Effectiveness of Epoxy-coated Reinforcing Steel - Interim Report

Download Effectiveness of Epoxy-coated Reinforcing Steel - Interim Report PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 94 pages
Book Rating : 4.:/5 (614 download)

DOWNLOAD NOW!


Book Synopsis Effectiveness of Epoxy-coated Reinforcing Steel - Interim Report by :

Download or read book Effectiveness of Epoxy-coated Reinforcing Steel - Interim Report written by and published by . This book was released on 1992 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary function of an epoxy coating is to act as a barrier to prevent corrosion-causing chloride ions and oxygen from reaching steel surfaces. For more than a decade, epoxy-coated reinforcing steel has generally been effective in reducing or preventing chloride-induced corrosion in bridges and other concrete structures. Recently, however, instances of corrosion problems or premature failures in Florida, Oregon and New York have focussed attention on the product and its quality. This report was initiated as a result of the questions raised by these failures. In the first section of the report, a state of the art review of epoxy-coated reinforced steel is presented. It details the research performed on epoxy coating, and the results of this research both in the lab and in the field. As well, the authors highlight several areas to be considered for future investigation. The second section examines the fundamentals of epoxy, and the coating process. It provides an overview of the theory, technology, testing and practice as these presently exist for fusion bonded epoxy coatings on steels. The significance of the tests available for use on epoxy-coated rebars and epoxy-coated pipe is described. The report contains numerous figures.

Performance of Epoxy-coated Reinforcing Steel in Highway Bridges

Download Performance of Epoxy-coated Reinforcing Steel in Highway Bridges PDF Online Free

Author :
Publisher : Transportation Research Board
ISBN 13 : 9780309053709
Total Pages : 164 pages
Book Rating : 4.0/5 (537 download)

DOWNLOAD NOW!


Book Synopsis Performance of Epoxy-coated Reinforcing Steel in Highway Bridges by : Kenneth C. Clear

Download or read book Performance of Epoxy-coated Reinforcing Steel in Highway Bridges written by Kenneth C. Clear and published by Transportation Research Board. This book was released on 1995 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Effectiveness of Epoxy-Coated Reinforced Steel

Download Effectiveness of Epoxy-Coated Reinforced Steel PDF Online Free

Author :
Publisher :
ISBN 13 : 9781895102901
Total Pages : 94 pages
Book Rating : 4.1/5 (29 download)

DOWNLOAD NOW!


Book Synopsis Effectiveness of Epoxy-Coated Reinforced Steel by : Kenneth C. Clear

Download or read book Effectiveness of Epoxy-Coated Reinforced Steel written by Kenneth C. Clear and published by . This book was released on 1992-11-01 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary function of an eposy-coating is to act as a barrier to prevent corrosion-causing chloride ions and oxygen from reaching steel surfaces. For more than a decade, epoxy-coated reinforcing steel has generally been effective in reducing or preventing chloride-induced corrosion in bridges and other concrete structures. Recently, however, instances of corrosion problems or premature failures in Florida, Oregon and New York have focussed attention on the product and its quality. This report was initiated as a result of the questions raised by these failures.

Summary Report on the Performance of Epoxy-coated Reinforcing Steel in Virginia

Download Summary Report on the Performance of Epoxy-coated Reinforcing Steel in Virginia PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 32 pages
Book Rating : 4.:/5 (72 download)

DOWNLOAD NOW!


Book Synopsis Summary Report on the Performance of Epoxy-coated Reinforcing Steel in Virginia by : Richard E. Weyers

Download or read book Summary Report on the Performance of Epoxy-coated Reinforcing Steel in Virginia written by Richard E. Weyers and published by . This book was released on 2006 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: From 1992 to 2006, the Virginia Transportation Research Council and its contract researchers conducted a long-term systematic series of investigations to evaluate the corrosion protection effectiveness of epoxy-coated reinforcement (ECR) and to identify and recommend the best and most cost-effective corrosion protection system for Virginia bridge decks. This report summarizes this research and subsequent efforts to implement alternative reinforcement. The work was conducted, and is reported, in this general order: review of historical performance of ECR, ECR performance in solutions and concrete, and preliminary field investigations; investigation of field performance of bridge decks built with ECR; assessment of alternative corrosion protection methods; development of probabilistic service life models for bridge decks and laboratory assessment of ECR cores extracted from bridge decks to determine service life extension; efforts to implement alternative reinforcement. The series of studies demonstrated that the epoxy coating on ECR naturally degrades in the highly alkaline moist environment within concrete. The subsequent loss of bond, coupled with the inevitable flaws in the coating induced by construction, leads to an estimated service life benefit of ECR of as little as 3 to 5 years. Further, non-critical decks, beams, and substructure elements not exposed to marine environments, particularly on secondary and rural routes, can be cost-effectively constructed and maintained using low-permeability concrete and black reinforcing bar. However, because the Federal Highway Administration requires the use of corrosion-resistant reinforcement, and because ECR cannot provide adequate corrosion protection for structures designed for a 100-year+ service life as currently recommended by FHWA, the report recommends that the Virginia Department of Transportation amend its specifications regarding the use of ECR to require the use of corrosion-resistant metallic reinforcing bars such as MMFX2, stainless steel clad, and solid stainless steel.

Evaluation of Epoxy-coated Reinforcing Steel

Download Evaluation of Epoxy-coated Reinforcing Steel PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 28 pages
Book Rating : 4.:/5 (1 download)

DOWNLOAD NOW!


Book Synopsis Evaluation of Epoxy-coated Reinforcing Steel by : Wallace T. McKeel

Download or read book Evaluation of Epoxy-coated Reinforcing Steel written by Wallace T. McKeel and published by . This book was released on 1993 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Virginia's first installation of epoxy-coated reinforcing steel, which was opened to traffic in 1977, was evaluated during construction and through 13 years of service. It was apparent at the time of construction that the integrity of the coating application did not meet the requirements of the specifications There were many flaws and holidays in the coatings on all of the bars, and patching with a liquid epoxy compound was not effective. Although the applicability of the findings, which are based on an application that does not represent the best practice, may be limited, useful information on the durability of the coated steel and its role in protecting the deck was developed. It was found that the coated reinforcement was exposed to relatively high chloride concentrations at transverse cracks in the decks early in the life of the structures, but the decks remained in good condition throughout the evaluation period. It was concluded that despite the poor coatings, the coated reinforcing steel contributed to the deck's durability by providing enhanced protection at critical cracked sections. Rebars taken from deck cores showed no signs of rusting, although the steel had a dull dark gray finish that may be underfilm corrosion. No debonding of the coating was evident.

Effectiveness of Epoxy Coating Nitoprime Zincrich as Corrosion Protection Method for Reinforcing Steel

Download Effectiveness of Epoxy Coating Nitoprime Zincrich as Corrosion Protection Method for Reinforcing Steel PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 172 pages
Book Rating : 4.:/5 (975 download)

DOWNLOAD NOW!


Book Synopsis Effectiveness of Epoxy Coating Nitoprime Zincrich as Corrosion Protection Method for Reinforcing Steel by : S.Amutha Subramaniam

Download or read book Effectiveness of Epoxy Coating Nitoprime Zincrich as Corrosion Protection Method for Reinforcing Steel written by S.Amutha Subramaniam and published by . This book was released on 2005 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: The principal cause of degradation of steel reinforced structures is corrosion damage to the rebar embedded in the concrete. The two most common causes of reinforcement corrosion are chloride ions and carbonation. The scale of this problem has reached alarming proportions in various parts of the world. Thus, a lot of money being spent on the rehabilitation of concrete structures i.e. bridges, marine structures etc. In realizing this crucial situation, the corrosion protection methods were emphasized widely in the past. However, the proposed methods somehow failed to be implemented widely due to various factors. Hence this project is trying to look into the potential corrosion protection method on reinforcement steel. Laboratory tests were carried out using small reinforced concrete beam specimens exposed to different corrosive environment namely tap water, chloride, tap water accelerated, marine accelerated and acidic accelerated. Out of total 10 numbers of specimens, 5 specimens contain reinforcement painted with epoxy-coating (Nitoprime Zincrich) having coating thickness of 40 11m. Acceleration tests were carried out on 60% of the specimens to expedite the various environmental effects on the specimens. From the study, it is apparent that coating the reinforcement prior to placing inside concrete plays a key role in protecting the reinforcement from corrosion. However, one needs to study the environment prior to choosing the suitable coating material.

Effect of Cathodic Protection on Epoxy-coated Rebar

Download Effect of Cathodic Protection on Epoxy-coated Rebar PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 66 pages
Book Rating : 4.:/5 (1 download)

DOWNLOAD NOW!


Book Synopsis Effect of Cathodic Protection on Epoxy-coated Rebar by : S. Ray Taylor

Download or read book Effect of Cathodic Protection on Epoxy-coated Rebar written by S. Ray Taylor and published by . This book was released on 1998 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: Epoxy coating is widely used to mitigate the access of chloride ions to the surface of a rebar. However, corrosion at the point of physical defects in the coating necessitates rehabilitation. Based on its effectiveness in mitigating corrosion of uncoated rebars, we examined cathodic protection (CP) as a method for rehabilitating epoxy-coated rebars (ECR). Although it is well established that cathodic polarization of epoxy coatings on steel in aqueous conditions leads to disbondment of the coating, neither the conditions that lead to this phenomenon nor the actual occurrence of this disbondment process has been determined for ECR in concrete. Since the integrity of the bond between the rebar and the concrete is essential to the composite strengthening by the rebar, the relationships among CP, the integrity of the epoxy coating, and the strength of the rebar/concrete bond must be investigated. The objectives of this study were (1) to determine if CP can effectively mitigate corrosion of coated rebar without adversely affecting the rebar/concrete interface, and (2) to examine the effect of cathodic polarization on the disbonding characteristics of the epoxy coating/rebar interface in concrete. Fifty-five samples of No. 5 ECR with coating defects were exposed to CP. Tensile loading produced splitting failures of all samples. This mode of failure allows greater sensitivity to the contributions of concrete/rebar adhesion and friction than do pullout failures. All electrochemical tests indicated that the cathodic polarization levels and times of application used in this study were effective in preventing corrosion of embedded ECR. An important finding was that the CP protection levels and times had no effect on the splitting failure characteristics based on comparisons of 95 percent confidence intervals. Multiple parameters within the electrochemical impedance spectra indicated that the epoxy coating was delaminating from the steel at the periphery of the defects. This phenomenon was verified in a post mortem analysis of the samples using scanning electron microscopy. The immediate significance of this result is that CP current demands could increase over time. Even though the levels of delamination in this study did not affect mechanical performance, a protective CP level that does not induce film delamination should be explored.

Parameters Governing the Corrosion Protection Efficiency of Fusion-bonded Epoxy Coatings on Reinforcing Steel

Download Parameters Governing the Corrosion Protection Efficiency of Fusion-bonded Epoxy Coatings on Reinforcing Steel PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 67 pages
Book Rating : 4.:/5 (19 download)

DOWNLOAD NOW!


Book Synopsis Parameters Governing the Corrosion Protection Efficiency of Fusion-bonded Epoxy Coatings on Reinforcing Steel by :

Download or read book Parameters Governing the Corrosion Protection Efficiency of Fusion-bonded Epoxy Coatings on Reinforcing Steel written by and published by . This book was released on 2008 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this study was to investigate various epoxy coating and exposure parameters to determine their effects on the corrosion of reinforcing steel. The parameters investigated were: chloride content at the bar depth, coated bar corroded area, corrosion product color under the coating, epoxy coating adhesion, coating color, coating damage (holidays and holes), coating thickness, TGA, DSC and EDS analysis and SEM coating cracking investigation. This study demonstrated that the ECR coating samples extracted from concrete exhibited extensive cracking compared to the new ECR samples in which the coating cracking was limited to only one sample. The coating cracking correlated with the amount of chloride at bar level, residual adhesion of the epoxy to the steel surface, and the percent moisture in the coating. The coating cracking is also related to the change in color of the epoxy and indicates that the epoxy coating degradation in concrete influences the surface condition of the coating. The DSC results showed that both the extracted epoxy coating samples as well as new samples are not fully cured during the manufacturing process. Additionally, the extracted epoxy coated samples investigated presented significant permanent adhesion loss with little or no epoxy coating residue present on the bar surface, while the EDS analysis showed that once adhesion is lost, corrosion will proceed unimpeded under the coating even in the absence of chlorides. The parameters that presented a direct correlation with the observed corrosion activity were the number of holidays and the number of damaged areas per unit length of bar. The results also show a distinct loss of quality control in the handling and possibly storage of new coated bars. The new ECR samples had significantly higher damage density than the samples extracted from concrete, while there was no change in the number of holidays and cure condition.

Long-term Performance of Epoxy-coated Reinforcing Steel in Heavy Salt-contaminated Concrete

Download Long-term Performance of Epoxy-coated Reinforcing Steel in Heavy Salt-contaminated Concrete PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 136 pages
Book Rating : 4.:/5 (1 download)

DOWNLOAD NOW!


Book Synopsis Long-term Performance of Epoxy-coated Reinforcing Steel in Heavy Salt-contaminated Concrete by : Seung-Kyoung Lee

Download or read book Long-term Performance of Epoxy-coated Reinforcing Steel in Heavy Salt-contaminated Concrete written by Seung-Kyoung Lee and published by . This book was released on 2004 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Corrosion of Steel in Concrete Structures

Download Corrosion of Steel in Concrete Structures PDF Online Free

Author :
Publisher : Woodhead Publishing
ISBN 13 : 0323851320
Total Pages : 400 pages
Book Rating : 4.3/5 (238 download)

DOWNLOAD NOW!


Book Synopsis Corrosion of Steel in Concrete Structures by : Amir Poursaee

Download or read book Corrosion of Steel in Concrete Structures written by Amir Poursaee and published by Woodhead Publishing. This book was released on 2023-02-20 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Essential reading for researchers, practitioners, and engineers, this book covers not only all the important aspects in the field of corrosion of steel reinforced concrete but also discusses new topics and future trends. Theoretical concepts of corrosion of steel in concrete structures, the variety of reinforcing materials and concrete, including stainless steel and galvanized steel, measurements and evaluations, such as electrochemical techniques and acoustic emission, protection and maintenance methods, and modelling, latest developments, and future trends in the field are discussed. Comprehensive coverage of the corrosion of steel bars in concrete, investigating the range of reinforcing materials, and types of concrete Introduces the latest measuring methods, data collection, and advanced modeling techniques Second edition covers a range of new, emerging topics such as the concept of chloride threshold value, concrete permeability and chloride diffusion, the role of steel microstructure, and innovations in corrosion detection devices

The Performance of Epoxy Coated Reinforcement:

Download The Performance of Epoxy Coated Reinforcement: PDF Online Free

Author :
Publisher :
ISBN 13 : 9780779470778
Total Pages : 29 pages
Book Rating : 4.4/5 (77 download)

DOWNLOAD NOW!


Book Synopsis The Performance of Epoxy Coated Reinforcement: by :

Download or read book The Performance of Epoxy Coated Reinforcement: written by and published by . This book was released on 2005 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: In reinforced concrete construction, epoxy coated reinforcement (ECR) was introduced in the 1970s to provide a physical barrier to chlorides at the concrete-steel interface. The Ontario Ministry of Transportation has used ECR in bridges & other components since 1979. In response to reports of corrosion of ECR in structures in Florida and other concerns, the Ministry initiated a detailed investigation in 1997 of the barrier walls of five ECR-reinforced highway bridges constructed in 1979 to assess the effectiveness of the epoxy coating in preventing chloride-induced corrosion. This paper updates the Ministry's investigations since the 1997 barrier wall study and documents significant findings with respect to ECR performance, including its performance in comparison to that of black steel reinforcement. It discusses various considerations related to the use of ECR and factors affecting its performance, such as coating quality, repair of structures constructed with ECR, and corrosion protection strategies.

Corrosion Evaluation of Epoxy-coated, Metallic-clad and Solid Metallic Reinforcing Bars in Concrete

Download Corrosion Evaluation of Epoxy-coated, Metallic-clad and Solid Metallic Reinforcing Bars in Concrete PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 148 pages
Book Rating : 4.3/5 (555 download)

DOWNLOAD NOW!


Book Synopsis Corrosion Evaluation of Epoxy-coated, Metallic-clad and Solid Metallic Reinforcing Bars in Concrete by : David B. McDonald

Download or read book Corrosion Evaluation of Epoxy-coated, Metallic-clad and Solid Metallic Reinforcing Bars in Concrete written by David B. McDonald and published by . This book was released on 1998 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes the work conducted from 1993 to 1998 to develop cost-effective "new breeds" of organic, inorganic, ceramic and metallic coatings, as well as metallic alloys that can be utilized on or as reinforcement for embedment in portland cement concrete. As part of the study, 12 different bar types were tested in concrete: black bars, 3 bendable and 3 nonbendable epoxies, Type 304 and Type 316 stainless steel, copper-clad, galvanized and spray metallic-clad reinforcing. Measurements of macrocell voltages, half-cell potentials, electrochemical impedance spectroscopy, linear polarization and mat-to-mat resistances were used in conjunction with visual observations to determine the effectiveness of each system.

Long-Term Performance of Epoxy-Coated Reinforcing Steel in Heavy Salt-Contaminated Concrete

Download Long-Term Performance of Epoxy-Coated Reinforcing Steel in Heavy Salt-Contaminated Concrete PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 130 pages
Book Rating : 4.:/5 (614 download)

DOWNLOAD NOW!


Book Synopsis Long-Term Performance of Epoxy-Coated Reinforcing Steel in Heavy Salt-Contaminated Concrete by :

Download or read book Long-Term Performance of Epoxy-Coated Reinforcing Steel in Heavy Salt-Contaminated Concrete written by and published by . This book was released on 2004 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes results obtained from a long-term natural weathering exposure testing of the remaining 31 post-Southern Exposure (SE) test slabs that contained epoxy-coated reinforcing bar (ECR), black bars, and stainless steel bars and were not autopsied during the 1993-1998 Federal Highway Administration (FHWA) research project. The test slabs had been exposed to the very aggressive SE test, which involved alternating wetting with 15 weight percent NaCl solution and air drying cycles for 96 weeks. The test results confirmed that the black bars produced the highest mean macrocell current density (least corrosion resistant) among various combinations of test variables regardless of slab configuration and the stainless steel bars exhibited negligible mean macrocell current density. The performance of straight top-mat ECRs varied from 7 to 40 percent of the highest black bar case, as measured by macrocell current density, depending on the size of the initial coating damage and the type of bar in the bottom mat. ECR used in the top mat alone reduced the corrosion susceptibility to at least 50 percent of the black bar case, even when it contained coating damage and was connected to the black bar bottom mat. If straight ECRs in the top mat were connected to ECRs in the bottom mat, the mean macrocell current density was no greater than two percent of the highest black bar case and approached the corrosion resistant level of stainless steel reinforcement. Autopsy of ECR slabs exhibiting negligible macrocell current density revealed excellent condition with no sign of corrosion. However, ECRs exhibiting high macrocell current densities showed coating deterioration and exhibited numerous hairline cracks and/or blisters in conjunction with reduced adhesion, coating disbondment (permanent loss of adhesion) and underlying steel corrosion. The test results of present and the earlier FHWA studies indicate that adhesion appeared to be a poor indicator of long-term performance of the coated bars in chloride contaminated concrete and it is concluded that there is no direct relationship between loss of adhesion and the effectiveness of ECR to mitigate corrosion.

Galvanized Steel Reinforcement in Concrete

Download Galvanized Steel Reinforcement in Concrete PDF Online Free

Author :
Publisher : Elsevier
ISBN 13 : 0080472834
Total Pages : 316 pages
Book Rating : 4.0/5 (84 download)

DOWNLOAD NOW!


Book Synopsis Galvanized Steel Reinforcement in Concrete by : Stephen Yeomans

Download or read book Galvanized Steel Reinforcement in Concrete written by Stephen Yeomans and published by Elsevier. This book was released on 2004-11-26 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reinforced concrete is one of the most widely used modern materials of construction. It is comparatively cheap, readily available, and suitable for a variety of building and construction applications. Galvanized Steel Reinforcement in Concrete provides a detailed resource covering all aspects of this important material. Both servicability and durability aspects are well covered, with all the information needed maximise the life of buildings constructed from it. Containing an up-to-date and comprehensive collection of technical information and data from world renound authors, it will be a valuable source of reference for academics, researchers, students and professionals alike. Provides information vital to prolong the life of buildings constructed from this versatile material Brings together a disparate body of knowledge from many parts of the world into a concise and authoritative text Containing an up-to-date and comprehensive collection of technical information

Epoxy-coated Reinforcement

Download Epoxy-coated Reinforcement PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 104 pages
Book Rating : 4.:/5 (222 download)

DOWNLOAD NOW!


Book Synopsis Epoxy-coated Reinforcement by : Jerzy Zemajtis

Download or read book Epoxy-coated Reinforcement written by Jerzy Zemajtis and published by . This book was released on 1996 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report is a historical performance review of epoxy-coated reinforcement. The information in this report is presented in chronological order starting from the early 1970's, when the first bridge with epoxy-coated reinforcement was built, and ending with the presentation at the 1993 TRB sessions, where findings from the latest research investigations were revealed. The report includes background information on fundamental applications of epoxy-coated reinforcing steel. Major laboratory studies, which addressed corrosion resistance and bond strength issues, are presented. Field investigations of meaningful structures with successful application of epoxy -coated reinforcing steel as well as structures with total failure of epoxy-coated reinforcement are also presented. The report also includes transcripted presentations, from the 1993 TRB sessions, which addressed quality control, adhesion characteristics, and other factors associated with long-term performance of epoxy-coated reinforcing steel. Conclusions from the laboratory and field investigations, as well as from the presentations of 1993 TRB sessions are presented.

Improving Development Characteristics of Reinforcing Bars

Download Improving Development Characteristics of Reinforcing Bars PDF Online Free

Author :
Publisher : American Society of Civil Engineers
ISBN 13 :
Total Pages : 104 pages
Book Rating : 4.3/5 (91 download)

DOWNLOAD NOW!


Book Synopsis Improving Development Characteristics of Reinforcing Bars by : Civil Engineering Research Foundation

Download or read book Improving Development Characteristics of Reinforcing Bars written by Civil Engineering Research Foundation and published by American Society of Civil Engineers. This book was released on 1994 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes the development and implications of a new concrete reinforcing bar with significantly improved bond strength.

Corrosion Protection Service Life of Epoxy-coated Reinforcing Steel in Virginia Bridge Decks

Download Corrosion Protection Service Life of Epoxy-coated Reinforcing Steel in Virginia Bridge Decks PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 63 pages
Book Rating : 4.:/5 (532 download)

DOWNLOAD NOW!


Book Synopsis Corrosion Protection Service Life of Epoxy-coated Reinforcing Steel in Virginia Bridge Decks by : Michael Carey Brown

Download or read book Corrosion Protection Service Life of Epoxy-coated Reinforcing Steel in Virginia Bridge Decks written by Michael Carey Brown and published by . This book was released on 2003 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: The corrosion protection service life extension provided by epoxy-coated reinforcement (ECR) was determined by comparing ECR and bare steel bars from 10 Virginia bridge decks built between 1981 and 1995. The objective was to determine the corrosion protection service life time extension provided by ECR field specimens with various degrees of coating adhesion: disbonded, partially disbonded, and wholly bonded coatings. The size and length distributions of cracks in Virginia bridge decks were investigated to assess the frequency and severity of cracks. Correlation of cracks with chloride penetration was used to characterize the influence of cracking on deck deterioration. Cracks influence the rate of chloride penetration, but the frequency and width distributions of cracks indicate that cracks are not likely to shorten the overall service life of most bridge decks in Virginia. Altogether, 141 drilled cores, 102 mm (4 inches) in diameter, were employed in this study. For each of the decks built with ECR, 10 to 12 cores were drilled through a top reinforcing bar adjacent to the previous study core locations. In addition, approximately 3 cores were drilled through a top reinforcing bar at a surface crack location. Laboratory testing involved nondestructive monitoring using advanced electrochemical techniques to periodically assess the corrosion state of the steel bars during cyclic exposure to chloride-rich solution over 36 months of treatment. Time of corrosion initiation and time of cracking (where applicable), as well as chloride content of the concrete before and after treatment, were used in the analysis. Analysis of the epoxy coating after treatment showed the presence of micro cracks in the surface of some coatings, and moisture uptake and glass transition temperatures, as related to curing of the coatings, were investigated. Less than 25 percent of all Virginia bridge decks built under specifications in place since 1981 is projected to corrode sufficiently to require rehabilitation within 100 years, regardless of bar type. The corrosion service life extension attributable to ECR in bridge decks was found to be approximately 5 years beyond that of bare steel and, therefore, ECR is not a cost-effective method of corrosion prevention for bridge decks. Deleting the requirement for ECR in decks would save Virginia approximately $845,000 per year.