This detail-oriented text is intended for engineers and applied mathematicians who must write computer programs to perform wavelet and related analysis on real data. It contains an overview of mathematical prerequisites and proceeds to describe hands-on programming techniques to implement special programs for signal analysis and other applications.
Fracture, Fatigue, Failure and Damage Evolution, Volume 7 of the Proceedings of the 2017 SEM Annual Conference & Exposition on Experimental and Applied Mechanics, the seventh volume of nine from the Conference, brings together contributions to this important area of research and engineering. Session organizers include: Jay Carroll, Shuman Xia, Allison Beese, Ryan Berke, Garrett Pataky, Samantha Daly, Kavan Hazeli, Antonios Kontsos, Omer Ozgur Capraz, Scott Grutzik, Onome Scott-Emaukpor The collection presents early findings and case studies on a wide range of areas, including: Mechanics of Energy & Energetic Materials Vibration Effects in Fracture & Fatigue Fracture & Fatigue of Additively Manufactured Materials In Situ Techniques for Fatigue & Fracture Microscale & Microstructural Effects on Mechanical Behavior Fracture & Fatigue of Composites Integration & Validation of Models with Experiments Fracture & Fatigue in Extreme Environments Novel Experimental Methods for Fatigue and Fracture Fracture of Brittle & Ductile Materials Interfacial Fracture
Acoustic Emission Signal Analysis and Damage Mode Identification of Composite Wind Turbine Blades covers both the underlying theory and various techniques for effective structural monitoring of composite wind turbine blades via acoustic emission signal analysis, helping readers solve critical problems such as noise elimination, defect detection, damage mode identification, and more. Author Pengfei Liu introduces techniques for identifying and analyzing progressive failure under tension, delamination, damage localization, adhesive composite joint failure, and other degradation phenomena, outlining methods such as time-difference, wavelet, machine learning, and more including combined methods. The disadvantages and advantages of using each method are covered as are techniques for different blade-lengths and various blade substructures. Piezoelectric sensors are discussed as is experimental analysis of damage source localization. The book also takes great lengths to let readers know when techniques and concepts discussed can be applied to composite materials and structures beyond just wind turbine blades. - Features fundamental acoustic emission theories and techniques for monitoring the structural integrity of wind turbine blades - Covers sensor arrangements, noise elimination, defect detection, and dominating damage mode identification using acoustic emission techniques - Outlines the wavelet method, the time-difference defect detection method, and damage mode identification techniques using machine learning - Discusses how the techniques covered can be extended and adapted for use in other composite structures under complex loads and in different environments
In this book, two kinds of analysis based on acoustic emission recorded during mechanical tests are investigated. In the first, individual, analysis, acoustic signature of each damage mechanism is characterized. So with a clustering method, AE signals that have similar shapes or similar features can be group together into a cluster. Afterwards, each cluster can be linked with a main damage. The second analysis is based on a global AE analysis, on the investigation of liberated energy, with a view to identify a critical point. So beyond this characteristic point, the criticality can be modeled with a power-law in order to evaluate time to failure.
Acoustic Emission (AE) techniques have been studied in civil engineering for a long time. The techniques are recently going to be more and more applied to practical applications and to be standardized in the codes. This is because the increase of aging structures and disastrous damages due to recent earthquakes urgently demand for maintenance and retrofit of civil structures in service for example. It results in the need for the development of advanced and effective inspection techniques. Thus, AE techniques draw a great attention to diagnostic applications and in material testing. The book covers all levels from the description of AE basics for AE beginners (level of a student) to sophisticated AE algorithms and applications to real large-scale structures as well as the observation of the cracking process in laboratory specimen to study fracture processes.
This open access book presents established methods of structural health monitoring (SHM) and discusses their technological merit in the current aerospace environment. While the aerospace industry aims for weight reduction to improve fuel efficiency, reduce environmental impact, and to decrease maintenance time and operating costs, aircraft structures are often designed and built heavier than required in order to accommodate unpredictable failure. A way to overcome this approach is the use of SHM systems to detect the presence of defects. This book covers all major contemporary aerospace-relevant SHM methods, from the basics of each method to the various defect types that SHM is required to detect to discussion of signal processing developments alongside considerations of aerospace safety requirements. It will be of interest to professionals in industry and academic researchers alike, as well as engineering students. This article/publication is based upon work from COST Action CA18203 (ODIN - http://odin-cost.com/), supported by COST (European Cooperation in Science and Technology). COST (European Cooperation in Science and Technology) is a funding agency for research and innovation networks. Our Actions help connect research initiatives across Europe and enable scientists to grow their ideas by sharing them with their peers. This boosts their research, career and innovation.
Given such advantages as low weight compared to strength and toughness, laminated composites are now used in a wide range of applications. Their increasing use has underlined the need to understand their principal mode of failure, delamination. This important book reviews key research in understanding and preventing delamination.The first part of the book reviews general issues such as the role of fracture mechanics in understanding delamination, design issues and ways of testing delamination resistance. Part two describes techniques for detecting and characterising delamination such as piezoelectric sensors, the use of lamb waves and acoustic emission techniques. The next two sections of the book discuss ways of studying and modelling delamination behaviour. The final part of the book reviews research on delamination behaviour in particular conditions such as shell and sandwich structures, z-pin bridging and resin bonding.With its distinguished editor and international team of contributors, Delamination behaviour of composites is a standard reference for all those researching laminated composites and using them in such diverse applications as microelectronics, aerospace, marine, automotive and civil engineering. - Reviews the role of fracture mechanics in understanding delamination, design issues and ways of testing delamination resistance - Discuss ways of studying and modelling delamination behaviour - A standard reference for all those researching laminated composites
The book presents topical theoretical and experimental studies for developing advanced methods of detecting materials fracture and assessing their structural state using acoustic emission. It introduces new mathematical models characterizing the displacement fields arising from crack-like defects and establishes a new criterion for classifying different types of materials fracture based on specific parameters obtained from wavelet transforms of acoustic emission signals. The book applies this approach to experimental studies in three types of materials—fiber-reinforced composites, dental materials, and hydrogen-embrittled steels.
New and not previously published U.S. and international research on composite and nanocomposite materialsFocus on health monitoring/diagnosis, multifunctionality, self-healing, crashworthiness, integrated computational materials engineering (ICME), and moreApplications to aircraft, armor, bridges, ships, and civil structures This fully searchable CD-ROM contains 270 original research papers on all phases of composite materials, presented by specialists from universities, NASA and private corporations such as Boeing. The document is divided into the following sections: Aviation Safety and Aircraft Structures; Armor and Protection; Multifunctional Composites; Effects of Defects; Out of Autoclave Processing; Sustainable Processing; Design and Manufacturing; Stability and Postbuckling; Crashworthiness; Impact and Dynamic Response; Natural, Biobased and Green; Integrated Computational Materials Engineering (ICME); Structural Optimization; Uncertainty Quantification; NDE and SHM Monitoring; Progressive Damage Modeling; Molecular Modeling; Marine Composites; Simulation Tools; Interlaminar Properties; Civil Structures; Textiles. The CD-ROM displays figures and illustrations in articles in full color along with a title screen and main menu screen. Each user can link to all papers from the Table of Contents and Author Index and also link to papers and front matter by using the global bookmarks which allow navigation of the entire CD-ROM from every article. Search features on the CD-ROM can be by full text including all key words, article title, author name, and session title. The CD-ROM has Autorun feature for Windows 2000 or higher products and can also be used with Macintosh computers. The CD includes the program for Adobe Acrobat Reader with Search 11.0. One year of technical support is included with your purchase of this product.
