A Comparison of the Corrosion Performance of Uncoated, Galvanized, and Epoxy Coated Reinforcing Steel in Concrete Bridge Decks

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ISBN 13 :
Total Pages : 85 pages
Book Rating : 4.:/5 (355 download)

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Book Synopsis A Comparison of the Corrosion Performance of Uncoated, Galvanized, and Epoxy Coated Reinforcing Steel in Concrete Bridge Decks by : Ronnie L. McCrum

Download or read book A Comparison of the Corrosion Performance of Uncoated, Galvanized, and Epoxy Coated Reinforcing Steel in Concrete Bridge Decks written by Ronnie L. McCrum and published by . This book was released on 1995 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Performance of Epoxy-coated Reinforcing Steel in Highway Bridges

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

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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:

Evaluation of Multiple Corrosion Protection Systems for Reinforced Concrete Bridge Decks

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Publisher :
ISBN 13 :
Total Pages : 522 pages
Book Rating : 4.:/5 (851 download)

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Book Synopsis Evaluation of Multiple Corrosion Protection Systems for Reinforced Concrete Bridge Decks by : Matthew O'Reilly

Download or read book Evaluation of Multiple Corrosion Protection Systems for Reinforced Concrete Bridge Decks written by Matthew O'Reilly and published by . This book was released on 2011 with total page 522 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The performance of corrosion protection systems for reinforcing steel in concrete is evaluated. In addition to conventional and conventional epoxy-coated reinforcement, the corrosion protection systems tested include epoxy coatings with improved adhesion to the underlying steel, conventional and conventional epoxy-coated reinforcement used in conjunction with concrete containing one of three corrosion inhibitors, DCI-S, Rheocrete 222+, or Hycrete, epoxy-coated reinforcement with a microencapsulated calcium nitrite primer, multiple-coated reinforcement with a layer of zinc between the epoxy and steel, and pickled 2205 duplex stainless steel. The systems are evaluated using bench-scale and field tests. Two bridges in Kansas, cast with 2205 stainless steel, are monitored using corrosion potential mapping. Epoxy-coated and multiplecoated bars are evaluated to determine the effect of corrosion loss and time on the disbondment of the epoxy coating. Conventional, galvanized, and epoxy-coated reinforcement are evaluated using impressed current to determine the corrosion loss required to crack concrete for each system. A finite element model is developed to represent general and localized corrosion, and the results are used to develop a relationship between concrete cover, bar diameter, and area of bar corroding, and the corrosion loss required to crack concrete. An analysis of pore solutions expressed from cement pastes containing corrosion inhibitors is performed, with pH and selected ion concentrations measured from solutions collected one and seven days after casting. The results obtained from bench-scale and field test specimens are used to estimate cost effectiveness for each system under a 75-year service life. The results show epoxy coatings significantly reduce the corrosion rate compared to conventional reinforcement. Corrosion inhibitors significantly reduce corrosion rates in uncracked concrete. In cracked concrete, corrosion inhibitors also reduce corrosion rates, but their relative effectiveness is reduced. Specimens containing Hycrete exhibit the lowest corrosion rates; however, field specimens containing Hycrete also show signs of scaling. Epoxies with improved adhesion exhibit no improvement over conventional epoxy-coated reinforcement in terms of corrosion rate or disbondment of the epoxy coating. Multiple-coated reinforcement exhibits significantly less disbondment than epoxy-coated reinforcement. Pickled 2205 reinforcement exhibits the least corrosion among all systems tested. Testing of conventional and galvanized reinforcement indicates galvanized reinforcement requires more than twice as much corrosion loss to crack the surrounding concrete compared to conventional reinforcement."--Technical report documentation page.

Corrosion Protection of Reinforcing Steels

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Publisher : fib Fédération internationale du béton
ISBN 13 : 2883940894
Total Pages : 123 pages
Book Rating : 4.8/5 (839 download)

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Book Synopsis Corrosion Protection of Reinforcing Steels by : fib Fédération internationale du béton

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.

Methods of Corrosion Protection and Durability of Concrete Bridge Decks Reinforced with Epoxy-coated Bars - Phase I

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Publisher :
ISBN 13 :
Total Pages : 276 pages
Book Rating : 4.:/5 (1 download)

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Book Synopsis Methods of Corrosion Protection and Durability of Concrete Bridge Decks Reinforced with Epoxy-coated Bars - Phase I by : Lisa M. Samples

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:

Investigation of Field Corrosion Performance and Bond/Development Length of Galvanized Reinforcing Steel

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Publisher :
ISBN 13 :
Total Pages : 39 pages
Book Rating : 4.:/5 (899 download)

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Book Synopsis Investigation of Field Corrosion Performance and Bond/Development Length of Galvanized Reinforcing Steel by : Phares Brent

Download or read book Investigation of Field Corrosion Performance and Bond/Development Length of Galvanized Reinforcing Steel written by Phares Brent and published by . This book was released on 2014 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: In reinforced concrete systems, ensuring that a good bond between the concrete and the embedded reinforcing steel is critical to long-term structural performance. Without good bond between the two, the system simply cannot behave as intended. The bond strength of reinforcing bars is a complex interaction between localized deformations, chemical adhesion, and other factors. Coating of reinforcing bars, although sometimes debated, has been commonly found to be an effective way to delay the initiation of corrosion in reinforced concrete systems. For many years, the standard practice has been to coat reinforcing steel with an epoxy coating, which provides a barrier between the steel and the corrosive elements of water, air, and chloride ions. Recently, there has been an industry-led effort to use galvanizing to provide the protective barrier commonly provided by traditional epoxy coatings. However, as with any new structural product, questions exist regarding both the structural performance and corrosion resistance of the system. In the fall of 2013, Buchanan County, Iowa constructed a demonstration bridge in which the steel girders and all internal reinforcing steel were galvanized. The work completed in this project sought to understand the structural performance of galvanized reinforcing steel as compared to epoxy-coated steel and to initiate a long-term corrosion monitoring program. This work consisted of a series of controlled laboratory tests and the installation of a corrosion monitoring system that can be observed for years in the future. The results of this work indicate there is no appreciable difference between the bond strength of epoxy-coated reinforcing steel and galvanized reinforcing steel. Although some differences were observed, no notable difference in either peak load, slip, or failure mode could be identified. Additionally, a long-term monitoring system was installed in this Buchanan County bridge and, to date, no corrosion activity has been identified.

Field Performance of Epoxy-coated Reinforcing Steel in Virginia Bridge Decks

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Publisher :
ISBN 13 :
Total Pages : 38 pages
Book Rating : 4.:/5 (436 download)

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Book Synopsis Field Performance of Epoxy-coated Reinforcing Steel in Virginia Bridge Decks by :

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.

Multiple Corrosion Protection Systems for Reinforced Concrete Bridge Components

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Publisher :
ISBN 13 :
Total Pages : 260 pages
Book Rating : 4.3/5 (555 download)

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Book Synopsis Multiple Corrosion Protection Systems for Reinforced Concrete Bridge Components by :

Download or read book Multiple Corrosion Protection Systems for Reinforced Concrete Bridge Components written by and published by . This book was released on 2011 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: Eleven systems containing epoxy-coated reinforcement (ECR) in combination with another corrosion-protection system are evaluated using the rapid macrocell, southern exposure, cracked beam, linear polarization resistance, and field tests. The systems include bars pretreated with zinc chromate to improve the adhesion between the epoxy and the reinforcing steel, two epoxies with improved adhesion to the reinforcing steel, one inorganic corrosion inhibitor (calcium nitrite), two organic corrosion inhibitors (Rheocrete® 222+ and HycreteTM), an epoxy-coated bar with a primer containing microencapsulated calcium nitrite, three epoxy-coated bars with improved adhesion combined with the corrosion inhibitor calcium nitrite, and multiple-coated (MC) bars with an initial 50-microm (2-mil) coating of 98 percent zinc and 2 percent aluminum followed by a conventional epoxy coating. The systems are compared with conventional uncoated reinforcement and conventional ECR. The coatings on all bars are penetrated to simulate the effects of damage during fabrication and placement in the field. The results presented in this report indicate that the coated bars provide superior corrosion protection to the reinforcing steel and that bars with damaged coatings initiate corrosion at chloride contents within concrete that are several times greater and corrode at rates that are typically two orders of magnitude below those exhibited by conventional reinforcement. Limited additional protection is achieved using bars with the primer coating, MC bars, and concrete containing the corrosion inhibitors calcium nitrite and one of the organic corrosion inhibitors, although the latter resulted in reduced compressive strength and reduced resistance to surface scaling. The differences in costs over a 75-year design life are relatively small for coated bars. Cracks in concrete directly over and parallel to the reinforcement, such as found in bridge decks, result in earlier corrosion initiation and higher corrosion rates than obtained with intact concrete for all systems. Epoxies that provide initially high adhesion to the underlying steel provide no advantage over conventional epoxy coatings. All coated bars that were evaluated exhibited corrosion losses at openings through the coating. A reduction in adhesion between an epoxy coating and the reinforcing steel occurs after a period of exposure to corrosive conditions. This reduction increases with increasing chloride content in the concrete and in the presence of cracks and decreases with the use of corrosion inhibitors, with the use of MC reinforcement, and with electrical isolation of the epoxy-coated bars from each other. Corrosion products form under the coating where adhesion has been reduced. For periods up to five years under exposure conditions representative of those in bridge decks, the reduction in adhesion between an epoxy coating and the reinforcing steel did not affect the rate at which coated bars corrode.

Journal of the American Concrete Institute

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Publisher :
ISBN 13 :
Total Pages : 612 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis Journal of the American Concrete Institute by : American Concrete Institute

Download or read book Journal of the American Concrete Institute written by American Concrete Institute and published by . This book was released on 1976 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Service Life Extension of Virginia Bridge Decks Afforded by Epoxy-Coated Reinforcement

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Publisher :
ISBN 13 :
Total Pages : 13 pages
Book Rating : 4.:/5 (125 download)

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Book Synopsis Service Life Extension of Virginia Bridge Decks Afforded by Epoxy-Coated Reinforcement by : MC. Brown

Download or read book Service Life Extension of Virginia Bridge Decks Afforded by Epoxy-Coated Reinforcement written by MC. Brown and published by . This book was released on 2006 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: A study was conducted on concrete core samples each containing a single top-mat reinforcing steel bar from ten bridge decks in Virginia. Two of the bridges contained conventional, uncoated mild reinforcing steel (Bare), and eight of the bridges were constructed with epoxy-coated reinforcement (ECR). The bridges ranged in age from 4 to 18 years, and were built under same specifications for concrete water-to-cement ratio (w/c) and cover depth. In the laboratory, the subject cores were prepared and corrosion activity was monitored via electrochemical impedance spectroscopy while subject to cyclic ponding of a 3 % NaCl solution over a 22-month exposure period. The relative corrosion performance of the Bare and ECR bars were evaluated, by comparison of the time to corrosion initiation and time to failure, as designated by visible cracking of the concrete cover. A stochastic model was employed, using bootstrap resampling techniques, to project the corrosion protection service life extension provided by epoxy-coated reinforcement as compared to Bare steel for the population of Virginia bridge decks. Less than 25 % of all Virginia bridge decks built under specifications in place since 1981 were 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.

Corrosion of Reinforcing Steel in Concrete

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Publisher : ASTM International
ISBN 13 :
Total Pages : 214 pages
Book Rating : 4./5 ( download)

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Book Synopsis Corrosion of Reinforcing Steel in Concrete by : D. E. Tonini

Download or read book Corrosion of Reinforcing Steel in Concrete written by D. E. Tonini and published by ASTM International. This book was released on 1980 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Evaluation of Multiple Corrosion Protection Systems and Corrosion Inhibitors for Reinforced Concrete Bridge Decks

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Publisher :
ISBN 13 :
Total Pages : 459 pages
Book Rating : 4.:/5 (669 download)

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Book Synopsis Evaluation of Multiple Corrosion Protection Systems and Corrosion Inhibitors for Reinforced Concrete Bridge Decks by : Lihua Xing

Download or read book Evaluation of Multiple Corrosion Protection Systems and Corrosion Inhibitors for Reinforced Concrete Bridge Decks written by Lihua Xing and published by . This book was released on 2010 with total page 459 pages. Available in PDF, EPUB and Kindle. Book excerpt: The corrosion performance of different corrosion protection systems is evaluated using the mortar-wrapped rapid macrocell test, bench-scale tests (the Southern Exposure, cracked beam, and ASTM G109 tests), and field tests. The systems include conventional steel with three different corrosion inhibitors (DCI-S, Hycrete, and Rheocrete), epoxy-coated reinforcement (ECR) with three different corrosion inhibitors and ECR with a primer coating containing microencapsulated calcium nitrite, multiple-coated reinforcement with a zinc layer underlying an epoxy coating, ECR with zinc chromate pretreatment before application of the epoxy coating to improve adhesion between the epoxy and the underlying steel, ECR with improved adhesion epoxy coatings, and pickled 2205 duplex stainless steel. Conventional steel in concretes with two different water-cement ratios (0.45 and 0.35) is also tested. Of these systems, specimens containing conventional steel or conventional epoxy-coated steel serve as controls. The critical chloride thresholds of conventional steel in concrete with different corrosion inhibitors and zinc-coated reinforcement are determined. The results of the tests are used in an economic analysis of bridge decks containing different corrosion protection systems over a design life of 75 years. The results indicate that a reduced water-cement ratio improves the corrosion resistance of conventional steel in uncracked concrete compared to the same steel in concrete with a higher water-cement ratio. The use of a corrosion inhibitor improves the corrosion resistance of conventional steel in both cracked and uncracked concrete and delays the onset of corrosion in uncracked concrete, but provides only a very limited improvement in the corrosion resistance of epoxy-coated reinforcement due to the high corrosion resistance provided by the epoxy coating itself. Based on results in the field tests, the epoxy-coated bars with a primer containing microencapsulated calcium nitrite show no improvement in the corrosion resistance compared to conventional epoxy-coated reinforcement. Increased adhesion between the epoxy coating and reinforcing steel provides no improvement in the corrosion resistance of epoxy-coated reinforcement. The corrosion losses for multiple-coated reinforcement are comparable with those of conventional epoxy-coated reinforcement in the field tests in uncracked and cracked concrete. Corrosion potential measurements show that the zinc is corroded preferentially, providing protection for the underlying steel. Pickled 2205 stainless steel demonstrates excellent corrosion resistance, and no corrosion activity is observed for the pickled 2205 stainless steel in bridge decks, or in the SE, CB, or field test specimens after four years.

A Comparative Laboratory Study of Metallic Reinforcing Steels for Corrosion Protection of Reinforced Concrete Bridge Structures

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Publisher :
ISBN 13 :
Total Pages : 156 pages
Book Rating : 4.:/5 (14 download)

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Book Synopsis A Comparative Laboratory Study of Metallic Reinforcing Steels for Corrosion Protection of Reinforced Concrete Bridge Structures by : Seung-Kyoung Lee

Download or read book A Comparative Laboratory Study of Metallic Reinforcing Steels for Corrosion Protection of Reinforced Concrete Bridge Structures written by Seung-Kyoung Lee and published by . This book was released on 2018 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents study findings related to corrosion resistance of 12 types of metallic reinforcing steel bars. The accelerated laboratory corrosion testing was performed using eight large-scale concrete slabs that simulated typical reinforced concrete bridge decks for about 18 mo by an accelerated corrosion testing protocol followed by a detailed autopsy of extracted bar samples and acid-soluble chloride concentrations determined at the bar imprints. The weekly corrosion testing protocol consisted of a 3-d wetting cycle in 15 weight percent chloride solution at 77°F and a 4-d drying cycle at 100°F. The best corrosion performance group of reinforcing bars includes epoxy-coated reinforcing steel, dual-coated reinforcing steel, stainless steel–clad reinforcing steel, and duplex solid stainless reinforcing steel with 23 percent chromium. The intermediate corrosion performance group includes duplex solid stainless reinforcing steel with 21 percent chromium, austenitic solid stainless reinforcing steel, another type of stainless steel–clad reinforcing steel, ferritic solid stainless reinforcing steel with 12 percent chromium, high-strength micro-composite reinforcing steel, and hot-dip galvanized reinforcing steel. The poorest corrosion performance group includes black steel and lean duplex solid stainless reinforcing steel with 12 percent chromium.

An Evaluation of the Performance of Epoxy-coated Reinforcing Steel in Concrete Exposure Specimens

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Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (45 download)

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Book Synopsis An Evaluation of the Performance of Epoxy-coated Reinforcing Steel in Concrete Exposure Specimens by :

Download or read book An Evaluation of the Performance of Epoxy-coated Reinforcing Steel in Concrete Exposure Specimens written by and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The application of a mineral admixture or a combination of a mineral admixture with corrosion inhibitor are the methods used for the corrosion protection for reinforced concrete bridges. The results of a 1.5-year study on evaluation of three concretes with fly ash, slag cement (SC), and silica fume (SF) and one concrete with silica fume and a corrosion inhibitor (SFD) are presented. The specimens were built to simulate four exposure conditions typical for concrete bridges located in the coastal region or inland where deicing salts are used. The exposure conditions were horizontal, vertical, tidal, and immersed zones. The specimens were kept inside the laboratory and were exposed to weekly ponding cycles of 6% sodium chloride solution by weight. In addition, cover depth measurements from 21 bridge decks and chloride data from 3 bridge decks were used, together with laboratory data, in modeling the service lives of investigated corrosion protection methods. The methods used to assess the condition of the specimens included chloride concentration measurements, corrosion potentials, and corrosion rates (3LP). Additionally, visual observations were performed for identification of rust stains and cracking on concrete surfaces. The results of chloride testing indicate that the amount of chlorides present at the bar level is more than sufficient to initiate corrosion. Chloride and rapid permeability data demonstrate that for low permeable (LP) concretes there appears to be significant difference both in a rate of chloride ingress and in the diffusion coefficients in comparison to the controls. Corrosion potentials agree with corrosion rates and suggest the possibility of an active corrosion process development on control specimens during indoor exposure. The structural cracks that were observed in some specimens appeared to have no influence on the corrosion development on the bars in the vicinity of the these cracks. It was concluded that the silicone and duct tape protection was adequate. The cracking, other than structural, appeared to be related to the reinforcing steel corrosion, except the cracks in the horizontal zone of the specimen with slag cement which were probably caused by the subsidence cracking. The least number of cracks was observed on the SF and SFD specimens. Modeling the time as a function of probability of the end of functional service life (EFSL) was presented. It has been shown that the distributions of surface concentrations of chloride ions (C0) and diffusion constants (Dc) are key elements in the model. Model predictions show that the LP concretes provide much better level of protection against moisture and chlorides than the A4 concrete alone. Application of a corrosion inhibitor causes an elevation of the chloride threshold resulting in an additional increase in time to EFSL. Recommendations are to continue monitoring until cracking has occurred in all specimens to a greater extent to better estimate the service lives of LP concretes than is presently known in the construction of concrete bridge components in Virginia. The specimens with LP concretes and one control (continuous reinforcement in the legs) should be taken to the Hampton Road North 1 Tunnel Island and placed in the brackish water to a depth of the immersed zone at low tide for further exposure to chloride. The other control (non-continuous reinforcement in the legs) should remain in an outdoor exposure in Southwest Virginia like the Civil Engineering Materials Research Laboratory in Blacksburg, Virginia. Also more field studies are needed to better estimate distributions of surface chloride concentration and diffusion coefficient of Virginia bridge decks, and to confirm predicted times to EFSL for LP concretes.

Corrosion of Reinforcing Steel in Concrete

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Publisher : ASTM International
ISBN 13 : 9780803103160
Total Pages : 216 pages
Book Rating : 4.1/5 (31 download)

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Book Synopsis Corrosion of Reinforcing Steel in Concrete by : J. Tonini

Download or read book Corrosion of Reinforcing Steel in Concrete written by J. Tonini and published by ASTM International. This book was released on 1980 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Galvanized Steel Reinforcement in Concrete

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

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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

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

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

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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.