Su / Ye Identification of Damage Using Lamb Waves

From Fundamentals to Applications
1. Auflage 2009
ISBN: 978-1-84882-784-4
Verlag: Springer
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, Band 48, 355 Seiten

Reihe: Lecture Notes in Applied and Computational Mechanics

Lamb waves are guided waves that propagate in thin plate or shell structures. There has been a clear increase of interest in using Lamb waves for identifying structural damage, entailing intensive research and development in this field over the past two decades. Now on the verge of maturity for diverse engineering applications, this emerging technique serves as an encouraging candidate for facilitating continuous and automated surveillance of the integrity of engineering structures in a cost-effective manner. In comparison with conventional nondestructive evaluation techniques such as ultrasonic scanning and radiography which have been well developed over half a century, damage identification using Lamb waves is in a stage of burgeoning development, presenting a number of technical challenges in application that need to be addressed and circumvented. It is these two aspects that have encouraged us to write this book, with the intention of consolidating the knowledge and know-how in the field of Lamb-wave-based damage identification, and of promoting widespread attention to mature application of this technique in the practical engineering sphere. This book provides a comprehensive description of key facets of damage identification technique using Lamb waves, based on the authors' knowledge, comprehension and experience, ranging from fundamental theory through case studies to engineering applications.

The authors are active researchers in the areas of smart materials and structures. In particular, Prof Ye is an internationally renowned research leader in advanced materials. His major research interests are in the general areas of composites science and technology, intelligent structures, nano-composites, structural integrity and durability. The research team, headed by Prof. Ye, has contributed fruitful achievements to damage identification using active sensor networks. Lin Ye has over 300 scientific publications including 180 refereed papers in leading international journals.

Autoren/Hrsg.

Su, Zhongqing

Ye, Lin

Inhaltsverzeichnis

1;Title Page;2
2;Preface;6
3;Contents;8
4;Introduction;12
4.1;Background;12
4.2;Lamb-wave-based Damage Identification;14
4.3;About this Book;22
4.4;References;23
5;Fundamentals and Analysis of Lamb Waves;26
5.1;Retrospect;26
5.2;Fundamentals and Theory;26
5.2.1;Theory of Lamb Waves;27
5.2.2;Lamb Waves in Plate of Multiple Layers;33
5.2.3;Shear Horizontal Waves and Love Waves;33
5.2.4;Cylindrical Lamb Waves;35
5.2.5;Propagation Velocity – Phase vs. Group Velocities;36
5.2.6;Slowness;37
5.2.7;Dispersion;38
5.3;Numerical and Semi-analytical Study;42
5.3.1;Transfer Matrix Method;44
5.3.2;Global Matrix Method;45
5.4;Finite Element Modelling and Simulation;46
5.4.1;Modelling Lamb Waves;46
5.4.2;Modelling Structural Damage;47
5.5;Attenuation of Lamb Waves;53
5.6;Influence of Temperature;58
5.7;Influence of Damage Orientation and Size;59
5.8;Summary;62
5.9;References;64
6;Activating and Receiving Lamb Waves;70
6.1;Introduction;70
6.2;Transducers of Lamb Waves;70
6.2.1;Ultrasonic Probes;70
6.2.2;Piezoelectric Wafers and Piezocomposite Transducers;72
6.2.3;Laser-based Ultrasonics;73
6.2.4;Interdigital Transducers;73
6.2.5;Fibre-optic Sensors – Reception Only;75
6.3;Activation of Desired Diagnostic Lamb Waves;75
6.3.1;Selection of Appropriate Wave Mode;75
6.3.2;Optimal Design of Waveform;80
6.4;Mechanistic Models of Piezoelectric Transducers;83
6.4.1;Various Models;83
6.4.2;Influence of Transducer Shape;84
6.5;Case Study: Activating and Receiving Lamb Waves (Both the S$_{0}$ and A$_{0}$ Modes) in Delaminated Composite Laminates with Surface-bonded PZT Wafers;87
6.5.1;Modelling Coupled PZT Actuator;87
6.5.2;Modelling Coupled PZT Sensor;95
6.5.3;Validation in FEM Simulation;96
6.6;Summary;99
6.7;References;99
7;Sensors and Sensor Networks;110
7.1;Introduction;110
7.2;Piezoelectric Transducer;112
7.2.1;Design of Piezoelectric Actuator and Sensor;113
7.2.2;Surface-mounting vs. Embedding;117
7.3;Fibre-optic Sensor;120
7.3.1;Optical Fibre and Fibre-optic Sensor;120
7.3.2;Fibre Bragg Grating Sensor;121
7.3.3;FBG Sensor for Lamb Wave Collection;123
7.3.4;Surface-mounting vs. Embedding;127
7.3.5;Directivity;128
7.4;Hybrid Piezoelectric Actuator-optic Sensor Unit;130
7.5;Sensor Network;132
7.5.1;Arrangement and Optimisation of Sensor Network;134
7.5.2;Standardised Sensor Network;137
7.5.3;Commercial Sensor Network Techniques;139
7.6;Recent Developments;141
7.6.1;Large-scale Sensor Network;141
7.6.2;Wireless Sensor;142
7.7;Summary;144
7.8;References;145
8;Processing of Lamb Wave Signals;154
8.1;Introduction;154
8.2;Digital Signal Processing;155
8.2.1;Time Domain Analysis;155
8.2.2;Frequency Domain Analysis;163
8.2.3;Joint Time-frequency Domain Analysis;166
8.3;Wavelet Transform;169
8.3.1;Continuous Wavelet Transform;170
8.3.2;Discrete Wavelet Transform;172
8.3.3;Selection of Wavelet Function;175
8.3.4;Extracting Signal Features Using Wavelet Transform;175
8.4;Processing of Lamb Wave Signals;179
8.4.1;Averaging and Normalisation;179
8.4.2;De-noising;181
8.4.3;Feature Extraction and Damage Index;182
8.4.4;Compression;189
8.5;A Signal Processing Approach for Lamb Waves: Digital Damage Fingerprints;192
8.6;Summary;195
8.7;References;197
9;Algorithms for Damage Identification ? Fusion of Signal Features;205
9.1;Introduction;205
9.2;Data Fusion and Damage Identification Algorithms;206
9.2.1;Damage Index;209
9.2.2;Time-of-flight;209
9.2.3;Time Reversal – for Identifying Damage;219
9.2.4;Migration Technique;219
9.2.5;Lamb Wave Tomography;223
9.2.6;Probability-based Diagnostic Imaging;229
9.2.7;Phased-array Beamforming;238
9.2.8;Artificial Intelligence;244
9.3;Architecture and Scheme of Data Fusion;251
9.3.1;Fusion Architecture;251
9.3.2;Fusion Scheme;253
9.4;Summary;256
9.5;References;258
10;Application of Algorithms for Identifying Structural Damage ? Case Studies;265
10.1;Identifying a Notch in a Structural Alloy Beam Using Damage Index;265
10.1.1;Establishment of DI;266
10.1.2;Assessing Changes in Notch Size Using DI;268
10.2;Locating Delamination in a Composite Panel Using Time-of-flight;271
10.3;Hierarchically Locating Multiple Delamination in a Composite Panel Using Time-of-flight;273
10.3.1;Rationale;274
10.3.2;Experimental Validation;275
10.4;Evaluating Multiple Delamination in a Composite Panel Using Probability-based Diagnostic Imaging;278
10.4.1;Establishment of Prior Perceptions from a Sensing Path in Terms of ToF;278
10.4.2;Establishment of Probability of Presence of Damage;278
10.4.3;Fusion of Probabilities for Diagnostic Imaging;281
10.5;Quantitatively Predicting Delamination in Composite Beams Using an Artificial Neural Network;283
10.5.1;Training Data Preparation;283
10.5.2;ANN Training and Experimental Validation;286
10.5.3;Discussion;286
10.6;Quantitatively Estimating Through-thickness Hole and Delamination in Composite Panels Using an Artificial Neural Network;287
10.6.1;Training Data Preparation;287
10.6.2;Parameterised Modelling;290
10.6.3;ANN Training and Experimental Validation;291
10.6.4;Discussion: Influential Issues;293
10.7;Identifying Structural Damage in a Composite Laminate Using Bayesian Inference;302
10.8;Summary;303
10.9;References;303
11;Systems and Engineering Applications;308
11.1;Introduction;308
11.2;System for Implementation;308
11.2.1;Signal Generation Subsystem;310
11.2.2;Data Acquisition Subsystem;310
11.2.3;Central Control/Analysis Unit;311
11.2.4;Calibration of System;311
11.3;Application in Engineering Structures;314
11.3.1;Detection of Corrosion in Pipelines;314
11.3.2;Identification of Damage in Aerospace Structures;322
11.3.3;Evaluation of Integrity of Civil Infrastructure;329
11.4;Summary;333
11.5;References;334
12;Looking Forward;338
12.1;State of the Art;338
12.2;Prospects;340
12.3;References;348
13;Index;350