Entropy Based Fatigue, Fracture, Failure Prediction and Structural Health Monitoring


Book Description

Traditionally fatigue, fracture, damage mechanics are predictions are based on empirical curve fitting models based on experimental data. However, when entropy is used as the metric for degradation of the material, the modeling process becomes physics based rather than empirical modeling. Because, entropy generation in a material can be calculated from the fundamental equation of thematerial. This collection of manuscripts is about using entropy for "Fatigue, Fracture, Failure Prediction and Structural Health Monitoring". The theoretical paper in the collection provides the mathematical and physics framework behind the unified mechanics theory, which unifies universal laws of motion of Newton and laws of thermodynamics at ab-initio level. Unified Mechanics introduces an additional axis called, Thermodynamic State Index axis which is linearly independent from Newtonian space x, y, z and time. As a result, derivative of displacement with respect to entropy is not zero, in unified mechanics theory, as in Newtonian mechanics. Any material is treated as a thermodynamic system and fundamental equation of the material is derived. Fundamental equation defines entropy generation rate in the system. Experimental papers in the collection prove validity of using entropy as a stable metric for Fatigue, Fracture, Failure Prediction and Structural Health Monitoring.




Durability of Carbon Fiber Reinforced Plastics


Book Description

Koyanagi presents a concise and practical guide to using a micromechanics approach to predict the strength and durability of unidirectionally aligned continuum carbon fiber reinforced plastics (CFRPs). As the use of composite materials in becomes more widespread in various fields, material durability is becoming an increasingly important consideration, particularly with regard to UN Sustainable Development Goals. Using more durable composite materials would help with achieving these goals. Because the failure of composite materials proceeds via the accumulation of micro failures and micro damage, a micromechanics approach is indispensable for estimating precise durability. In this practical guide, Koyanagi describes this approach and explains the precise durability of the composite materials with regard to the time dependence of micro failures. This book first explains the strength and durability of unidirectionally aligned continuum CFRPs. It then individually addresses fiber, resin, and the interface between the two on the basis of their micromechanics and introduces these components’ time and temperature dependences. Koyanagi uses finite element analysis and theoretical models to integrate the characteristics of the three components to explain the macro properties of the CFRPs. Various characteristics regarding strength and durability of CFRPs are also presented. This book is a valuable resource for researchers in academia and industry who work with composite materials. It will enable them to design composite structures, ensure their durability, evaluate them, and develop more durable composite materials.




Introduction to Thermodynamics of Mechanical Fatigue


Book Description

Fatigue is probabilistic in nature and involves a complex spectrum of loading history with variable amplitudes and frequencies. Yet most available fatigue failure prediction methods are empirical and concentrate on very specific types of loading. Taking a different approach, Introduction to Thermodynamics of Mechanical Fatigue examines the treatment of fatigue via the principles of thermodynamics. It starts from the premise that fatigue is a dissipative process and must obey the laws of thermodynamics. In general, it can be hypothesized that mechanical degradation is a consequence of irreversible thermodynamic processes. This suggests that entropy generation offers a natural measure of degradation. An Entropic Approach to Fatigue and Degradation Drawing on recent cutting-edge research and development, the authors present a unified entropic approach to problems involving fatigue. They introduce the fundamentals of fatigue processes and explore a wide range of practical engineering applications. Fundamental Concepts and Methodologies The book reviews commonly observed failure modes, discusses how to analyze fatigue problems, and examines the deformation characteristics of a solid material subjected to fatigue loading. It also looks at how to use thermodynamics to determine the onset of fatigue failure. In addition, the book presents methodologies for improving fatigue life and for accelerated fatigue testing. Learn How to Apply the Entropic Approach to Fatigue Problems Comprehensive and well organized, this work helps readers apply powerful thermodynamics concepts to effectively treat fatigue problems at the design stage. It offers an accessible introduction to a new and exciting area of research in the field of fatigue failure analysis.




Structural Health Monitoring 2006


Book Description

These proceedings of the Third European Workshop on Structural Health Monitoring held at the Conference Centre in Granada, Spain, in July of 2006 includes four keynote presentations and 170 technical papers written by an international group of contributors. Papers discuss technology and activities related to damage detection and evaluation in engin




The Physics of Degradation in Engineered Materials and Devices


Book Description

Degradation is apparent in all things and is fundamental to both manufactured and natural objects. It is often described by the second law of thermodynamics, where entropy, a measure of disorder, tends to increase with time in a closed system. Things age! This concise reference work brings together experts and key players engaged in the physics of degradation to present the background science, current thinking and developments in understanding, and gives a detailed account of emerging issues across a selection of engineering applications. The work has been put together to equip the upper level undergraduate student, postgraduate student, as well as the professional engineer and scientist, in the importance of physics of degradation. The aim of The Physics of Degradation in Engineered Materials and Devices is to bridge the gap between published textbooks on the fundamental science of degradation phenomena and published research on the engineering science of actual fabricated materials and devices. A history of the observation and understanding of physics of degradation is presented and the fundamentals and principles of thermodynamics and entropy are extensively discussed. This is the focus of this book, with an extended chapter by Alec Feinberg on equilibrium thermodynamic damage and non-equilibrium thermodynamic damage. It concludes with two particular technologies to give examples of areas of application.




Introduction to Unified Mechanics Theory with Applications


Book Description

This text describes the mathematical formulation and proof of the unified mechanics theory (UMT) which is based on the unification of Newton’s laws and the laws of thermodynamics. It also presents formulations and experimental verifications of the theory for thermal, mechanical, electrical, corrosion, chemical and fatigue loads, and it discusses why the original universal laws of motion proposed by Isaac Newton in 1687 are incomplete. The author provides concrete examples, such as how Newton’s second law, F = ma, gives the initial acceleration of a soccer ball kicked by a player, but does not tell us how and when the ball would come to a stop. Over the course of Introduction to Unified Mechanics Theory, Dr. Basaran illustrates that Newtonian mechanics does not account for the thermodynamic changes happening in a system over its usable lifetime. And in this context, this book explains how to design a system to perform its intended functions safely over its usable life time and predicts the expected lifetime of the system without using empirical models, a process currently done using Newtonian mechanics and empirical degradation/failure/fatigue models which are curve-fit to test data. Written as a textbook suitable for upper-level undergraduate mechanics courses, as well as first year graduate level courses, this book is the result of over 25 years of scientific activity with the contribution of dozens of scientists from around the world including USA, Russia, Ukraine, Belarus, Spain, China, India and U.K.




European Workshop on Structural Health Monitoring


Book Description

This volume gathers the latest advances, innovations, and applications in the field of structural health monitoring (SHM) and more broadly in the fields of smart materials and intelligent systems. The volume covers highly diverse topics, including signal processing, smart sensors, autonomous systems, remote sensing and support, UAV platforms for SHM, Internet of Things, Industry 4.0, and SHM for civil structures and infrastructures. The contributions, which are published after a rigorous international peer-review process, highlight numerous exciting ideas that will spur novel research directions and foster multidisciplinary collaboration among different specialists. The contents of this volume reflect the outcomes of the activities of EWSHM (European Workshop on Structural Health Monitoring) in 2020.




Structural Integrity Cases in Mechanical and Civil Engineering


Book Description

This book covers most of the damage mechanism in the scope of mechanical engineering and civil engineering. The failure pattern of various materials and structures is mainly discussed. The sub-topics covers fatigue damage, fatigue crack initiation and propagation, life prediction techniques, computational fracture mechanics, dynamic fracture, damage mechanics and assessment, non-destructive test (NDT), concrete failure assessment, failure on soil structures, structural durability and reliability, structural health monitoring, construction damage recovery, and any relevant topics related to failure analysis.




Thin-Walled Composite Protective Structures for Crashworthiness Applications


Book Description

This book summarizes many of the recent advances in the design and application of thin-walled composite protective structures. The past few decades have seen outstanding advances in the use of composite materials in structural applications. Composites have revolutionized traditional design concepts and made possible an unparalleled range of new and exciting possibilities as viable materials for construction. This book presents an extensive survey on recent improvements in the research and development of composites and biocomposites that are used to make structures in various applications. This book deals with design, research and development studies, experimental investigations, theoretical analysis, and fabrication techniques relevant to the application of composites in load-bearing components for assemblies, ranging from individual components such as plates and shells to complete composite structures. This book also focuses the recent advances in biocomposite materials from renewable resources and introduces a potential application of this material. The content is this book benefits the academics, researchers, scientists, engineers, and students in the field of epoxy blends for application as lightweight advanced composite structures.




Acoustic Emission Signal Analysis and Damage Mode Identification of Composite Wind Turbine Blades


Book Description

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