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Experimental and Numerical Study on Tuned Mass Damper in Controlling Vibration of Frame

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Experimental and Numerical Study on Tuned Mass Damper in Controlling Vibration of Frame EXPERIMENTAL AND NUMERICAL STUDY ON TUNED MASS DAMPER IN CONTROLLING VIBRATION OF FRAME STRUCTURES A Thesis Submitted in partial fulfillment of the requirements for the award of Degree of MASTER OF TECHNOLOGY In STRUCTURAL ENGINEERING By PADMABATI SAHOO Roll No. 213CE2074 DEPARTMENT OF CIVIL ENGINEERING NATIONAL INSTITUTE OF TECHNOLOGY ROURKELA, ODISHA-769008 2015 EXPERIMENTAL AND NUMERICAL STUDY ON TUNED MASS DAMPER IN CONTROLLING VIBRATION OF FRAME STRUCTURES A Thesis Submitted in partial fulfillment of the requirements for the award of Degree of MASTER OF TECHNOLOGY In STRUCTURAL ENGINEERING By PADMABATI SAHOO Roll No. 213CE2074 Under the guidance of DR. K. C. BISWAL DEPARTMENT OF CIVIL ENGINEERING NATIONAL INSTITUTE OF TECHNOLOGY ROURKELA, ODISHA-769008 2015 NATIONAL INSTITUTE OF TECHNOLOGY ROURKELA CERTIFICATE This is to certify that the thesis entitled, “EXPERIMENTAL AND NUMERICAL STUDY ON TUNED MASS DAMPER IN CONTROLLING VIBRATION OF FRAME STRUCTURES” submitted by Padmabati Sahoo in partial fulfilment of the requirements for the award of Master of Technology Degree in Civil Engineering with specialization in “Structural Engineering” at National Institute of Technology, Rourkela is an authentic work carried out by her under my supervision and guidance. To the best of my knowledge, the matter embodied in this Project review report has not been submitted to any other university/ institute for award of any Degree or Diploma. Date: Prof K.C. Biswal Dept. of Civil Engineering National Institute of Technology, Rourkela-769008 Dedicated to My Parents, and to each and every teacher , who taught us from alphabets to whatever till date. And to friends who have been there for us from genesis to apocalypse. ACKNOWLEDGEMENT I am obliged to the Dept. of Civil Engineering, NIT ROURKELA, for giving me the opportunity to carry out this project, which is an integral part of the curriculum in M. Tech program at the National Institute of Technology, Rourkela. I would like to articulate my profound gratitude and indebtedness to my project guide Prof.K.C.Biswal, for introducing the present topic and for their inspiring guidance, constructive criticism and valuable suggestion throughout this project work. I sincerely thank to our Director Prof. S. K. Sarangi, HOD of civil engineering department Prof. S. K. Sahu and all the authorities of the institute for providing nice academic environment and other facility in the NIT campus. I express my sincere thanks to Mr. Debadatta Jena and Sandeep for all their help. I am also thankful to Lugun Bhaina and all the staff members of Structural engineering Laboratory, for their assistance and co-operation during the course of experimental works. I also thank all my batch mates who have directly or indirectly helped me in my project work and shared the moments of joy and sorrow throughout the period of project work. Finally, I would like to thank my Parents, who taught me the value of hard work by their own example. I am deeply honored to present this thesis to this department and thank them for their patience and support. PADMABATI SAHOO i ABSTRACT Day by day, the numbers of taller and lighter structures are continuously increasing in the construction industries which are flexible and having a very low damping value. Those structures can easily fail under structural vibrations induced by earthquake and wind. Therefore several techniques are available today to minimize the vibration of the structure, out of which concept of using TMD is a newer one. There are large numbers of studies on theoretical investigation of behaviour of buildings with tuned mass dampers under various impacts. However, the experimental studies in this area are quite limited. In this thesis, a one-storey and a two-storey building frame models are developed for shake table experiment under sinusoidal excitation to observe the response of the structure with and without TMD. The TMD is tuned to the structural frequency of the structure keeping the stiffness and damping constant. Various parameters such as frequency ratio, mass ratio, tuning ratio etc. are considered to observe the effectiveness and robustness of the TMD in terms of percentage reduction in amplitude of the structure. Then the responses obtained are validated numerically using finite element method. From the study it is observed that, TMD can be effectively used for vibration control of structures. ii TABLE OF CONTENTS Contents ACKNOWLEDGEMENT ............................................................................................................... i ABSTRACT .................................................................................................................................... ii LIST OF FIGURES ........................................................................................................................ v LIST OF TABLES ....................................................................................................................... viii 1. INTRODUCTION .................................................................................................................. 1 1.1 Introduction: ..................................................................................................................... 1 1.1.1 Active control devices: ............................................................................................. 1 1.1.2. Passive control devices: ................................................................................................ 2 1.1.3. Semi-active control devices: ......................................................................................... 2 1.1.4. Hybrid control Devices: ................................................................................................ 2 1.2. Tuned mass damper: ............................................................................................................ 3 1.3. Practical implementation: .................................................................................................... 3 2. LITERATURE REVIEW ....................................................................................................... 7 2.1. Literature Review: ............................................................................................................... 7 2.2. Objective and scope of present work: ................................................................................ 12 3. METHODOLOGY ............................................................................................................... 13 3.1. Forced vibration analysis of a physical model:.................................................................. 13 3.2. Solution of forced vibration analysis by Newmark-Beta method: ..................................... 15 3.3. Step-by-step solution using Newmark integration method:............................................... 15 4. EXPERIMENTAL STUDY.................................................................................................. 17 4.1. Introduction: ....................................................................................................................... 17 4.2. Experimental set up: .......................................................................................................... 19 4.2.1. Unidirectional shake table: ......................................................................................... 20 4.2.2. Vibrating analyzer:...................................................................................................... 20 4.2.3. Accelerometer: ............................................................................................................ 20 4.2.4. Control panel:.............................................................................................................. 21 4.2.5. TMD structure model:................................................................................................. 21 4.3. Time-domain analysis for single storey frame: ................................................................. 23 4.3.1 Beating effect in structure mass damper system: ......................................................... 25 4.4. Frequency domain analysis for single storey frame: ......................................................... 27 iii 4.4.1 Effect of frequency ratio on structural amplitude response: ........................................ 28 4.4.2 Effect of mass ratio on structural response for single storey frame:............................ 32 4.4.3. Effect of tuning ratio on structural response for single storey frame: ........................ 33 4.5. Analysis of double storey frame: ....................................................................................... 35 4.6. Frequency domain analysis for double storey frame: ........................................................ 36 4.6.1 Effect of frequency ratio on displacement response: ................................................... 36 4.6.2. Effect of mass ratio on structural response of a double storey frame model: ............. 38 5. NUMERICAL STUDY ........................................................................................................ 40 5.1 Problem statement-1 ........................................................................................................... 40 5.2 Problem statement-2 ........................................................................................................... 45 5.3. Problem statement-3 .........................................................................................................
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