Smart Materials in Structural Health Monitoring,Control and Biomechanics

Smart Materials in Structural Health Monitoring,Control and Biomechanics, detailed contents

1 Introduction
1.1 Overview
1.2 Concept of Smart Systems/Structures for SHM
1.3 Smart Materials
1.4 Piezoelectricity and Piezoelectric Materials
References
2 Electro-Mechanical Impedance Technique
2.1 Introduction
2.2 Mechanical Impedance of Structures
2.3 Impedance Modeling for EMI Technique
2.4 Mechanical Impedance of PZT Patches
2.5 PZT-Structure Interaction
2.6 Practical Aspects of EMI Technique
2.7 Signal Processing Techniques and Conventional Damage Quantification
2.8 Major Technological Developments During the Last One and a Half Decades
2.9 Advantages of EMI Technique
2.10 Limitations of EMI Technique
References
Exercise 2.1
3 Impedance Models for Structural Health Monitoring Using Piezo-Impedance Transducers
3.1 Introduction
3.2 Early PZT-Structure Interaction Models
3.3 2D Effective Mechanical Impedance
3.4 2D Formulation Based on Effective Impedance
3.5 Experimental Verification
3.5.1 Details of Experimental Set-up
3.5.2 Determination of Structural EDP Impedance by FEM
3.5.3 Modeling of Structural Damping
3.5.4 Wavelength Analysis and Convergence Test
3.5.5 Comparison between Theoretical and Experimental Signatures
3.6 Refining the 2D Impedance Model
3.7 3D Interaction of PZT Transducer with Host Structure
3.7.1 Necessity of 3D Formulation
3.7.2 Issues in 1D and 2D Impedance Models
3.7.3 Issues to Consider in 3D Impedance Model
3.8 3D Model in Presence of Thick Adhesive Bonding
3.8.1 Impedance Formulation
3.8.2 Stress-Strain Relationship of PZT Patch Subjected to 3D Loading
3.8.3 3D Differential Equations
3.8.4 Solution to 3D Differential Equations
3.8.5 Active Part of Solution
3.8.6 Stress-Strain Relationships in Presence of Electric Fields
3.8.7 Formulation of Structural Responses and Impedances
3.8.8 EM Admittance Formulation for M-Functioning PZT Patches
3.8.9 Modifications of Linear Impedance Formulations for Case Studies
3.8.10 Results and Discussions
3.9 FE Modeling of EMI Technique Using Coupled Field Element
3.9.1 Review on FE Modeling of PZT-Structure Interaction
3.9.2 Inclusion of Induced Strain Actuator in FE Model
3.9.3 Comparison of FE Model with Existing Impedance-Based Analytical Model and Experimental Tests
3.9.4 FE Modeling of PZT-Structure Interaction
References
Exercise 3.1
Exercise 3.2
Exercise 3.3
Damage Quantification Using EMI Technique
4.1 Extraction of Structural Mechanical Impedance from Admittance Signatures
4.2 System Parameter Identification from Extracted Impedance Spectra 132
4.3 Damage Diagnosis in Aerospace and Mechanical Systems 137
4.4 Extension to Damage Diagnosis in Civil-Structural Systems 1.44
4.5 Identification of Higher Modal Frequencies from Conductance Signatures 146
4.6 Numerical Example 150
4.7 Experimental Verification 155
4.7.1 Damage Location Identification 158
4.7.2 Effect of Number of Sensitive Modes 159
4.7.3 Effect of Frequency Range 161
4.8 Advantages of Modal Approach 163
4.9 Limitations and Concerns of Modal Approach 163
4.10 Damage Identification Using EMI and Evolutionary Programming 164
4.11 EMI of PZTTransducers 165
4.12 Mechanical Impedance of Damaged Structure 167
4.13 Damage Identification Method 173
4.13.1 EP Algorithm 173
4.13.2 Fitness Function 174
4.14 Experimental Set-up 175
4.15 Experimental Results and Numerical Predictions 177
4.15.1 Damage Identification Results 181
4.15.2 Summary 184
References 184
Exercise 4.1 186
Exercise 4.2 186
5 Strength and Damage Assessment of Concrete 187
5.1 Introduction
5.2 Conventional NDE Techniques for Concrete 187
5.3 Concrete Strength Evaluation Using EMI Technique 190
5.4 Extraction of Damage-Sensitive Concrete Parameters from Admittance Signatures 194
5.5 Monitoring Concrete Curing Using Extracted Impedance Parameters 198
5.6 Establishment of Impedance-Based Damage Model for Concrete 201
5.6.1 Definition of Damage Variable 201
5.6.2 Damage Variable Based on the Theory of Fuzzy Sets 204
5.6.3 Fuzzy Probabilistic Damage Calibration of Piezo-Impedance Transducers 207
5.7 Embedded PZT Patches and Issues Involved 210
5.8 Experimental Set-up
5.8.1 Methods to Fabricate Embeddable PZT
5.8.2 Fabrication of Robust Embeddable PZT Patch
5.9 Efficiency of Embedded PZT
5.9.1 Comparison Test
5.9.2 Monitoring Test
5.10 Damage Analysis Using Statistical Method
References
6 Integration of EMI Technique with Global Vibration Techniques
6.1 Introduction
6.2 Piezoelectric Materials as Dynamic Strain Sensors
6.3 Determination of Strain Mode Shapes Using Surface-Bonded PZT Patches
6.4 Identification and Localization of Incipient Damage
6.5 Localization of Moderate and Severe Damages Using Global Vibration Techniques
6.5.1 For 1D Structures (Beams)
6.5.2 For 2D Structures (Plates)
6.6 Severity of Damage
References
7 Sensing Region, Load Monitoring and Practical Issues
7.1 Sensing Region of PZT Patches
7.1.1 Introduction
7.1.2 Theoretical Modeling
7.1.3 Experimental Verification
7.1.4 Results and Discussions
7.1.5 Summary
7.2 PZT Patches for Load Monitoring
7.2.1 Introduction
7.2.2 Effect of Stress in Structure
7.2.3 Influence of Applied Load on EM Admittance Signatures
7.2.4 Experimental Investigations and Discussions
7.2.5 Efficiency of EM Admittance Signatures Using Statistical Index
7.2.6 Summary
7.3 Practical Issues Related to Application of EMI Technique in SHM
7.3.1 Introduction
7.3.2 Consistency of Admittance Signatures Acquired from PZT Patch
8Smart Beams: A Semi-Analytical Method
9Smart Plates and Shells
10 Cylindrical Shells with Piezoelectric Shear Actuators
11 Fiber Bragg Grating
12 Applications of Fiber Bragg Grating Sensors
13 Monitoring of Rocks and Underground Structures Using PZT and FBG Sensors
14 Ionic Polymer-Metal Composite and its Actuation Characteristics.
15 IPMC-Based Biomedical Applications
16 Bone Characterization Using Piezo-Transducers as Bio-Medical Sensors
17 Future of Smart Materials
Appendix
Index