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Bridge Instrumentation And The Development Of Non Destructive And Destructive Techniques Used To Estimate Residual Tendon Stress In Prestressed Girders
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Book Synopsis Bridge Instrumentation and the Development of Non-destructive and Destructive Techniques Used to Estimate Residual Tendon Stress in Prestressed Girders by : Brian M. Kukay
Download or read book Bridge Instrumentation and the Development of Non-destructive and Destructive Techniques Used to Estimate Residual Tendon Stress in Prestressed Girders written by Brian M. Kukay and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This research embodied a three-prong approach for directly determining the residual prestress force of prestressed concrete bridge girders. For bridges that have yet to be constructed, outfitting girders with instrumentation is a highly effective means of determining residual prestress force in prestressed concrete bridge girders. This constitutes the first prong. Still, many bridges are constructed without such instrumentation. For these bridges, a destructive technique can be used to directly determine the residual prestress in a prestressed concrete bridge girder. This implies that the girder(s) being tested have already been taken out of service. This constitutes the second prong. For bridges that are anticipated to remain in service that are lacking embedded instrumentation, the development of a non-destructive technique used to estimate the remaining force in the tendons of prestressed bridge girders is extremely important. This constitutes the third prong used to directly determine residual prestress force. The flexural capacity was also determined from field tests and compared to analytical estimates. By design, the code estimates are meant to be conservative. Alternatively, the residual prestress force for in-service members can be determined directly through the non-destructive technique presented in this research. As such, bridge service capacities can be determined directly and do not need to be conservatively estimated.
Book Synopsis Toward Development of a Non-destructive Technique to Measure the Available Prestress in Prestressed Concrete Girders by :
Download or read book Toward Development of a Non-destructive Technique to Measure the Available Prestress in Prestressed Concrete Girders written by and published by . This book was released on 1994 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Dissertation Abstracts International by :
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2008 with total page 850 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Experimental and Analytical Evaluation of Residual Capacity of Corrosion-Damaged Prestressed Concrete Bridge Girders by : Ali Alfailakawi
Download or read book Experimental and Analytical Evaluation of Residual Capacity of Corrosion-Damaged Prestressed Concrete Bridge Girders written by Ali Alfailakawi and published by . This book was released on 2020 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: The durability of infrastructure components, such as prestressed concrete bridge beams, can be significantly affected by long-term deterioration associated with corrosion. Corrosion is a major concern for bridges in Virginia, due to the frequent use of deicing salts during the winter, as well as the number of structures in marine environments. The residual capacity of corrosion damaged prestressed I-beams and box beams needs to be accurately estimated to determine if damaged bridges need to be posted, and to help with making informed decisions related to repair, rehabilitation and replacement of damaged bridges. This report presents the results of testing of six corrosion-damaged prestressed beams removed from existing bridges during their demolition. Three beams were Type II AASHTO I-beams extracted from the Lesner Bridge in Virginia Beach, and three were 48 in wide by 27 in deep box beams extracted from the Aden Road Bridge near Quantico, Virginia. Prior to testing, the beams were visually inspected and two types of non-destructive evaluations were performed to identify corrosion activity: resistivity measurements and half-cell potential measurements. The beams were then tested in the lab to determine their flexural strength. Following testing, samples of strand were removed and tested to determine their tensile properties. Cores were taken from the Aden Road beams and from both the beams and decks of the Lesner Bridge beams to determine compressive strength. Powdered concrete samples were removed to perform chloride concentration tests. The tested strengths of the beams were compared to calculated strengths using two methods for damage estimation and two different calculation approaches. The methods for damage estimation relied exclusively on visual inspections; one was the set of methods recommended by Naito et al. (2010), while the second was a modified method developed in this study from the current tests. The two calculation approaches were a strain compatibility method and the AASHTO LRFD method. Overall, the results yielded reasonable estimates of residual strength, except for one of the box beams that was discovered to have considerable water within the hollow cells. The final recommendations are that bridge inspectors develop detailed damage maps of corrosion-damaged beams, and that load raters use the Naito et al. method to get a conservative estimate of damage for both box beams and I-beams. Either method for calculating strength is valid, however the AASHTO LRFD method is simpler.
Book Synopsis Prestress Losses in Pretensioned High-strength Concrete Bridge Girders by : Maher K. Tadros
Download or read book Prestress Losses in Pretensioned High-strength Concrete Bridge Girders written by Maher K. Tadros and published by Transportation Research Board. This book was released on 2003 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The HCM includes three printed volumes (Volumes 1-3) that can be purchased from the Transportation Research Board in print and electronic formats. Volume 4 is a free online resource that supports the rest of the manual. It includes: Supplemental chapters 25-38, providing additional details of the methodologies described in the Volume 1-3 chapters, example problems, and other resources; A technical reference library providing access to a significant portion of the research supporting HCM methods; Two applications guides demonstrating how the HCM can be applied to planning-level analysis and a variety of traffic operations applications; Interpretations, updates, and errata for the HCM (as they are developed);A discussion forum allowing HCM users to ask questions and collaborate on HCM-related matters; and Notifications of chapter updates, active discussions, and more via an optional e-mail notification feature."--Publisher.
Book Synopsis Instrumentation and Monitoring of High Performance Concrete Prestressed Bridge Girders by : Vellore S. Gopalaratnam
Download or read book Instrumentation and Monitoring of High Performance Concrete Prestressed Bridge Girders written by Vellore S. Gopalaratnam and published by . This book was released on 2001 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Acoustic Emission Sensing for Crack Monitoring in Prefabricated and Prestressed Reinforced Concrete Bridge Girders by : Robert Lee Worley (II)
Download or read book Acoustic Emission Sensing for Crack Monitoring in Prefabricated and Prestressed Reinforced Concrete Bridge Girders written by Robert Lee Worley (II) and published by . This book was released on 2019 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: Prefabricated and pre-stressed reinforced concrete beams and girders are integral components of many highway structures, including those built by rapid construction techniques. Concerns exist regarding the development of cracks during curing, form removal, detensioning, transport, installation, and operation. Non-destructive, Acoustic Emission (AE) sensing techniques have the potential for detecting and locating cracking in prefabricated, pre-stressed concrete girders used as Prefabricated Bridge Elements and Systems (PBES) used in rapid construction practices as part of a Quality Assurance/Quality Control (QA/QC) program. AE sensing records transient elastic waves produced by the release of stored elastic energy resulting in plastic deformations (i.e., crack nucleation and growth) with an array of point sensors. The AE instrument system is relatively portable which can allow for it to be an option for both off-site fabrication QA/QC as well as on-site field QA/QC. This thesis presents a multi-stage research initiative on acoustic emission monitoring of prefabricated and pre-stressed reinforced concrete beams used in highway bridge construction during detensioning, craned removal from formwork and transport to bridge sites, along with supporting laboratory tests and numerical analysis. The specific objectives of this research were to: 1. Identify suitable instruments to monitor pre-stressed and/or post-tensioned concrete girders for cracking activity; 2. Design and develop a reusable instrumentation package; 3. Measure performance and condition of concrete girders during fabrication and transport; and 4. Identify test protocols and possible accept/fix/reject criteria for structural elements based on information from monitoring system. Presented are results from laboratory, full-scale girder fabrication, and transport monitoring, along with overall conclusions and recommendations for future research.
Book Synopsis Non-destructive Evaluation Method for Determination of Internal Grout Conditions Inside Bridge Post-tensioning Ducts Using Rolling Stress Waves for Continuous Scanning by : Tinkey Yajai
Download or read book Non-destructive Evaluation Method for Determination of Internal Grout Conditions Inside Bridge Post-tensioning Ducts Using Rolling Stress Waves for Continuous Scanning written by Tinkey Yajai and published by . This book was released on 2006 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Innovations Deserving Exploratory Analysis project developed a nondestructive method based on impact-echo and ultrasonic reflection techniques with continuous scanning features for determining the grout condition inside post-tensioned bridge ducts. Initial efforts were focused on evaluating and establishing the accuracy/reliability of the impact echo scanning test. The impact echo scanner hardware was modified by incorporating a rolling transducer into the prototype to overcome the problem of variable thickness. The scanner software was also improved to provide three-dimensional display of impact echo results. Data on a mock-up slab fabricated with defects of different types and sizes and collected using the modified instrument were analyzed. Visualization from three-dimensional surface plots helped interpret the data. The presence of a tendon duct and grouting discontinuities appeared to cause an increase in the apparent slab thickness. Two U-shaped precast bridge girders with four ducts on each wall were procured from the Colorado Department of Transportation for full-scale tests. Impact echo tests using a rolling scanner at different times after the grouting process were performed on the walls of the girders.
Book Synopsis Method to Evaluate Remaining Prestress in Damaged Prestressed Bridge Girders by : Scott Adam Civjan
Download or read book Method to Evaluate Remaining Prestress in Damaged Prestressed Bridge Girders written by Scott Adam Civjan and published by . This book was released on 1995 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Nondestructive Testing of Prestressed Bridge Girders with Distributed Damage by : B. V. Tinkey
Download or read book Nondestructive Testing of Prestressed Bridge Girders with Distributed Damage written by B. V. Tinkey and published by . This book was released on 2002 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis The Use of Nondestructive Testing Methods for the Condition Assessment of Concrete Bridge Girders by : Richard Cornelius Unruh
Download or read book The Use of Nondestructive Testing Methods for the Condition Assessment of Concrete Bridge Girders written by Richard Cornelius Unruh and published by . This book was released on 2004 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are over 594,000 publicly controlled bridges in the United States. Concrete and pre-stressed concrete bridges account for nearly 50% of the bridges in the US inventory. This proportion is increasing each year, as new bridges tend to be constructed of concrete. This trend makes it vital for engineers to be able to accurately assess the condition of concrete for maintenance and repair decisions. The use of nondestructive testing methods can help reduce the backlog of deficient bridges in two ways. First, these techniques will allow inspectors to get a more accurate view of the condition of a bridge. The second way by which NDT can help is by allowing inspectors to locate damage earlier. This thesis is an attempt to capture the most current ideas for a very specific application of NDT: determining the condition of reinforced concrete bridges overall and bridge girders, in particular. To this end, attention is given to why NDT is needed and what aspects of concrete condition can be addressed with NDT. Some NDT methodologies that are, or may soon be, promising for concrete applications are discussed. Case studies are presented to demonstrate how NDT can be applied to concrete bridge girders and proposals are made for future areas of study and development.
Book Synopsis Techniques for Measuring Existing Long-term Stresses in Prestressed Concrete Bridges by :
Download or read book Techniques for Measuring Existing Long-term Stresses in Prestressed Concrete Bridges written by and published by . This book was released on 1990 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Various stress measurement techniques were evaluated in this study. The evaluation included a state-of-the-art review of existing techniques and analytical studies of these techniques. Based on analytical results, the flat-jack direct stress measurement technique was evaluated in laboratory and field tests. Based on these tests, a manual of instruction was written to describe the equipment and procedures required to obtain reliable direct stress measurement. This is the Executive Summary which summarizes the findings of this research project.
Book Synopsis Structural Health Monitoring for Suspension Bridges by : Yang Deng
Download or read book Structural Health Monitoring for Suspension Bridges written by Yang Deng and published by Springer. This book was released on 2018-12-19 with total page 243 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents extensive information on structural health monitoring for suspension bridges. During the past two decades, there have been significant advances in the sensing technologies employed in long-span bridge health monitoring. However, interpretation of the massive monitoring data is still lagging behind. This book establishes a series of measurement interpretation frameworks that focus on bridge site environmental conditions, and global and local responses of suspension bridges. Using the proposed frameworks, it subsequently offers new insights into the structural behaviors of long-span suspension bridges. As a valuable resource for researchers, scientists and engineers in the field of bridge structural health monitoring, it provides essential information, methods, and practical algorithms that can facilitate in-service bridge performance assessments.
Book Synopsis Material Properties of a Twenty-year-old Prestressed Bridge Girder Obtained by Nondestructive Testing by : Florie Bustamante Coggins
Download or read book Material Properties of a Twenty-year-old Prestressed Bridge Girder Obtained by Nondestructive Testing written by Florie Bustamante Coggins and published by . This book was released on 1989 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Development of Acoustic Emissions Testing Procedures Applicable to Conventionally Reinforced Concrete Deck Girder Bridges Subjected to Diagonal Tension Cracking by : Steven C. Lovejoy
Download or read book Development of Acoustic Emissions Testing Procedures Applicable to Conventionally Reinforced Concrete Deck Girder Bridges Subjected to Diagonal Tension Cracking written by Steven C. Lovejoy and published by . This book was released on 2006 with total page 1068 pages. Available in PDF, EPUB and Kindle. Book excerpt: A need exists to develop a non-destructive testing technique that can identify the formation and propagation of diagonal tension cracks in conventionally steel reinforced concrete deck girder (RCDG) highway bridges in the State of Oregon. Such a technique could be included into a structural health monitoring (SHM) system installed on specific bridges to automatically monitor the current state of structural damage in primary load supporting elements and provide notification of recent damage to bridge engineers in nearly real time. This research investigates the practical application of AE used to supplement a conventional SHM on vintage RCDG bridges. Background work presented in the Appendices investigates stress wave propagation in non-reinforced and steel reinforced concrete media. Based on the characterization of stress wave speeds, amplitude attenuation, frequency content and wave forms found in concrete media, testing methods are developed and applied to 31 full sized RCDG test specimens that include variations in loading, load capacity and structural detailing. Several different AE test procedures are used to characterize the damage states of the test beams as they are progressively loaded to failure. Four previously developed AE parameters that characterize both damage progression and damage state are applied which include the Felicity and Calm Ratios, Severity and the Historic Index. Both Felicity and Calm Ratios were found to respond to the damage state of the test beam as determined from more conventional assessment methods such as crack width and load. For the practical in-service loading ranges of 20 to 80% of ultimate capacity both the Felicity and Calm Ratios were found to respond in a nearly linear manner with increasing damage. Three categories of damage state are defined which are based on the ODOT crack comparator tool which is used for in-service maintenance inspections of these bridges. Felicity and Calm Ratio values are related to these damage states for the specific type of bridge girders being tested and can be used to estimate in-service damage states. The Severity and Historic Index responses were found to be an effective means of identifying the formation and extension of diagonal tension cracks as they developed. Threshold levels for these two parameters are identified for specific AE sensor types when applied to this class of bridge girder. A preliminary set of AE testing and analysis procedures were developed that were applied to three in-service bridges. These bridge tests used both controlled and ambient loading protocols. The structural response to each load case was quantified by using both crack width motion and reinforcing steel strain range. These structural parameters were correlated with the AE data. The Calm Ratio was found to be of practical importance and that the values recorded were in reasonably good agreement with the laboratory data once the imposed loads and current crack widths were considered. The Severity and Historic Index were also found to be of practical importance to bridge testing and structural health monitoring as they were found to be very sensitive to increasing damage, yet exhibit good stability provided enough AE activity was present. A recommend set of guidelines and practices for applying AE to vintage RCDG bridges is developed and presented.
Book Synopsis Evaluation and Repair Procedures for Precast/prestressed Concrete Girders with Longitudinal Cracking in the Web by : Maher K. Tadros
Download or read book Evaluation and Repair Procedures for Precast/prestressed Concrete Girders with Longitudinal Cracking in the Web written by Maher K. Tadros and published by . This book was released on 2010 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report establishes a user's manual for the acceptance, repair, or rejection of precast/prestressed concrete girders with longitudinal web cracking. The report also proposes revisions to the AASHTO LRFD Bridge Design Specifications and provides recommendations to develop improved crack control reinforcement details for use in new girders. The material in this report will be of immediate interest to bridge engineers.
Book Synopsis Nondestructive Evaluation of Bridges and Highways III by : Steve B. Chase
Download or read book Nondestructive Evaluation of Bridges and Highways III written by Steve B. Chase and published by SPIE-International Society for Optical Engineering. This book was released on 1999 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:
