Download or read book Load Rating and Evaluation of Two Prestressed Concrete Box Girder Bridges with No Plans Using Non destructive Load Testing written by Dagmawie Degif Shikurye and published by . This book was released on 2014 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridges with no plans are currently an issue in various states including New Mexico as many exist throughout the United States. Since these bridges have no existing plans and documentation, conventional load rating procedures can't be employed. Therefore in this research project, a four step procedure was developed for the load rating of prestressed concrete box girder bridges without plans. First, the total number and eccentricity of the prestressing strands in the bridge beams are estimated using Magnel diagrams. Second, material properties are obtained from the AASHTO Manual for Bridge Evaluation, AASHTO Standard Specifications, and/or the New Mexico provisions. Second, a Hilti PS 250 Ferroscan is used to detect the steel in the prestressed concrete beams and check the strand estimate and also determine the layout of the shear reinforcement. In addition, the concrete strength is estimated using a Windsor probe. Third, a diagnostic load test is performed to evaluate the in-service behavior and to measure the beam strains under a truck load approximately 60% of the target proof load determined based on the prestressing strand estimate and allowable tensile stress at service. Strain measurements are taken at critical locations to monitor the bridge response during the test. The objectives of this test are to determine the critical transverse truck path (i.e., ones producing the largest measured strains) and compare the measurements with analytical predictions. Fourth, a proof load test is conducted following the critical truck paths and under increasing truck loading until the allowable tensile stress or the target proof load is reached (whichever comes first). Results from the proof test are used to determine rating factors for legal loads. The AASHTOWare BrR software program is also used for purpose of comparison with the rating factors from the proof test. Two prestressed concrete box girder bridges in New Mexico located in Doña Ana County (Bridge 7722) and Bernalillo County (Bridge 8825) were evaluated in this study. For Bridge 7722, the BrR design ratings under HS-20 truck loading were computed as 1.073 and 1.791 at the inventory and operating level, respectively. Inventory and operating factors of 0.882 and 1.403, respectively, were obtained for Bridge 8825. These results, in particular the operating ratings greater than 1.0, provided the needed confidence to proceed with the load tests. Based on the results of the proof tests, rating factors were computed for New Mexico and AASHTO legal loads according to the AASHTO Manual for Bridge Evaluations. The lowest rating factors were 1.09 and 1.17 for Bridge 7722 and Bridge 8825, respectively, which showed that the two bridges did not need to be load posted for legal loads.
Download or read book Evaluation and Load Rating of a Prestressed Concrete Double T beam Bridge and a Prestressed Concrete I girder Bridge Without Design Plans written by Carlos Victor Aguilar and published by . This book was released on 2015 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridges without design plans are an existing problem as conventional load rating techniques cannot be utilized when there is no design documentation available to indicate the amount and location of reinforcement. A project was conducted for the New Mexico Department of Transportation to evaluate bridges without plans with various superstructures (T-beam, I-girder, and box girder) using advanced structural analysis and non-destructive experimental methods, with the goal of developing specific load rating procedures. This study presents two of the bridges that were evaluated. Bridge 7701 is a prestressed concrete double T-beam bridge located in Doña Ana County, NM. Upon inspection, it was discovered that many of the shear keys connecting the bridge beams were damaged or missing. Prestressing strand estimates were made based on Magnel diagrams and verified with a Hilti Ferroscan system. Diagnostic load testing was performed to determine the impact of the damaged shear keys on the live load distribution of the bridge. The results were then used to plan and conduct a proof test. Final legal load rating factors were subsequently determined from the proof test, and compared with the results from an AASHTOWare BrR load rating analysis. The final load rating factors show that Bridge 7701 needs to be load posted. Bridge 8588 is a prestressed concrete I-girder bridge located in Eddy County, NM. Similar to Bridge 7701, Magnel diagrams were used to develop prestressing strand estimates (based on composite and non-composite behavior) and attempts were made to verify layouts using a Hilti Ferroscan system. Since no significant girder damage was found during the inspection, no diagnostic load test was performed. Only a proof test was conducted and the results were used to compute load rating factors. The factors from the proof test were subsequently checked with the AASHTOWare BrR results, and final legal load rating factors were determined showing that Bridge 8588 does not need to be load posted. Using the evaluation procedures developed for Bridges 7701 and 8588, as well as three other bridges that were separately evaluated in this project, a final implementation plan for load rating prestressed concrete bridges without plans is presented.
Download or read book Evaluation of Planless Prestressed Concrete Double T beam Bridges Without Experimental Load Rating Tests written by Byungkwan Kim and published by . This book was released on 2016 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: Analytical load rating methods were conducted to evaluate prestressed concrete double T-beam bridges without design plans. Due to having no design plans, concrete and prestressing properties were assumed to estimate the number and location of the prestressing strands. A range of required prestressing area was estimated based on Magnel Diagram. The location of the strands (i.e., eccentricity) was verified by a Hilti Ferroscan system to reduce the range of required prestressing area. AASHTOWare BrR load rating analysis was generated based on the estimated prestressing area with multiple prestressing diameters. Because the AASHTOWare BrR load rating results were analyzed based on several assumptions, a "confidence level" for the assumptions was computed to reflect the accuracy and reliability of each assumption. The confidence level of the assumptions was considered for the distribution factor, concrete properties, prestress losses, prestessing forces, prestressing diameter, number of prestressing strands, eccentricity, and bridge condition and performance with an overall reduction factor of 80%. The AASHTOWare BrR load rating results were adjusted according to an average of the confidence level of the assumptions as a reduction factor. Six prestressed double T-beam bridges located in Doña Ana County, New Mexico (Bridge 8761, 7705, 7712, 7710, 7723, and 7713) were evaluated using the developed procedures. Bridge 8761 has original design plans and calculations, and proof test results unlike the other bridges. However, Bridge 8761 was treated as a bridge without plans to validate the estimation procedures and results. From the results of Bridge 8761, the adjusted load rating and proof testing results had a lower load rating factor compared to the original design plan results, indicating the procedure provides conservative ratings. Furthermore, the lowest adjusted load rating results had 6% lower rating factors than the proof test results, which was more conservative. From the adjusted load rating results, Bridge 7705, 7712, 7723, and 7713 do not need to have experimental load rating test performed. However, it is recommended that experimental load rating tests be conducted for Bridge 7710 to assure proper safety. This analytical load rating procedure provided an initial load rating estimation to avoid performing experimental load rating tests for saving cost and time.
Download or read book Load Distribution and Ultimate Strength of an Adjacent Precast Prestressed Concrete Box Girder Bridge written by Tyler W. Stillings and published by . This book was released on 2012 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: A decommissioned, adjacent precast, prestressed concrete box girder bridge constructed in 1967 was load tested to destruction in August and September of 2010. The bridge, which crossed Paint Creek approximately nine miles (14.5 km) northeast of Washington Court House, Ohio, consisted of three simple spans, each 47 ft. 10 in. (14.6 m) long. Each span was comprised of nine, 21 in. (533.4 mm) deep by 36 in. (914.4 mm) wide prestressed concrete box beams for a total width of up to 27 ft. 4 in. (8.3 m) with a 15° left-forward skew. Prior to testing, the bridge appeared to be in good condition, with the vast majority of deterioration limited to concrete spalling from the exterior webs of the fascia girders. Of the three spans tested, this thesis details testing and analysis of the first two. In addition to environmental deterioration, the first span was damaged by researchers, whereas no additional damage was done to the second. Loads were applied via three, 350 kip (1557 kN) hydraulic cylinders supported by steel load frames. Test data collected from pressure transducers, wire potentiometers, and strain gauges were compared to predictions from a reinforced concrete modeling program. Beam capacity and bridge distribution factors were compared to values calculated from the AASHTO LRFD Bridge Design Specifications. Data analysis shows that the response of the bridge was predicted well by the analysis program for both low-level destructive and ultimate destructive loads. It was determined that bridge capacity could be found by summing the capacity of each individual beam, as long as the calculated capacity is reduced for the effects of damage. The bridge maintained its ability to transmit load between girders even after cracking of shear keys, indicating that steel tie rods play a major role in transmitting load from one beam to the next.
Download or read book Load Testing of Bridges written by Eva Lantsoght and published by CRC Press. This book was released on 2019-06-19 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: Load Testing of Bridges, featuring contributions from almost fifty authors from around the world across two interrelated volumes, deals with the practical aspects, the scientific developments, and the international views on the topic of load testing of bridges. Volume 12, Load Testing of Bridges: Current practice and Diagnostic Load Testing, starts with a background to bridge load testing, including the historical perspectives and evolutions, and the current codes and guidelines that are governing in countries around the world. The second part of the book deals with preparation, execution, and post-processing of load tests on bridges. The third part focuses on diagnostic load testing of bridges. This work will be of interest to researchers and academics in the field of civil/structural engineering, practicing engineers and road authorities worldwide.
Download or read book Development of a Load Test for the Evaluation and Rating of Short span Reinforced Concrete Slab Bridges written by Amy Eitel and published by . This book was released on 2002 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: There exists in the state of Ohio a large inventory of short span reinforced concrete bridges, particularly on rural secondary highways, whose actual structural reliability cannot be accurately ascertained. Quite often little or no documentation exists to assist the responsible local jurisdictions in assessing the ability of these bridges to safely carry modern truck loading.
Download or read book Guidelines for the Supplementary Load Testing of Bridges written by Institution of Civil Engineers (Great Britain). National Steering Committee for the Load Testing of Bridges and published by Thomas Telford. This book was released on 1998 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridge authorities in the UK are currently facing a large programme of bridge assessment and strengthening. This has been caused, in part, by the necessity of ensuring that the European Union deadline for allowing 40-tonne lorries on to UK roads can be met. Many bridges have failed theoretical assessments and some bridge owners, frustrated by the fact that many failed structures are apparently in good condition and showing no signs of distress, have resorted to load testing their bridges to try to provide additional information. A National Steering Committee for the Load Testing of Bridges was set up to examine the role of bridge load testing as a tool for assisting the assessment process. The National Steering Committee consists of representatives from all major bridge owners including the Highways Agency, the County Surveyors Society, the London Bridges Engineering Group, Railtrack and the British Waterways Board. It also includes representatives from consulting engineers and universities and has the support of the Institution of Civil Engineers. The overall objective of the National Steering Committee was to produce authoritative guidance on load-testing techniques; which could be used by the practising engineer to determine capacities of existing bridges/structures that are safe, prudent and minimize levels of restriction to the transport infrastructure. In June 1995 the committee appointed Rendel Palmer & Tritton in association with Peter Lindsell & Associates and supported by Professors Bakht, Clark and Harding as consultants to carry out a preliminary study of all the available information on bridge load testing. They were to recommend a detailed methodology which would form the basis of a brief to consultants appointed to produce authoritative guidelines for the load testing of bridges. Their report concluded that there is a place for load testing in the evaluation of bridges and other structures and that load testing is a valid tool for bridge managers. They also concluded that there was enough information and experience available to permit safe and effective guidelines to be written. As a result of the preliminary study the National Steering Committee decided to divide the second stage work and restrict the scope of this document to guidelines for supplementary load testing. Work on proof and proving load testing is being carried out by others under the auspices of the Highways Agency. The guidelines contained in this document were not drafted in a prescriptive form, but seek to provide advice on the appropriate use of supplementary load testing as an aid to assessment by calculation. The guidelines have been written to enable engineers to determine: when it is appropriate to consider the use of supplementary load testing; the level of risk, both public safety and economic, associated with load testing; how to plan and carry out a load test including the level of expertise necessary, the appropriate loading methods and the type and quantity of instrumentation required. In addition, the document is intended to be a source of information on load testing, measuring equipment and specialist techniques that engineers can use for reference.
Download or read book Performance Evaluation of Existing Steel and Concrete Girder Bridges Through Non destructive Live load Testing written by Andrew E. Jeffrey and published by . This book was released on 2008 with total page 559 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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:
Download or read book Diagnostic and Proof Load Tests on Bridges written by Fikret Necati Catbas and published by Frontiers Media SA. This book was released on 2020-12-11 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: This eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contact.
Download or read book Development of Design Specifications and Commentary for Horizontally Curved Concrete Box girder Bridges written by Nutt, Redfield, and Valentine and published by Transportation Research Board. This book was released on 2008 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report provides specifications, commentary, and examples for the design of horizontally curved concrete box-girder highway bridges. The report details the development of the design procedures. Recommended Load and Resistance Factor Design (LRFD) specifications and design examples illustrating the application of the design methods and specifications are included in appendixes (available on the TRB website at http://trb.org/news/blurb_detail.asp?id=9596).
Download or read book Extending Span Ranges of Precast Prestressed Concrete Girders written by Reid Wilson Castrodale and published by Transportation Research Board. This book was released on 2004 with total page 603 pages. Available in PDF, EPUB and Kindle. Book excerpt: At head of title: National Cooperative Highway Research Program.
Download or read book Live load Distribution Factors and Shear Evaluation for a Prestressed Concrete Spread Box girder Bridge written by Jesse G. Tercero and published by . This book was released on 2009 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Testing and Analysis of a Continuous Prestressed Concrete Box Girder Bridge written by M. J. N. Priestley and published by . This book was released on 1977 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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.
Download or read book Load testing of prestressed concrete girder bridges in Texas written by Patrick Joseph Wagener and published by . This book was released on 2002 with total page 522 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monitoring and Load Distribution Study for the Land Bridge written by Alireza Ghorbanpoor and published by . This book was released on 2010 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt:
