Download or read book Ultrasonic Stress Measurement for Evaluating the Adequacy of Gusset Plates written by Jason Paul Klemme and published by . This book was released on 2012 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: A significant challenge in determining the safety margin for gusset plates is determining the level of stresses carried in the plate. Present technologies are unable to evaluate the dead, live and residual stresses maintained in gusset plates. The goal of the research presented in this thesis is to improve the safety of highway bridges by developing and testing an ultrasonic stress measurement methodology for determining actual stress in steel gusset plates, evaluating the accuracy and precision of the measurements, and assess if the methodology has sufficient accuracy and precision to be a useful tool in the safety analysis of gusset plates. This research utilizes the acoustoelastic effect to evaluate actual stress levels by assessing the acoustic birefringence in a steel material. The birefringence measurement evaluates normalized variations of polarized shear waves propagating through the plate thickness, which vary proportionally as a function of stress. This thesis discusses exploratory testing to evaluate the potential of the approach as a tool for the condition assessment of gusset plates.
Download or read book Ultrasonic Biaxial Stress Measurement for Evaluating the Adequacy of Gusset Plates written by Steven Brooks (Engineer) and published by . This book was released on 2014 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: The collapse of the I-35W bridge in Minneapolis, Minnesota, on August 1, 2007, resulted in the deaths of 13 people. In an investigation conducted by the National Transportation Safety Board, the cause of the collapse was determined to be the failure of an overstressed steel gusset plate which connected key members of the structure. Following the collapse, State Departments of Transportation sought to confirm the adequacy of gusset plates in other bridges to ensure overstressed gusset plates were not present. Total stresses in a gusset plate cannot be effectively determined using conventional tools such as strain gages. The goal of this research was to improve the safety of steel truss highway bridges by developing an ultrasonic stress measurement methodology for determining total stress in steel gusset plates. A methodology was developed and assessed based on the results of laboratory testing in which the accuracy and precision of ultrasonic stress measurements for a biaxial stress condition were evaluated. This research utilized the acoustoelastic effect to evaluate total stress levels by assessing the acoustic birefringence in steel. The birefringence measurement evaluates normalized variations of polarized shear waves propagating through the plate thickness; these shear waves vary proportionally as a function of stress. A sine regression technique was applied to measure the desired birefringence parameters. Testing results indicated stress measurement uncertainties of 2,600 psi (12.5% of the shear yield strength) or less. This study demonstrated the potential of the sine regression technique to accurately and repeatedly assess total stress levels in steel gusset plates.
Download or read book Handbook of Steel Connection Design and Details written by Akbar R. Tamboli and published by McGraw Hill Professional. This book was released on 2010 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surveys the leading methods for connecting structural steel components, covering state-of-the-art techniques and materials, and includes new information on welding and connections. Hundreds of detailed examples, photographs, and illustrations are found throughout this handbook. --from publisher description.
Download or read book Recommendations for Fatigue Design of Welded Joints and Components written by A. F. Hobbacher and published by Springer. This book was released on 2015-12-23 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a basis for the design and analysis of welded components that are subjected to fluctuating forces, to avoid failure by fatigue. It is also a valuable resource for those on boards or commissions who are establishing fatigue design codes. For maximum benefit, readers should already have a working knowledge of the basics of fatigue and fracture mechanics. The purpose of designing a structure taking into consideration the limit state for fatigue damage is to ensure that the performance is satisfactory during the design life and that the survival probability is acceptable. The latter is achieved by the use of appropriate partial safety factors. This document has been prepared as the result of an initiative by Commissions XIII and XV of the International Institute of Welding (IIW).
Download or read book IIW Recommendations On Methods for Improving the Fatigue Strength of Welded Joints written by P J Haagensen and published by Woodhead Publishing. This book was released on 2013-01-25 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: The weld toe is a primary source of fatigue cracking because of the severity of the stress concentration it produces. Weld toe improvement can increase the fatigue strength of new structures significantly. It can also be used to repair or upgrade existing structures. However, in practice there have been wide variations in the actual improvements in fatigue strength achieved. Based on an extensive testing programme organised by the IIW, this report reviews the main methods for weld toe improvement to increase fatigue strength: burr grinding, TIG dressing and hammer and needle peening. The report provides specifications for the practical use of each method, including equipment, weld preparation and operation. It also offers guidance on inspection, quality control and training as well as assessments of fatigue strength and thickness effects possible with each technique. IIW recommendations on methods for improving the fatigue strength of welded joints will allow a more consistent use of these methods and more predictable increases in fatigue strength. Provides specifications for the practical use of each weld toe method, including equipment, weld preparation and operation Offers guidance on inspection, quality control and training, as well as assessments of fatigue strength and thickness effects possible with each technique This report will allow a more consistent use of these methods and more predictable increases in fatigue strength
Download or read book Structural Hot Spot Stress Approach to Fatigue Analysis of Welded Components written by Erkki Niemi and published by Springer. This book was released on 2017-08-28 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides background and guidance on the use of the structural hot-spot stress approach to fatigue analysis. The book also offers Design S-N curves for use with the structural hot-spot stress for a range of weld details, and presents parametric formulas for calculating stress increases due to misalignment and structural discontinuities. Highlighting the extension to structures fabricated from plates and non-tubular sections. The structural hot-spot stress approach focuses on cases of potential fatigue cracking from the weld toe and it has been in use for many years in tubular joints. Following an explanation of the structural hot-spot stress, its definition and its relevance to fatigue, the book describes methods for its determination. It considers stress determination from both finite element analysis and strain gauge measurements, and emphasizes the use of finite element stress analysis, providing guidance on the choice of element type and size for use with either solid or shell elements. Lastly, it illustrates the use of the recommendations in four case studies involving the fatigue assessment of welded structures using the structural hot-spot stress
Download or read book LRFD Guide Specifications for the Design of Pedestrian Bridges written by American Association of State Highway and Transportation Officials and published by AASHTO. This book was released on 2009 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue Assessment of Welded Joints by Local Approaches written by Dieter Radaj and published by Woodhead Publishing. This book was released on 2006-10-30 with total page 661 pages. Available in PDF, EPUB and Kindle. Book excerpt: Local approaches to fatigue assessment are used to predict the structural durability of welded joints, to optimise their design and to evaluate unforeseen joint failures. This standard work provides a systematic survey of the principles and practical applications of the various methods. It covers the hot spot structural stress approach to fatigue in general, the notch stress and notch strain approach to crack initiation and the fracture mechanics approach to crack propagation. Seam-welded and spot-welded joints in structural steels and aluminium alloys are also considered.This completely reworked second edition takes into account the tremendous progress in understanding and applying local approaches which has been achieved in the last decade. It is a standard reference for designers, structural analysts and testing engineers who are responsible for the fatigue-resistant in-service behaviour of welded structures. - Completely reworked second edition of a standard work providing a systematic survey of the principles and practical applications of the various methods - Covers the hot spot structural stress approach to fatigue in general, the notch stress and notch strain approach to crack initiation and the fracture mechanics approach to crack propagation. - Written by a distinguished team of authors
Download or read book Steel Construction Manual written by American Institute of Steel Construction and published by Amer Inst of Steel Construction. This book was released on 2011 with total page 2192 pages. Available in PDF, EPUB and Kindle. Book excerpt: Originally published in 1926 [i.e. 1927] under title: Steel construction; title of 8th ed.: Manual of steel construction.
Download or read book Fatigue Testing and Analysis written by Yung-Li Lee and published by Elsevier. This book was released on 2011-04-18 with total page 417 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue Testing and Analysis: Theory and Practice presents the latest, proven techniques for fatigue data acquisition, data analysis, and test planning and practice. More specifically, it covers the most comprehensive methods to capture the component load, to characterize the scatter of product fatigue resistance and loading, to perform the fatigue damage assessment of a product, and to develop an accelerated life test plan for reliability target demonstration. This book is most useful for test and design engineers in the ground vehicle industry. Fatigue Testing and Analysis introduces the methods to account for variability of loads and statistical fatigue properties that are useful for further probabilistic fatigue analysis. The text incorporates and demonstrates approaches that account for randomness of loading and materials, and covers the applications and demonstrations of both linear and double-linear damage rules. The reader will benefit from summaries of load transducer designs and data acquisition techniques, applications of both linear and non-linear damage rules and methods, and techniques to determine the statistical fatigue properties for the nominal stress-life and the local strain-life methods. - Covers the useful techniques for component load measurement and data acquisition, fatigue properties determination, fatigue analysis, and accelerated life test criteria development, and, most importantly, test plans for reliability demonstrations - Written from a practical point of view, based on the authors' industrial and academic experience in automotive engineering design - Extensive practical examples are used to illustrate the main concepts in all chapters
Download or read book Forensic Engineering written by Alicia Díazde León and published by . This book was released on 2012-11 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the Sixth Congress on Forensic Engineering, held in San Francisco, California, October 31-November 3, 2012. Sponsored by the Technical Council on Forensic Engineering of ASCE. This collection contains 144 peer-reviewed papers presenting findings intended to help forensic engineers develop practices and procedures to reduce the number of failures, disseminate information on failures, and provide guidelines for conducting failure investigations and for ethical conduct. Topics include: bridges; building envelopes; critical infrastructure; design practices; disaster risk management; education; emerging technologies; fires; floods; flooring; geotechnical failures; hurricanes, tornadoes, and extreme winds; investigative methodologies; practices to reduce failures; professional practice; research and testing; residential construction; and structural failures. This will be valuable to engineers, researchers, educators, and students involved in forensic engineering.
Download or read book Extrusion written by Harold F. Giles Jr and published by William Andrew. This book was released on 2013-09-21 with total page 638 pages. Available in PDF, EPUB and Kindle. Book excerpt: The second edition of Extrusion is designed to aid operators, engineers, and managers in extrusion processing in quickly answering practical day-to-day questions. The first part of the book provides the fundamental principles, for operators and engineers, of polymeric materials extrusion processing in single and twin screw extruders. The next section covers advanced topics including troubleshooting, auxiliary equipment, and coextrusion for operators, engineers, and managers. The final part provides applications case studies in key areas for engineers such as compounding, blown film, extrusion blow molding, coating, foam, and reprocessing. This practical guide to extrusion brings together both equipment and materials processing aspects. It covers basic and advanced topics, for reference and training, in thermoplastics processing in the extruder. Detailed reference data are provided on such important operating conditions as temperatures, start-up procedures, shear rates, pressure drops, and safety. - A practical guide to the selection, design and optimization of extrusion processes and equipment - Designed to improve production efficiency and product quality - Focuses on practical fault analysis and troubleshooting techniques
Download or read book Collapsing Structures and Public Mismanagement written by Wolfgang Seibel and published by Springer Nature. This book was released on 2022-01-07 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book is about mismanagement of public agencies as a threat to life and limb. Collapsing bridges and buildings kill people and often leave many more injured. Such disasters do not happen out of the blue nor are they purely technical in nature since construction and maintenance are subject to safety regulation and enforcement by governmental agencies. This book analyses four relevant cases from Australia, New Zealand, the USA and Germany. Arguing that, while preventing disaster through public oversight is essentially easy, the difficult part for public officials and private contractors and consultants alike is to resist incentives that threaten professional skills and standards. Rather than stressing well-known pathologies of bureaucracy as a potential source of disaster, this book argues, learning for the sake of prevention should aim at neutralizing threats to integrity and strengthening a sense of responsibility among public officials.
Download or read book Fatigue Design ESIS 16 written by J. Solin and published by Wiley-Blackwell. This book was released on 1993-03-02 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: A compilation of research in fatigue design, prediction, and assessment Fatigue Design is a collection of research presented at the 1993 International Symposium on Fatigue Design. Detailing the latest findings and most current research, this book features papers on a variety of pertinent topics, including the quantification of service load for fatigue life predictions, identification of stress states and failure modes, assessment of residual life in damaged components, and more. Special attention is paid to the need for simple and reliable prediction tools to help better ensure adequate strength at the design stage.
Download or read book Fatigue and Fracture written by F. C. Campbell and published by ASM International. This book was released on 2012-01-01 with total page 699 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This book emphasizes the physical and practical aspects of fatigue and fracture. It covers mechanical properties of materials, differences between ductile and brittle fractures, fracture mechanics, the basics of fatigue, structural joints, high temperature failures, wear, environmentally-induced failures, and steps in the failure analysis process."--publishers website.
Download or read book Airframe Structural Design written by Chunyun Niu and published by Adaso Adastra Engineering Center. This book was released on 1999 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue of Structures and Materials written by J. Schijve and published by Springer Science & Business Media. This book was released on 2008-12-16 with total page 627 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue of structures and materials covers a wide scope of different topics. The purpose of the present book is to explain these topics, to indicate how they can be analyzed, and how this can contribute to the designing of fatigue resistant structures and to prevent structural fatigue problems in service. Chapter 1 gives a general survey of the topic with brief comments on the signi?cance of the aspects involved. This serves as a kind of a program for the following chapters. The central issues in this book are predictions of fatigue properties and designing against fatigue. These objectives cannot be realized without a physical and mechanical understanding of all relevant conditions. In Chapter 2 the book starts with basic concepts of what happens in the material of a structure under cyclic loads. It illustrates the large number of variables which can affect fatigue properties and it provides the essential background knowledge for subsequent chapters. Different subjects are presented in the following main parts: • Basic chapters on fatigue properties and predictions (Chapters 2–8) • Load spectra and fatigue under variable-amplitude loading (Chapters 9–11) • Fatigue tests and scatter (Chapters 12 and 13) • Special fatigue conditions (Chapters 14–17) • Fatigue of joints and structures (Chapters 18–20) • Fiber-metal laminates (Chapter 21) Each chapter presents a discussion of a speci?c subject.
