Download or read book Corrosion Protection Performance of Epoxy coated Reinforcing Bars written by José Antonio Pincheira and published by . This book was released on 2008 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main purpose of this investigation was to conduct an in-depth study to determine the level of corrosion protection offered by epoxy-coated bars in four bridge decks in the Minneapolis/St. Paul, MN metropolitan area. The bridges studied were built between 1973 and 1978 and all decks had a top mat built with epoxy-coated bars. The bottom mat was epoxy-coated in only one deck whereas black steel was used for the bottom mat in the other bridges. These bridges had been assessed in 1996 and thus, the present study is a follow up investigation to obtain data and assess the field performance of epoxy-coated bars over a period of approximately 30 years. The investigation included field inspection and surveys of the decks, as well as laboratory tests of concrete core and bar samples. After 30 years of service, the overall condition of the epoxy-coated bars is good to very good, with no or modest levels of corrosion activity. In only one bridge, corrosion activity appears to be moderate to severe. The majority of corroded bars were found near joints or at crack locations. The amount of delamination in all decks is very low.

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:

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.

Download or read book Corrosion Protection of Reinforcing Steels written by fib Fédération internationale du béton and published by fib Fédération internationale du béton. This book was released on 2009-01-01 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt: It has long been recognised that corrosion of steel is extremely costly and affects many industry sectors, including concrete construction. The cost of corrosion of steel reinforcement within concrete is estimated at many billions of dollars worldwide. The corrosion of steel reinforcement represents a deterioration of the steel which in turn detrimentally affects its performance and therefore that of the concrete element within which it has been cast. A great amount of work has been undertaken over the years concerning the prevention of corrosion of steel, including the application of coatings, which has included the study of the process of corrosion itself, the properties of reinforcing steels and their resistance to corrosion as well as the design of structures and the construction process. The objective of fib Bulletin 49 is to provide readers with an appreciation of the principles of corrosion of reinforcing steel embedded in concrete and to describe the behaviour of particular steels and their coatings as used to combat the effects of such corrosion. These include galvanised reinforcement, epoxy coated reinforcement, and stainless reinforcing steel. It also provides information on the relative costs of the materials and products which it covers. It does not deal with structure design or the process of construction or with the post-construction phase of structure management including repair. It is hoped that it will nevertheless increase the understanding of readers in the process of corrosion of reinforcing steels and the ability of key materials and processes to reduce its harmful effects.

Download or read book Corrosion Protection Performance of Corrosion Inhibitors and Epoxy coated Reinforcing Steel in a Simulated Concrete Pore Water Solution written by Wioleta A. Pyć and published by . This book was released on 1998 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: We used a simulated concrete pore water solution to evaluate the corrosion protection performance of concrete corrosion-inhibiting admixtures and epoxy-coated reinforcing bars (ECR). We evaluated three commercial corrosion inhibitors, ECR from three coaters removed from job sites, one ECR shipped directly from the coater's plant, and one ECR removed from a job site plus a corrosion inhibitor. The corrosion inhibitors were calcium nitrite, an aqueous mixture of esters and amines, and a mixture of alcohol and amine. Corrosion protection performance was based on the amount of visually observed corroded surface area. For bare steel tested with and without corrosion inhibitors, corrosion increased with increasing chloride concentration, and specimens saturated with oxygen were more corroded than specimens saturated with breathing air. The amount of corrosion over the 90-day test period was controlled by the amount of oxygen in solution at the higher chloride concentrations. The ester-amine and alcohol-amine did not inhibit corrosion. Calcium nitrite inhibited corrosion at all levels of chloride concentration. For ECR, corrosion occurred both at sites where the coating was damaged and underneath the coating. Coating debondment was greatest in pore water solutions containing chloride. The least coating debondment and corrosion occurred in the solution containing calcium nitrite and the ECR shipped directly from the manufacturer. Coating debondment and corrosion of ECR are directly related to the amount of damage as holes; mashed, dented, and cracked areas; and holidays. The researchers recommend that the developed test method be adopted as a standard test for concrete corrosion inhibitors and that calcium nitrite remain the only concrete corrosion inhibitor approved for use in Virginia.

Download or read book Field Performance of Epoxy coated Reinforcing Steel in Virginia Bridge Decks written by and published by . This book was released on 2000 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study, the corrosion protection performance of epoxy-coated reinforcing steel (ECR) was evaluated using approximately 250 concrete cores from 18 bridge decks in Virginia. The decks were 2 to 20 years old at the time of the investigation. The deck field inspections included a crack survey and cover depth determination in the right traffic lane. A maximum of 12 cores with the top reinforcement randomly located in the lowest 12th percentile cover depth were taken from each bridge deck. Because of the safety concerns associated with taking cores from the lower steel mat, and to minimize damage to the bridge, a maximum of only 3 cores were taken through the truss bars. The laboratory evaluation of the concrete cores included a visual examination and a determination of the carbonation depth, moisture content, absorption, percent saturation, and chloride content at a 13-mm depth. The rapid chloride permeability test was also performed for the surface and base concrete on samples obtained from the cores taken through the truss bars to determine chloride permeability. The ECR inspection consisted of a visual examination, a damage evaluation, and a determination of coating thickness and adhesion. The condition of the steel underneath the epoxy coating was also evaluated. Adhesion loss of the epoxy coating to the steel surface was detected in all but one deck that was 4 years old and older. The epoxy coatings were debonding from the reinforcing bars. Whereas a bonded coating can be expected to protect the steel, a debonded coating allows chlorides, moisture, and oxygen to reach the steel and initiate a rapid corrosion mechanism. Reinforcing bars in various stages of adhesion loss showed visible signs of a corrosion process underneath the coating, suggesting that ECR will provide little or no additional service life for concrete bridge decks in comparison to bare steel. Other systems that will provide longer protection against chloride-induced corrosion of the reinforcing steel with a higher degree of reliability should be considered.

Download or read book Methods of Corrosion Protection and Durability of Concrete Bridge Decks Reinforced with Epoxy coated Bars Phase I written by Lisa M. Samples and published by . This book was released on 1999 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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:

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

Download or read book Time to corrosion of Reinforcing Steel in Concrete Slabs written by Yash Paul Virmani and published by . This book was released on 1983 with total page 71 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thirty-one relatively large reinforced concrete slabs were fabricated in 1980 using either non-specification epoxy-coated reinforcing steel or calcium nitrite admixture with black (uncoated) steel. Their performance is compared with uncoated steel in concrete without admixtures. The slabs were placed in two lifts: the bottom lift consisted of a bottom mat of reinforcing steel in chloride-free concrete; and a top lift consisting of the top-mat rebars in concrete contaminated with various quantities of sodium chloride. All the electrical connections between the reinforcing mats were made exterior to the slabs so that the corrosion current flow could be monitored. A worst case type of research design was used by specifying poor quality concrete, nonspecification epoxy-coated rebars, and good electrical coupling between the rebar mats. After curing, the slabs were mounted above ground and exposed to the environment of the Washington, D.C. location.

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.

Download or read book Field Investigation of the Corrosion Protection Performance of Bridge Decks and Piles Constructed with Epoxy coated Reinforcing Steel in Virginia written by and published by . This book was released on 1997 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Epoxy coated Steel Reinforcing Bars written by Concrete Reinforcing Steel Institute and published by . This book was released on 2004 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Eco efficient Repair and Rehabilitation of Concrete Infrastructures written by Fernando Pacheco-Torgal and published by Elsevier. This book was released on 2024-03-22 with total page 457 pages. Available in PDF, EPUB and Kindle. Book excerpt: Eco-efficient Repair and Rehabilitation of Concrete Infrastructures, Second Edition provides an updated state-of-the-art review on the latest advances in this important research field. The first section is brought fully up-to-date and focuses on deterioration assessment methods. Section two contains brand new chapters on innovative concrete repair and rehabilitation materials including: fly ash-based alkali-activated repair materials for concrete exposed to aggressive environments; repairing concrete structures with alkali-activated metakaolin mortars; concrete with micro encapsulated self-healing materials; concrete repaired with bacteria; concrete structures repaired with engineered cementitious composites; concrete repaired by electrodeposition; the assessment of concrete after repair operations and durability of concrete repair. The final section has also been amended to include six new chapters on design, Life-cycle cost analysis and life-cycle assessment. These chapters include maintenance strategies for concrete structures; a comparison of different repair methods; life cycle assessment of the effects of climate change on bridge deterioration; life-cycle-cost benefits of cathodic protection of concrete structures; life-cycle cost analyses for concrete bridges exposed to chlorides and life-cycle analysis of repair of concrete pavements. The book will be an essential reference resource for materials scientists, civil and structural engineers, architects, structural designers and contractors working in the construction industry. Covers the latest research findings on eco-efficient repair and rehabilitation of concrete infrastructures Provides comprehensive coverage from damage detection and assessment, to repair strategies and structural health monitoring Presents a diverse author base that offers insights on construction practice and employed technologies worldwide Includes an entire section on NDT, innovative repair, and rehabilitation materials, as well as case studies on lifecycle cost analysis and lifecycle assessment

Download or read book Nonmetallic Coatings for Concrete Reinforcing Bars written by James R. Clifton and published by . This book was released on 1975 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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.

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