Download or read book Analysis of a Damaged and Repaired Pre stressed Concrete Bridge Girder by Vehicle Impact and Effectiveness of Repair Procedure written by Félix Domínguez Mayans and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis aims to study the structural consequences of the damages produced by vehicle impact in a pres-stressed concrete bridge girder and the repair procedure in a real case-study damaged after the bridge was opened to service. From the analysis of the situation of the beam and its damage state, a study of the repair actions carried out on this beam has been analyzed in order to determine the efficiency of the repair and if other alternatives are possible or more efficient. A state of the art and current practice review for repairing similar damages is carried out in this thesis. This literature review is focused on the repair methods and techniques studied in the United States of America, where this thesis was performed. Furthermore, all repair methods are classified depending on the type of girder damage (minor, moderate and severe). This damage classification aims to avoid inefficient and improper repair actions. The most complex techniques are usually used with severe damage. After all techniques are studied and classified a repair strategy is proposed. Based on the information, concepts and techniques analyzed in the literature review, a repair procedure for a pres-stressed concrete bridge girder is proposed. All necessary steps to have a proper repair are carried out. Then, once repair strategy is proposed, a real case is studied. Following the repair strategy proposed, all steps needed to repair a pre-stressed concrete bridge girder damaged by vehicle impact are carried out. Doing this way, the suitability of the strategy proposed. A deeper understanding of the method used in this case and the process followed in its implementation is detailed. After the procedure is studied, an analysis of data from load tests performed on the beam before and after repair were made is done. With the data obtained from load tests a study of the correlation of results are done in order to obtain conclusions after repair. Finally, a simulation of the case-study is carried out in order to identify the effects of the damage in the bridge deck, structural response and the efficiency of the repair. This simulation is done using SAP 2000 structural analysis software.

Download or read book Repair of Impact Damaged Prestressed Concrete Bridge Girders Using Carbon Fiber Reinforced Polymer CFRP Materials written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Over-height vehicles impacting prestressed concrete (PS) and reinforced concrete (RC) bridge girders is a frequent problem experienced by the majority of transportation departments all over the world. The most common practice used to restore a damaged bridge is to cut out the damaged girder and replace it with a new one. More recently, alternative methods have been examined to help decrease the costs of replacing damaged girders and minimizing closure time. The research reported in this thesis considered three scenarios to examine the effectiveness of using Carbon Fiber Reinforced Polymers (CFRP) to restore impact-damaged PS girders to their original capacity. The first scenario investigated the effectiveness of CFRP sheets to repair a 54 ft (16.4 m) long girder with one ruptured prestressing strand caused by an over-height vehicle impact. The second scenario investigated the effectiveness of CFRP sheets to repair two 54 ft (16.4 m) long girders with various numbers of prestressing strands ruptured artificially at midspan. The final scenario examined the effectiveness of CFRP sheets to repair a shear-critical specimen with four prestressing strands artificially ruptured near the support. The design of all CFRP repair systems was conducted using a cracked section analysis and/or guidelines for shear capacity of prestressed members. The predictions according to the two approaches compared well with the measure values. The designs were compared to current codes and a recently developed debonding model. All of the repaired girders were able to reach and surpass their respective undamaged capacities. All of the flexural tests failed due to crushing of concrete and exhibited ductility even higher than the predicted value for the undamaged specimens.

Download or read book Repair of Impact Damaged Prestressed Concrete Girders Using Carbon Fiber Reinforced Polymers written by John David Rhodes and published by . This book was released on 2000 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: Every year several prestressed concrete (P/C) girder bridges are damaged by overheight vehicles. Traditional P/C girder repair strategies include beam replacement, internal strand splices, external post-tensioning, and welded steel jackets. Unfortunately, these types of repairs are both labor intensive and vulnerable to future corrosion. One possible alternative to these traditional repair techniques is to repair/strengthen impact damaged P/C girders with carbon fiber reinforced polymers (CFRP). These types of materials have the advantage of large strength/weight ratios, excellent corrosion/fatigue properties, and are relatively simple to install. This report describes the experimental results from three full-sized P/C beams that were intentionally damaged to simulate vehicle impacts, repaired, and tested. Damage consisted of removing concrete from the bottom flange and severing a number of prestressing strands. The beams were strengthened/repaired by patching the bottom flange and installing multiple layers unidirectional CFRP to restore the original flexural capacity. CFRP fibers were also used in the transverse direction to help confine the patch material and to prevent premature debonding of the longitudinal sheets. Service level and ultimate load tests were conducted to determine the effectiveness of CFRP strengthening system. A theoretical analysis of the strengthened/repaired beams was also completed. In addition to the full-size beams, a number of smaller specimens were also used to address durability and environmental concerns related to the use CFRP on bridge structures.

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 Transportation Research Board. This book was released on 2010 with total page 76 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.

Download or read book Repair of Impact damaged Prestressed Concrete Bridge Girder Using Glass FRP Rebar written by Maria Angeles De La Flor Montero and published by . This book was released on 2015 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt: Overpass girders are risked by the impact of the traffic, over height vehicle, travelling under the structure, creating a hazard for the drivers over and under the bridge. When a bridge girder is damaged the repair solution adopted has to meet the following criteria: - Safety. The repaired structure has to provide a minimum level of service to guarantee the safety of the traffic during the life of the structure. - Repair time: The repair time has to be minimized to limit risks and inconveniences for the traffic. - Economy. The adopted solution has not only to fulfill the previous requirements, but also has to be the most economical. Nowadays a lot of construction projects have to confront this kind of issue. The Lyndon B. Johnson (LBJ) Express construction project had to solve this problem. The LBJ project is located on I-635 and I-35 in North Dallas, Texas. The bridge number 54 of the LBJ project was hit by a truck, causing severe damage on one of its girders. The incident caused loss of concrete and exposed several strands. The solution adopted for the engineers was install fiber glass rebar and fill with repair mortar. This study models the damaged girder before and after the repair to analyze its structural behavior. The data obtained by this model have been compared to the data obtained by the field test. The ABAQUS software has been used to model the girder. The objectives of this study are provide a better understanding of the structural behavior and propose adequate modeling techniques of beams repaired with GFRP rebar. The proposed techniques will help to establish adequate repair procedures and to anticipate the structural behavior of damaged girders prior to the repair process

Download or read book Repair Method for Prestressed Girder Bridges written by Kent A. Harries and published by . This book was released on 2009 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is common practice that aging and structurally damaged prestressed concrete bridge members are taken out of service and replaced. This, however, is not an efficient use of materials and resources since the member can often be repaired in situ. There are numerous repair techniques proposed by entrepreneurial and academic institutions which restore prestressed concrete girder flexural strength and save both material and economic resources. Of course, not all repair methods are applicable in every situation and thus each must be assessed based on girder geometry and the objectives of the repair scenario. This document focuses on the practical application of prestressed concrete bridge girder repair methods. In this document, repair methods are presented for three prototype prestressed concrete highway bridge girder shapes: adjacent boxes (AB), spread boxes (SB), and AASHTO-type I-girders (IB), having four different damage levels. A total of 22 prototype repair designs are presented. Although not applicable to all structure types or all damage levels, the repair techniques covered include the use of carbon fiber reinforced polymer (CFRP) strips, CFRP fabric, near-surface mounted (NSM) CFRP, prestressed CFRP, post-tensioned CFRP, strand splicing and external steel post-tensioning. It is the authors' contention that each potential structural repair scenario should be assessed independently to determine which repair approach is best suited to the unique conditions of a specific project. Therefore, no broad classifications have been presented directly linking damage level (or a range of damage) to specific repair types. Nonetheless, it is concluded that when 25% of the strands in a girder no longer contribute to its capacity, girder replacement is a more appropriate solution. Guidance with respect to inspection and assessment of damage to prestressed concrete highway bridge girders and the selection of a repair method is presented. These methods are described through 22 detailed design examples. Based on these examples, review of existing projects and other available data, a detailed review of selection and performance criteria for prestressed concrete repair methods is provided. Best practices based on the study objectives are presented.

Download or read book Field laboratory Testing of Damaged Prestressed Concrete Girder Bridges written by and published by . This book was released on 1999 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to frequent accidental damage to prestressed concrete (P/C) bridges caused by impact from overheight vehicles, a project was initiated to evaluate the strength and load distribution characteristics of damaged P/C bridges. A comprehensive literature review was conducted. It was concluded that only a few references pertain to the assessment and repair of damaged P/C beams. No reference was found that involves testing of a damaged bridge(s) as well as the damaged beams following their removal. Structural testing of 2 damaged bridges was conducted in the field.

Download or read book CFRP Repair of Impact Damaged Bridge Girders Volume 1 Strcutural Evaluation of Impact Damaged Prestressed Concrete 1 Girders Repaired with FRP Materials written by Perry Green and published by CreateSpace. This book was released on 2012-12-24 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a research project that was recently completed to assist the Florida Department of Transportation in establishing a list of acceptable methods for the repair of impact damaged pre-stressed concrete bridge girders using fiber reinforced polymer materials.

Download or read book Heat straightening Repair of Damaged Steel Bridge Girders written by Robert J. Connor and published by Transportation Research Board. This book was released on 2008 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: TRB¿s National Cooperative Highway Research Program (NCHRP) Report 604: Heat-Straightening Repair of Damaged Steel Bridge Girders: Fatigue and Fracture Performance explores limits, based on fatigue and fracture performance, on the number of damage and repair cycles to which damaged steel bridge girders may be subjected using the heat-straightening procedure.

Download or read book Repair of Prestressed Concrete Girder Ends and Girder Collision Repair written by Chris P. Pantelides and published by . This book was released on 2010 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fiber reinforced polymer composites are an increasingly popular material that can be used for bridge girder retrofit/repair. The purpose of this research, therefore, is to develop methods and design guidelines for repair and retrofit of bridge girders suffering (1) shear strength deficiencies related to end cracking and (2) flexural strength deficiencies related to vehicular collision. Scaled test specimens were fabricated and subjected to cyclic loading in order to instigate damage similar to that caused by end cracking and vehicular collision. Subsequently, the damaged specimens were repaired with external post-tensioned carbon fiber rods and re-tested to failure. This report presents the data from the tests and design guidelines for the use of external post-tensioned carbon fiber rods for repair applications.

Download or read book Report written by and published by . This book was released on 1980 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Intermediate Diaphragms to Prestressed Concrete Bridge Girders in Over height Truck Impacts written by Pizhong Qiao and published by . This book was released on 2008 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation and repair of impact damaged prestressed concrete bridge girders written by Robert Steven Zobel and published by . This book was released on 1996 with total page 191 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Flexural Behavior of Laterally Damaged Full scale Bridge Girders Through the Use of Carbon Fiber Reinforced Polymers cfrp written by Nicholas James Alteri and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT The repair and strengthening of concrete bridge members with CFRP has become increasingly popular over recent years. However, significant research is still needed in order to develop more robust guidelines and specifications. The research project aims to assist with improving design prosedures for damaged concrete members with the use of CFRP. This document summarizes the analysis and testing of full-scale 40' foot long prestressed concrete (PSC) bridge girders exposed to simulated impact damage and repaired with carbon fiber reinforced polymers (CFRP) materials. A total of five AASHTO type II bridge girders fabricated in the 1960's were taken from an existing bridge, and tested at the Florida Department of Transportation FDOT structures lab in Tallahassee, Florida. The test specimens were tested under static loading to failure under 4-point bending. Different CFRP configurations were applied to each of the girders. Each of the test girders performed very well as each of them held a higher capacity than the control girder. The repaired girders 5, 6 and 7 surpassed the control girder's capacity by 10.88%, 15.9% and 11.39%. These results indicate that repairing laterally damaged prestressed concrete bridge girders with CFRP is an effective way to restore the girders flexural capacity.

Download or read book Carbon Fiber Reinforced Polymer Repairs of Impact damaged Prestressed I girders written by Ryan J. Brinkman and published by . This book was released on 2012 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: Three different Carbon Fiber Reinforced Polymer (CFRP) repair techniques are examined to determine how effectively each method can restore the ultimate flexural capacity of impact-damaged prestressed concrete girders. The number of severed prestressing strands and the amount of CFRP repair material applied are varied to create a large repair matrix. The ultimate moment capacity was calculated using the program XTRACT. Capacities were also evaluated using AASHTO and ACI specifications. The prototype girder's geometry is based on an impact-damaged I-girder from a bridge in Eastland County, Texas, which was repaired using CFRP in 2006 using conventional externally bonded CFRP. The CFRP repair methods examined in this study were near surface mounted (NSM) CFRP, externally bonded (EB) CFRP, and bonded post tensioned (bPT) CFRP. The area of the girder available for repair was limited to the bottom soffit for near surface mounted CFRP and bonded post tensioned CFRP; however, the externally bonded CFRP was applied on the bulb as well as the soffit. The range of the repairs examined were approximately 25%, 50%, and 75%, and 100% of the maximum practical amount of CFRP which could be applied based on the girder geometry, ACI guidelines, and manufacturers' recommendations. The geometry of the girder limited the amount of CFRP which could be applied, so the repairs could only completely restore the ultimate girder capacity when very few strands were damaged and the maximum amount of CFRP was used. However, the CFRP techniques were shown effective at restoring some of the lost capacity and thus are an option if only a portion of the lost capacity must be restored. The study also showed that, in some cases, repairs are completely ineffective and the girder capacity is not increased beyond the damaged state. Using the results of this study, engineers can determine when repairing a girder will be effective and the extent to which the repair restores lost capacity.

Download or read book Impact Damage and Repair of AASHTO Type III Girders written by Steven Arthur Olson and published by . This book was released on 1991 with total page 472 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.