This thesis presents some approaches for guided wave based stress monitoring as a part of Structural Health Monitoring (SHM). SHM systems include different levels, from damage detection to prognosis, however, this work is focused on detection and on an estimation of the actual stress. The proposed stress monitoring strategies are based on different statistical and signal processing approaches such as Principal Component Analysis and Residuals. These techniques are applied on signals of elastic guided waves generated and sensed via Piezoelectrical (PZT) or Magnetostrictive transducers. Transducer devices are chosen in this work to generate longitudinal, flexural and torsional guided waves in cylindrical specimens, since their high performance, low energy consumption, weight and reasonable price. In order to guarantee the efficacy of the proposed techniques, they are tested in laboratory by emulating real installations and abnormal conditions. Experimental tests revealed that temperature and bonding layer between the PZT and the specimen influence on the performance of the monitoring scheme by changes in the guided wave propagation. Thus, the temperature effect on guided wave propagation was examined by checking the sensitivity of the PCA-based proposed approach. Then, a temperature compensation strategy is applied to improve stability and robustness of the scheme for structures subjected temperature changes. On the other hand, since the acoustoelasticity effect is predominant in the propagation of stressed guided waves, it was observed its incidence on the dispersion curves by using a SAFE method (Semi-Analytical Finite Element) to generate stressed dispersion curves via Effective Elastic Constants (EEC). Finally, as a consequence of some observations in the experimentation stage, it is proposed a scheme for monitoring the supports rigidity in pipelines based on a guided waves energy leakage perspective. The proposed approaches may promise the ability and capability of being implemented in different fields such as aerospace and gas/oil industry.

Understanding and analysing the complex phenomena related to elastic wave propagation has been the subject of intense research for many years and has enabled application in numerous fields of technology, including structural health monitoring (SHM). In the course of the rapid advancement of diagnostic methods utilising elastic wave propagation, it has become clear that existing methods of elastic wave modeling and analysis are not always very useful; developing numerical methods aimed at modeling and analysing these phenomena has become a necessity. Furthermore, any methods developed need to be verified experimentally, which has become achievable with the advancement of measurement methods utilising laser vibrometry. Guided Waves in Structures for SHM reports on the simulation, analysis and experimental investigation related propagation of elastic waves in isotropic or laminated structures. The full spectrum of theoretical and practical issues associated with propagation of elastic waves is presented and discussed in this one study. Key features: Covers both numerical and experimental aspects of modeling, analysis and measurement of elastic wave propagation in structural elements formed from isotropic or composite materials Comprehensively discusses the application of the Spectral Finite Element Method for modelling and analysing elastic wave propagation in diverse structural elements Presents results of experimental measurements employing advanced laser technologies, validating the quality and correctness of the developed numerical models Accompanying website (www.wiley.com/go/ostachowicz) contains demonstration versions of commercial software developed by the authors for modelling and analyzing elastic wave propagation using the Spectral Finite Element Method Guided Waves in Structures for SHM provides a state of the art resource for researchers and graduate students in structural health monitoring, signal processing and structural dynamics. This book should also provide a useful reference for practising engineers within structural health monitoring and non-destructive testing.

Structural Health Monitoring and Integrity Management is a collection of the papers presented at the 2nd International Conference of Structural Health Monitoring and Integrity Management (ICSHMIM2014, Nanjing, China, 24-26 September 2014), and addresses the most recent developments in the field of Structural Health Monitoring (SHM) and integrity ma

Ultrasonic guided waves in solid media are important in nondestructive testing and structural health monitoring, as new faster, more sensitive, and economical ways of looking at materials and structures have become possible. This book can be read by managers from a "black box" point of view, or used as a professional reference or textbook.

Structural Health Monitoring with Piezoelectric Wafer Active Sensors, Second Edition provides an authoritative theoretical and experimental guide to this fast-paced, interdisciplinary area with exciting applications across a range of industries. The book begins with a detailed yet digestible consolidation of the fundamental theory relating to structural health monitoring (SHM). Coverage of fracture and failure basics, relevant piezoelectric material properties, vibration modes in different structures, and different wave types provide all the background needed to understand SHM and apply it to real-world structural challenges. Moving from theory to experimental practice, the book then provides the most comprehensive coverage available on using piezoelectric wafer active sensors (PWAS) to detect and quantify damage in structures. Updates to this edition include circular and straight-crested Lamb waves from first principle, and the interaction between PWAS and Lamb waves in 1-D and 2-D geometries. Effective shear stress is described, and tuning expressions between PWAS and Lamb waves has been extended to cover axisymmetric geometries with a complete Hankel-transform-based derivation. New chapters have been added including hands-on SHM case studies of PWAS stress, strain, vibration, and wave sensing applications, along with new sections covering essential aspects of vibration and wave propagation in axisymmetric geometries. - Comprehensive coverage of underlying theory such as piezoelectricity, vibration, and wave propagation alongside experimental techniques - Includes step-by-step guidance on the use of piezoelectric wafer active sensors (PWAS) to detect and quantify damage in structures, including clear information on how to interpret sensor signal patterns - Updates to this edition include a new chapter on composites and new sections on advances in vibration and wave theory, bringing this established reference in line with the cutting edge in this emerging area

Stress, Vibration, and Wave Analysis in Aerospace Composites: SHM and NDE Applications presents a unified approach to studying and understanding stress, vibrations and waves in composite materials used in aerospace applications. Combining topics that are typically found across an array of various sources, the book starts by looking at the properties of various composite materials, progresses to coverage of an analysis of stress, vibration and waves and then concludes with a discussion of various structural health monitoring (SHM) and nondestructive evaluation (NDE) techniques and applications based on the analysis developed earlier in the book. Every chapter of the book contains a variety of worked-out examples to illustrate and tie together underlying theory and specific applications. The MATLAB code used to generate these examples is available on the book's companion website, as are solution documents and additional MATLAB code for problems and exercises featured in each chapter. - Presents a comprehensive treatment of aerospace composites, starting with composite material properties and then covering an analysis of stress, vibration and waves, and culminating with SHM and NDE applications - Provides an understanding of the use and application of stress, vibration and waves to detect composite damage and monitor growth - Features an array of worked-out examples, problems and exercises - Includes access to a companion website that features MATLAB codes for worked-out examples, along with problems, exercises and their solutions

A critical review of key developments and latest advances in Structural Health Monitoring technologies applied to civil engineering structures, covering all aspects required for practical application Structural Health Monitoring (SHM) provides the facilities for in-service monitoring of structural performance and damage assessment, and is a key element of condition based maintenance and damage prognosis. This comprehensive book brings readers up to date on the most important changes and advancements in the structural health monitoring technologies applied to civil engineering structures. It covers all aspects required for such monitoring in the field, including sensors and networks, data acquisition and processing, damage detection techniques and damage prognostics techniques. The book also includes a number of case studies showing how the techniques can be applied in the development of sustainable and resilient civil infrastructure systems. Structural Health Monitoring of Large Civil Engineering Structures offers in-depth chapter coverage of: Sensors and Sensing Technology for Structural Monitoring; Data Acquisition, Transmission, and Management; Structural Damage Identification Techniques; Modal Analysis of Civil Engineering Structures; Finite Element Model Updating; Vibration Based Damage Identification Methods; Model Based Damage Assessment Methods; Monitoring Based Reliability Analysis and Damage Prognosis; and Applications of SHM Strategies to Large Civil Structures. Presents state-of-the-art SHM technologies allowing asset managers to evaluate structural performance and make rational decisions Covers all aspects required for the practical application of SHM Includes case studies that show how the techniques can be applied in practice Structural Health Monitoring of Large Civil Engineering Structures is an ideal book for practicing civil engineers, academics and postgraduate students studying civil and structural engineering.

The book presents recent advances regarding the inspection and monitoring of engineering structures; including bridges, buildings, aircraft and space structures, nuclear reactors and defense platforms. Among the techniques covered are UAV photogrammetry, strain monitoring, infrared detection, acoustic emission testing, residual stress measurements, fiber optical sensing, thermographic inspection, vibration analysis, piezoelectric sensing and ultrasonic testing. Keywords: Bridges, Buildings, Aircraft Structures, Space Structures, Nuclear Reactors, Defense Platforms, UAV Photogrammetry, Strain Monitoring, Infrared Detection, Acoustic Emission Testing, Residual Stress Measurements, Fiber Optical Sensing, Thermographic Inspection, Vibration Analysis, Piezoelectric Sensing, Ultrasonic Testing, Impact Damage, Anaerobic Reactor Performance, Geomembranes, Ossointegrated Implants, Fatigue Crack Growth, Accelerometer, Nonlinear Cable Bracing, Timber Utility Poles, Steel Pipes, Loosened Bolts on Pipes, IMU-based Motion Capture, CFRP Composites, Maglev Guideway Girder, Cable-Pylon Anchorage, Deep Learning Techniques.