Download or read book Development of Induced Magnetic Field Procedure for Nondestructive Evaluation of Deteriorated Prestressing Strand written by Michael D. Titus and published by . This book was released on 2011 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: The induced magnetic field (IMF) procedure for nondestructive evaluation of deteriorated prestressing strand predicts the sound cross-sectional area of strand in embedded concrete. The system utilizes an electromagnet that magnetizes the strand, and an array of hall sensors that measures Gauss readings that indicate the strength of the magnetic field of the strand. This technology allows bridge inspectors to go further than visual inspection when determining the condition of prestressed concrete beams. This thesis discusses the development of the IMF testing system, including both laboratory testing and a field test. During the course of this research, the magnetic flux leakage (MFL) testing procedure was also researched and utilized. The first documented field test of its kind was performed using magnetic inspection on a prestressed box beam bridge. The IMF system accurately predicted corrosion in a laboratory setting, and predicted corrosion during the field test, albeit with limited accuracy. The MFL method predicted corrosion more accurately in the field test.

Download or read book Magnetic Sensor for Nondestructive Evaluation of Deteriorated Prestressing Strand written by Douglas K. Nims and published by . This book was released on 2011 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report gives an account of the execution and achievements in Phase II of the project completed through August 2011. The main objective of this project is to advance the practical development of a nondestructive testing and evaluation method using the magnetic field technique to estimate corrosion in prestressing strands. The importance of developing such a method has been well established. Phase I and the literature review established the proof of concept for a magnetic inspection method. The magnetic technique of induced magnet field (IMF) was developed.

Download or read book Nondestructive Evaluation of Deteriorated Prestressing Strands Using Magnetic Field Induction written by Bertrand Fernandes and published by . This book was released on 2010 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: A design, fabrication and proof of concept testing of a sensor system, based on magnetic field detection, to estimate the remaining cross sectional area in corroded prestressing strands was undertaken. Corrosion detection in prestressed concrete has been a challenging task since the most common way of doing it is by visual inspection. An electromagnet with Hall sensors was designed to estimate the cross sectional area of steel rods and prestressing strands of different diameters in a laboratory. The electromagnet induces a magnetic field in the steel bar/strand sample when magnetized from one side and at a distance from the magnet pole face. The induced magnetic field was found reliably proportional to the cross section area of the steel bar when magnetized near magnetic saturation, for a combination of various diameters, and distances of up to two inches from the pole face. The laboratory experiments were carried out using steel bars and prestressing strands with and without concrete cover. Magnetic field measurements of the corroded strand specimens are compared to those with sound ones. The effective remaining sound cross section area of the corroded specimen was then estimated, using the measurements of healthy specimens as a reference. The effective cross section area was correlated to different corrosion degrees. The effect of concrete on the magnetization process was analyzed. The results confirm that accurate measurement of the cross sectional area in a laboratory setting is possible with the proposed magnetic technique. The successful implementation of this sensor in nondestructive evaluation of bridges will be of great help for bridge condition assessment.

Download or read book Magnetic Sensor for Nondestructive Evaluation of Deteriorated Prestressing Strand written by James David Wade and published by . This book was released on 2010 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this thesis was to develop a non-destructive in-situ magnetic technique to investigate the remaining cross-sectional area of prestressing strands. Corrosion is the predominate failure-mechanism in box-beam bridges. The current method, visual inspection, is not sufficient as the strands may not be exposed to the investigator. An inaccurate estimate of the remaining area of strands can lead to an overestimated strength of the bridge. A new technique involving an electromagnet and magnetic theories was researched for this thesis. The experiments conducted have shown that it is possible to distinguish between different cross-sectional areas using an electromagnet and Hall sensors. Experiments with an air-gap were first used to simulate concrete cover and provide viability of the technique. These experiments showed that as the cross-sectional area increased so did the induced magnetic field. To further the research, concrete blocks were used in place of the air-gap to better simulate field conditions. Again, these experiments showed an increase in the induced magnetic field as the cross-sectional area was increased. Using the data from the air-gap and concrete block experiments, an approach to determine the cross-sectional area of a corroded strand under concrete cover was investigated.

Download or read book Development of a Magnetic Field Sensor System for Nondestructive Evaluation of Reinforcing Steel in Prestressed Concrete Bridge Members written by Bertrand Fernandes and published by . This book was released on 2012 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nondestructive evaluation of prestressed concrete mainly includes inspection of the condition of the prestressing strands for load rating. This thesis presents a magnetic inspection system to measure main magnetic flux (MMF) and magnetic leakage flux (MFL) signals, to evaluate the condition of prestressing stands. A proof-of-concept has been established using a prototype electromagnet-sensor, showing a direct relationship between the cross-sectional area of the strand and the magnitude of magnetic field induced in it. A field test of a box-beam bridge was conducted using both MMF and MFL detection techniques separately. This led to the realization of a comprehensive MMF-MFL electromagnet-sensor system for inspection of prestressed steel in concrete. A computer aided simulation model was created to model the magnetic field signals and aid in better understanding of the electromagnet-sensor. This model is also useful for generating expected magnetic field signals from magnetization of different strand size and configuration setups and thus, helps in making corrosion estimations. The MMF-MFL signal detection concept was evaluated using the existing electromagnet-sensor in a laboratory setup and on prestressed box-beams obtained from a demolished bridge. It was able to identify corrosion and defects such as breaks or fractures in prestressing strands. For this magnetic inspection system to become practical, certain modifications such as redesign of the magnetic field generated by the magnet to have higher resolution have been suggested. Other features such as accurate measurement of pole face to strand distance and weight reduction have been discussed. The overall outcome of this research has shown that magnetic field signals can be useful to detect hidden corrosion in prestressed box-beams.

Download or read book Magnetic Flux Leakage Device for Evaluation of Prestressed Concrete Box Bridges written by Steve B. Chase and published by . This book was released on 2020 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Handbook on Nondestructive Testing of Concrete written by V. M. Malhotra and published by CRC Press. This book was released on 2004 with total page 389 pages. Available in PDF, EPUB and Kindle. Book excerpt: Civil engineers will value this resource that examines the tools and techniques used to estimate the in-place strength on concrete, permeation properties that relate to potential durability, and the methods used to assess the internal condition of concrete and the corrosion activity of steel reinforcement.

Download or read book Materials Evaluation written by and published by . This book was released on 1994 with total page 838 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Prestressed Concrete Bridges written by Christian Menn and published by Birkhäuser. This book was released on 2012-12-06 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book was written to make the material presented in my book, Stahlbetonbrucken, accessible to a larger number of engineers throughout the world. A work in English, the logical choice for this task, had been contemplated as Stahlbetonbrucken was still in its earliest stages of preparation. The early success of Stahlbetonbrucken provided significant impetus for the writing of Prestressed Concrete Bridges, which began soon after the publication of its predecessor. The present work is more than a mere translation of Stahlbetonbrucken. Errors in Stahlbetonbrucken that were detected after publication have been corrected. New material on the relation between cracking in concrete and corrosion of reinforce ment, prestressing with unbonded tendons, skew-girder bridges, and cable-stayed bridges has been added. Most importantly, however, the presentation of the material has been extensively reworked to improve clarity and consistency. Prestressed Concrete Bridges can thus be regarded as a thoroughly new and improved edition of its predecessor.

Download or read book Emerging Technologies in Non Destructive Testing VI written by Danny Van Hemelrijck and published by CRC Press. This book was released on 2015-11-24 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt: Non-Destructive Testing (NDT) is of worldwide significance, and is strongly related to the detection of damage in engineering structures (buildings, bridges, aircrafts, ships, pressure vessels, etc.) using non-invasive techniques (ultrasound, X-rays, Radar, neutrons, thermography, vibrations, acoustic emission, etc.). Emerging Technologies in Non-D

Download or read book Non Destructive Evaluation of Corrosion and Corrosion assisted Cracking written by Raman Singh and published by John Wiley & Sons. This book was released on 2019-04-09 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive text to the non-destructive evaluation of degradation of materials due to environment that takes an interdisciplinary approach Non-Destructive Evaluation of Corrosion and Corrosion-assisted Cracking is an important resource that covers the critical interdisciplinary topic of non-destructive evaluation of degradation of materials due to environment. The authors—noted experts in the field—offer an overview of the wide-variety of approaches to non-destructive evaluation and various types of corrosion. The text is filled with instructive case studies from a range of industries including aerospace, energy, defense, and processing. The authors review the most common non-destructive evaluation techniques that are applied in both research and industry in order to evaluate the properties and more importantly degradation of materials components or systems without causing damage. Ultrasonic, radiographic, thermographic, electromagnetic, and optical are some of the methods explored in the book. This important text: Offers a groundbreaking interdisciplinary approach to of non-destructive evaluation of corrosion and corrosion-assisted cracking Discusses techniques for non-destructive evaluation and various types of corrosion Includes information on the application of a variety of techniques as well as specific case studies Contains information targeting industries such as aerospace, energy, processing Presents information from leading researchers and technologists in both non-destructive evaluation and corrosion Written for life assessment and maintenance personnel involved in quality control, failure analysis, and R&D, Non-Destructive Evaluation of Corrosion and Corrosion-assisted Cracking is an essential interdisciplinary guide to the topic.

Download or read book Non Destructive Evaluation of Reinforced Concrete Structures written by Christiane Maierhofer and published by Elsevier. This book was released on 2010-07-27 with total page 631 pages. Available in PDF, EPUB and Kindle. Book excerpt: Engineers have a range of sophisticated techniques at their disposal to evaluate the condition of reinforced concrete structures and non-destructive evaluation plays a key part in assessing and prioritising where money should be spent on repair or replacement of structurally deficient reinforced concrete structures. Non-destructive evaluation of reinforced concrete structures, Volume 2: Non-destructive testing methods reviews the latest non-destructive testing techniques for reinforced concrete structures and how they are used.Part one discusses planning and implementing non-destructive testing of reinforced concrete structures with chapters on non-destructive testing methods for building diagnosis, development of automated NDE systems, structural health monitoring systems and data fusion. Part two reviews individual non-destructive testing techniques including wireless monitoring, electromagnetic and acoustic-elastic waves, laser-induced breakdown spectroscopy, acoustic emission evaluation, magnetic flux leakage, electrical resistivity, capacimetry, measuring the corrosion rate (polarization resistance) and the corrosion potential of reinforced concrete structures, ground penetrating radar, radar tomography, active thermography, nuclear magnetic resonance imaging, stress wave propagation, impact-echo, surface and guided wave techniques and ultrasonics. Part three covers case studies including inspection of concrete retaining walls using ground penetrating radar, acoustic emission and impact echo techniques and using ground penetrating radar to assess an eight-span post-tensioned viaduct.With its distinguished editor and international team of contributors, Non-destructive evaluation of reinforced concrete structures, Volume 2: Non-destructive testing methods is a standard reference for civil and structural engineers as well as those concerned with making decisions regarding the safety of reinforced concrete structures. - Reviews the latest non-destructive testing (NDT) techniques and how they are used in practice - Explores the process of planning a non-destructive program features strategies for the application of NDT testing - A specific section outlines significant advances in individual NDT techniques and features wireless monitoring and electromagnetic and acoustic-elastic wave technology

Download or read book ACI 228 2R 13 Report on Nondestructive Test Methods for Concrete in Structures written by American Concrete Institute and published by . This book was released on 2013 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: "A review is presented of nondestructive test (NDT) methods for evaluating the condition of concrete and steel reinforcement in structures. Methods discussed include visual inspection, stress-wave, nuclear, measurement of fluid transport properties, magnetic and electrical, infrared thermography, and ground-penetrating radar. The principle of each method is discussed and the typical instrumentation described. Testing procedures are summarized and the data analysis methods explained. The advantages and limitations of the methods are highlighted. This report concludes with a discussion of planning a NDT program. General information is provided for those faced with the tast of evaluating the condition of a concrete structure and who are considering the applicability of NDT methods to aid in that evaluation."--p. 1.

Download or read book Engineering and Design written by Us Army Corps Of Engineers and published by Military Bookshop. This book was released on 1995-06 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: This manual provides guidance on evaluating the condition of the concrete in a structure, relating the condition of the concrete to the underlying cause or causes of that condition, selecting an appropriate repair material and method for any deficiency found, and using the selected materials and methods to repair or rehabilitate the structure. Guidance is also included on maintenance of concrete and on preparation of concrete investigation reports for repair and rehabilitation projects. Considerations for certain specialized types of rehabilitation projects are also given.

Download or read book Model Code for Service Life Design written by fib Fédération internationale du béton and published by fib Fédération internationale du béton. This book was released on 2006-01-01 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: fib Bulletin 34 addresses Service Life Design (SLD) for plain concrete, reinforced concrete and pre-stressed concrete structures, with a special focus on design provisions for managing the adverse effects of degradation. Its objective is to identify agreed durability related models and to prepare the framework for standardization of performance based design approaches. Four different options for SLD are given: - a full probabilistic approach, - a semi probabilistic approach (partial factor design), - deemed to satisfy rules, - avoidance of deterioration. The service life design approaches described in this document may be applied for the design of new structures, for updating the service life design if the structure exists and real material properties and/or the interaction of environment and structure can be measured (real concrete covers, carbonation depths), and for calculating residual service life. The bulletin is divided into five chapters: 1. General 2. Basis of design 3. Verification of Service Life Design 4. Execution and its quality management 5. Maintenance and condition control It also includes four informative annexes, which give background information and examples of procedures and deterioration models for the application in SLD. The format of Bulletin 34 follows the CEB-FIP tradition for Model Codes: the main provisions are given on the right-hand side of the page, and on the left-hand side, the comments. Note: An Italian translation of Bulletin 34 is also available; contact us for further details.

Download or read book Failure Distress and Repair of Concrete Structures written by Norb Delatte and published by Elsevier. This book was released on 2009-10-26 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding and recognising failure mechanisms in concrete is a fundamental pre-requisite to determining the type of repair, or whether a repair is feasible. This title provides a review of concrete deterioration and damage, as well as looking at the problem of defects in concrete. It also discusses condition assessment and repair techniques.Part one discusses failure mechanisms in concrete and covers topics such as causes and mechanisms of deterioration in reinforced concrete, types of damage in concrete structures, types and causes of cracking and condition assessment of concrete structures. Part two reviews the repair of concrete structures with coverage of themes such as standards and guidelines for repairing concrete structures, methods of crack repair, repair materials, bonded concrete overlays, repairing and retrofitting concrete structures with fiber-reinforced polymers, patching deteriorated concrete structures and durability of repaired concrete.With its distinguished editor and international team of contributors, Failure and repair of concrete structures is a standard reference for civil engineers, architects and anyone working in the construction sector, as well as those concerned with ensuring the safety of concrete structures. - Provides a review of concrete deterioration and damage - Discusses condition assessment and repair techniques, standards and guidelines

Download or read book Maintenance Safety Risk Management and Life Cycle Performance of Bridges written by Nigel Powers and published by CRC Press. This book was released on 2018-07-04 with total page 5447 pages. Available in PDF, EPUB and Kindle. Book excerpt: Maintenance, Safety, Risk, Management and Life-Cycle Performance of Bridges contains lectures and papers presented at the Ninth International Conference on Bridge Maintenance, Safety and Management (IABMAS 2018), held in Melbourne, Australia, 9-13 July 2018. This volume consists of a book of extended abstracts and a USB card containing the full papers of 393 contributions presented at IABMAS 2018, including the T.Y. Lin Lecture, 10 Keynote Lectures, and 382 technical papers from 40 countries. The contributions presented at IABMAS 2018 deal with the state of the art as well as emerging concepts and innovative applications related to the main aspects of bridge maintenance, safety, risk, management and life-cycle performance. Major topics include: new design methods, bridge codes, heavy vehicle and load models, bridge management systems, prediction of future traffic models, service life prediction, residual service life, sustainability and life-cycle assessments, maintenance strategies, bridge diagnostics, health monitoring, non-destructive testing, field testing, safety and serviceability, assessment and evaluation, damage identification, deterioration modelling, repair and retrofitting strategies, bridge reliability, fatigue and corrosion, extreme loads, advanced experimental simulations, and advanced computer simulations, among others. This volume provides both an up-to-date overview of the field of bridge engineering and significant contributions to the process of more rational decision-making on bridge maintenance, safety, risk, management and life-cycle performance of bridges for the purpose of enhancing the welfare of society. The Editors hope that these Proceedings will serve as a valuable reference to all concerned with bridge structure and infrastructure systems, including students, researchers and engineers from all areas of bridge engineering.