibration of Gaussian white noise. Chouw et. al.(2004) studied the behavior of soil structure interaction with tuned mass dampers during near source earthquake at two different places varying the natural frequency of the dampers . They used the ground motions at the stations SCG and NRG of the 1994 Northridge earthquake for their study and concluded that soil structure interaction and ground motion can increase or decrease the effect of TMD. Li et. al. (2003) numerically observed the performance of multiple active-passive tuned mass dampers (MAPTMD) to prevent vibration of single degree of freedom structures subjected to ground acceleration with a uniform distribution of natural frequency.

The MAPTMD generates a controlling force by keeping the displacement and velocity response gain and changing the acceleration response gain. Farghaly and Ahmed (2012) discussed the design and application of TMD Study indicates the response of structure such as story displacements and shear force of columns can be reduced by using TMD especially with a specific arrangement in the model. Luciara Silva Vellar et. al.(2019) in this work, a new methodology for simultaneous optimization of parameters and positions of multiple tuned mass dampers (MTMDs) in buildings subjected to earthquakes is proposed. For illustration purposes, the proposed methodology is applied in a 10-storey building, confirming its effectiveness. Mohsen Khazaei et al. (2020) In this research, the performance of multiple tuned mass dampers (MTMDs) is investigated in L and U-shaped regular and irregular tall steel buildings with 10 and 20 floors, under the near- and far-field records. Nonlinear time history analysis is also applied to evaluate the multiple tuned mass dampers effects on the seismic responses of the structures. B. Islam and R. Ahsan (2012) they used El Centro NS earthquake to develop a computer program and found a higher percentage of reduction on the roof of a ten-story structure using TMD with the application of EVOP. The study shows the effectiveness of present approach in optimization leading to a more feasible selection of TMD parameters.

II. OBJECTIVES OF THE STUDY

This research work has been undertaken with the following objectives:

1. To create a simpler model of a multistory building with identical parameters and to provide it with and without a tuned mass damper at the same time.
2. To conduct dynamic seismic analysis on the modelled structures using scaled recordings of acceleration time histories and compare the results.

III. CONCEPTS OF TUNED MASS DAMPER

A tuned mass damper (TMD) is a passive control device that is attached to a structure and consists of a mass, a spring, and a damper to lower the structure's dynamic response. The damper inertia force, which acts on the structure, dissipates energy. It's been frequently employed in mechanical engineering systems for vibration control. Because of the easy and simple process, numerous theories have recently been applied to reduce vibration in civil engineering constructions. To provide optimum responsiveness, the secondary mass damper's natural frequency is constantly matched to that of the primary structure, so that when that frequency of the structure is excited, the TMD will resonate out of phase with the structural motion. The surplus energy stored in the structure is converted to secondary mass and dissipated as a result of relative motion created between them later. In this study Pendulum tuned mass damper is taken in to account.

A. Pendulum Tuned Mass Damper

The problems associated with the bearings can be eliminated by supporting the mass with cables which allow the system to behave as a pendulum. Figure 1.4 (a) shows a simple pendulum attached to a floor. Movement of the floor excites the pendulum. The relative motion of the pendulum produces a horizontal force that opposes the floor motion. This action can be represented by an equivalent SDOF system that is attached to the floor, as indicated in Figure 1.4 (b).

A. Structural Details

The work is such that the reinforced concrete beams, columns, slabs, infill walls, and stairs were assigned to model G+8 storey building. These structures were designed in a ‘H’ form with plan dimensions of 21.2 m x 28.4 m. According to IS: 1893(Part I):2016, they are loaded with Dead, Live, and Seismic Forces. The time history approach is then used to examine these models for India's seismic zone V (Zone Factor = 0.36). The modelled building's specifications are provided below. With SMRF (Response Reduction Factor, R=5) and Importance Factor (I) =1, a modal damping of 5% is calculated. The performance of the models is recorded using ETABS in order to give a quick overview of the role of tuned mass dampers in earthquake protection.

V. RESULTS AND DISCUSSIONS

To determine story displacement time history analysis in x and y direction are to be done of a building without TMD and also with TMD for a particular mode and graph plotted to compare the reduction in responses for different modes also for different mass ratio peak story displacement are determine and graph also plotted for them to show the effect of mass variation.

Conclusion

The percentage response reduction is maximum to nearer stories where tuned mass damper is installed. It has been seen that the storey deformation in damped structure is less as compared to the conventional building frame. Application of the damper at the centroidal is more effective than at the eccentric location in terms of displacement.

References

[1] Jerome J. Cannor “Introduction to structural motion control” Prentice Hall Pearson Education, Inc., Upper Saddle River, New Jersey 07458, Google books, Online resources www.scribed.com, chapter 4 pp. 217-285. [2] Jerome J. Cannor and S. Laflamme “Structural motion engineering” doi 10.1007/978-3-319-06281-5__5, Springer International Publishing Switzerland 2014, chapter 5 pp 199-277. [3] Pankaj Agrawal and Manish shrikhande “Earthquake resistant design of structures” Eastern economy edition, online resources www.phindia.com, chapter 12 pp. 196-197&296. [4] S.K. Duggal “Earthquake resistant design of structures” Second edition, Oxford University Press, online resource www.oupinheonline.com, chapter 5 pp. 202-203. [5] T. T. Soong and B. F .Spencer JR “Active, Semi active and Hybrid control of structures”. 12 wcee 2000, 2834, pp. 2-5. [6] Islam B. and Ahsan R. (2012). “Optimization of Tuned Mass Damper Parameters Using Evolutionary Operation algorithm” 15 wcee, losboa 2012. [7] Padmabati Sahoo NIT Rourkela Orissa “Experimental and numerical study on tuned mass damper in controlling vibration of frame structure”. Online resources www.ethesis.nitrkl.ac.in, pp. 3-6. [8] IS 1893 (Part I): 2002 Criteria for Earthquake Resistant Design of Structures. Part I General provisions and buildings (Fifth revision). Bureau of Indian Standards, New Delhi. [9] Etabs 2018 documentation. [10] IS 456: (2000) Indian Standard Code of Practice for Plain and Reinforced Concrete, Bureau of Indian Standards, New Delhi. [11] IS 875 (Part I): 1987 Code of Practice for Design Loads (Other than Earthquake) For Building and Structures. [12] IS 875 (Part II): 1987 Code of Practice for Design Loads (Other than Earthquake) For Building and Structures. [13] Lin, Chi-Chang, et al. \"Vibration control of seismic structures using semi-active friction multiple tuned mass dampers.\" Engineering Structures 32.10 (2010): 3404-3417. [14] Lourenco, R. , Roffel , A. J. and Narasimhan 2009 “Adaptive pendulum mass damper for the control of structural vibrations” Cansmart 2009 international workshop smart materials and structures 22 - 23 October 2009, montreal, quebec, Canada.

Copyright

Copyright © 2022 Reena Sahu, Anurag Wahane. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.