Table Of ContentSeismic Vibration Control of Frame Structure Using Shape Memory
Alloy
by
Md. Golam Rashed
MASTER OF SCIENCE IN CIVIL ENGINEERING (STRUCTURAL)
Department of Civil Engineering
BANGLADESH UNIVERSITY OF ENGINEERING AND TECHNOLOGY
February, 2013
Seismic Vibration Control of Frame Structure Using Shape Memory
Alloy
by
Md. Golam Rashed
A thesis submitted to the Department of Civil Engineering of Bangladesh University
of Engineering and Technology, Dhaka, in partial fulfilment of the requirements for
the degree of
MASTER OF SCIENCE IN CIVIL ENGINEERING (STRUCTURAL)
February, 2013
The thesis titled “Seismic Vibration Control of Frame Structure Using Shape
Memory Alloy” submitted by Md. Golam Rashed, Roll No.: 0411042321, Session:
April 2011 has been accepted as satisfactory in partial fulfilment of the requirement
for the degree of M.Sc. Engineering (Civil and Structural) on 25th February, 2013.
BOARD OF EXAMINERS
______________________________________
Dr. Raquib Ahsan Chairman
Professor (Supervisor)
Department of Civil Engineering
BUET, Dhaka.
______________________________________
Dr. Md. Mujibur Rahman Member
Professor and Head (Ex-officio)
Department of Civil Engineering
BUET, Dhaka.
______________________________________
Dr. Tahsin Reza Hossain Member
Professor
Department of Civil Engineering
BUET, Dhaka.
______________________________________
Dr. Sharmin Reza Chowdhury Member
Associate Professor (External)
Department of Civil Engineering
AUST, Dhaka.
ii
D
ECLARATION
It is hereby declared that this thesis or any part of it has not been submitted elsewhere
for the award of any degree or diploma.
_________________________________
Md. Golam Rashed
iii
D
EDICATION
To my wife, for being patient and understanding.
iv
A
CKNOWLEDGEMENT
At first I would like to express my whole hearted gratitude to Almighty Allah for each
and every achievement of my life.
I would like to express my great respect and gratitude to my thesis supervisor, Dr.
Raquib Ahsan, Professor, Department of Civil Engineering, BUET for providing me
continuous support and guideline to perform this research work and to prepare this
concerted dissertation. His contribution to me can only be acknowledged but never be
compensated. His consistent inspiration helped me to work diligently throughout the
completion of this research work and also contributed to my ability to approach and
solve a problem. It was not easy to complete this work successfully without his
invaluable suggestions and continuous help and encouragement. Despite many
difficulties and limitations he tried his best to support the author in every field related
to this study.
I would like to express my deepest gratitude to the Department of Civil Engineering,
BUET, The Head of the Department of Civil Engineering and all the members of
BPGS committee to give me such a great opportunity of doing my M.Sc. and this
contemporary research work on structural application of Shape Memory Alloy
(SMA).
I would like to render sincere gratitude to Dr. Toby Kim Parnell, USA and Dr. Furo
Jumbo, UK for providing useful knowledge on SMA simulation and advanced FEA. I
am grateful to Dr. Rafiqul A. Tarefder, UNM, USA for providing the experimental
test data and to Dr. Mehedi Ahmed Ansary, BUET, for providing required
computational facilities.
I would like to convey my gratefulness and thanks to my family, their undying love,
encouragement and support throughout my life and education. Without their
blessings, achieving this goal would have been impossible.
At last I would like to thank my respected supervisor Dr. Raquib Ahsan once again
for giving me such an opportunity, which has obviously enhanced my knowledge and
skills as a structural engineer to a great extent.
v
A
BSTRACT
The use of Shape Memory Alloy (SMA) in mitigating the seismic vibration response
of civil infrastructure is gaining momentum. The name “Shape Memory” implies that
it remembers its original formed shape. SMA has two basic properties, Super-
Elasticity and Shape Memory Effect (SME). The “Super-Elastic” behaviour exhibited
by SMA materials, permits a full recovery of strains up to 8% from large cyclic
deformations, while developing a hysteretic loop. SME allows the material to recover
the initial shape or position which in turn can be used as re-centering mechanism. The
mechanism of shape recovery involves two crystallographic phases, Martensite and
Austenite, and the transformations between them. The Austenite phase provides more
stiffness than the Martensite phase. Phase transformation occurs between Martensite
& Austenite depending upon temperature & stress. These unique properties result in
high damping, combined with repeatable re-centering capabilities which can be used
to advantage in several civil infrastructure applications, especially in seismic vibration
control devices.
Super-Elastic response of SMA has historically been the primary mode of interest of
civil engineers as it occurs over a wide-range of temperatures; and also because SMA
reaches activation temperature and becomes Austenite at the ambient temperature of
civil engineering infrastructures. Thus the re-centering capability of SMA by
generation of an activation force is not utilized. The use of high temperature SMA has
enabled the re-centering mechanism to work. The SMA is heated by electrical current
flow and the use of constant current in this purpose will result in greater power
consumption which can be reduced significantly by passing pulsed current through
the SMA using Pulse Width Modulation (PWM) technique.
In this study, both the Super-Elastic and Shape Memory Effect has been taken into
account by using SMA with high activation temperature. A Thermo-Mechanical SMA
phenomenological constitutive model is used to simulate the SMA behaviour. The
dynamic response data of a frame structure has been obtained from FE analysis by
using the nonlinear FE software program MSC Marc. Then the frame is braced and
reanalyzed; first using standard steel wire and then later using SMA wire, the seismic
response of both the braced frames were measured. The SMA bracing is activated by
joule-heating due to electrical current flow. The SMA is first activated by constant
current, later using pulsed current. In this research work, From the FE solutions, the
effectiveness of SMA braces as a seismic vibration control device and guidelines to
optimum electrical input, considering appropriate stiffness and damping
characteristics; is established. From the simulation result, it is evident that the use of
pulsed current resulted in reduced energy consumption by the SMA, as well as
mitigating the seismic vibrations on the frame structure.
vi
C
ONTENTS
Page
No.
DECLARATION iii
DEDICATION iv
ACKNOWLEDGEMENT v
ABSTRACT vi
LIST OF FIGURES x
LIST OF TABLES xvi
LIST OF ABBREVIATIONS xvii
NOTATIONS xviii
CHAPTER 1 INTRODUCTION
1.1 General 19
1.2 Background and Present State of the Problem 20
1.3 Objectives of the Present Study 20
1.4 Scope and Methodology of the Study 21
1.5 Organization of the Thesis 21
CHAPTER 2 LITERATURE REVIEW
2.1 General 23
2.2 Basic Characteristics of SMA’s 25
2.2.1 Shape Memory Effect 27
2.2.2 Pseudo-Elasticity 27
2.2.3 Damping Properties 28
2.3 Constitutive Modeling of Shape Memory Alloys 29
vii
2.3.1 Phenomenological Modeling 29
2.3.2 Thermodynamics-Based Modeling 29
2.4 Structural Applications of SMA in Civil 30
Engineering
2.4.1 SMA in Building Structures 30
2.4.2 SMA in Bridge Structures 32
2.5 Limitations 33
2.6 Concluding Remarks 33
CHAPTER 3 CONSTITUTIVE MODELING
3.1 General 35
3.2 Overview of Constitutive Modeling of Shape 35
Memory Alloys
3.3 Saeedvafa Constitutive Model for Shape 37
Memory Alloy
3.4 Implementation 45
3.5 Concluding Remarks 48
CHAPTER 4 VERIFICATION
4.1 General 49
4.2 Experimental Setup and Geometric Properties 49
4.3 Material Properties 51
4.4 Modeling Assumptions and Analysis Procedure 53
4.5 Verification 58
4.5.1 El Centro Case 59
4.5.2 Northridge Case 61
4.6 Concluding Remarks 63
viii
CHAPTER 5 RESULTS AND DISCUSSIONS
5.1 General 64
5.2 Simulation Parameters and Procedures 64
5.3 Unbraced and Steel Braced Frame Parametric 67
Study
5.4 SMA braced Frame Parametric Study 73
5.4.1 Constant Current 74
5.4.2 Pulsed Current 87
CHAPTER 6 CONCLUSIONS AND
RECOMMENDATIONS
6.1 Conclusions 104
6.2 Recommendations for Further Studies 105
REFERENCES 106
Appendix - A 112
ix
Description:The use of Shape Memory Alloy (SMA) in mitigating the seismic vibration response mitigating the seismic vibrations on the frame structure.
