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.

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.

Download or read book Evaluation of Multiple Corrosion Protection Systems for Reinforced Concrete Bridge Decks written by Jason Draper (P.E.) and published by . This book was released on 2009 with total page 397 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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.

Download or read book Performance 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 487 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Long term Performance of Corrosion Inhibitors Used in Repair of Reinforced Concrete Bridge Components written by Moavin Islam and published by DIANE Publishing. This book was released on 2003 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary objective of the project was to determine the effectiveness of cathodic protection, electrochemical chloride extraction, and corrosion-inhibitor treatment systems installed during the SHRP effort through the long-term evaluation of 32 field test sites and a number of laboratory concrete slab specimens. The FHWA program required monitoring the long-term performance of corrosion inhibitor treatments on selected components of four bridges that were treated and evaluated under SHRP C-103. Three evaluations over a period of 5 years were conducted on structures located in Minnesota, New York and Pennsylvania, and two evaluations were conducted on a structure in Washington State. An analysis of the results concluded that neither of the corrosion inhibitors evaluated in this study, using the specified repairs and exposed to the specific environments, provided any corrosion-inhibiting benefit. Shrinkage cracking plagued repairs at all test sites except for the Washington site.

Download or read book Technical Alert written by Jack Bennett and published by Strategic Highway Research Program (Shrp). This book was released on 1994 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cathodic protection is accepted as a repair option for steel-reinforced structures that are undergoing corrosion caused by the presence of chlorides. The Strategic Highway Research Program (SHRP) issued a contract on cathodic protection of reinforced concrete bridge elements. The objective of part of that contract was to investigate the feasibility of improved and simplified control criteria. To this end, corrosion rates of steel in a concrete environment were measured relative to many factors, and then, data were used to appraise control criteria. This technical alert presents the results and recommendations based on that part of the work.

Download or read book Evaluation of Corrosion Protection Methods for Reinforced Concrete Highway Structures written by Jennifer L. Kepler and published by . This book was released on 2000 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the 1970s, research projects and field studies have been conducted on different methods for protecting reinforced concrete bridges from corrosion damage. The methods include alternative reinforcement and slab design, barrier methods, electrochemical methods, and corrosion inhibitors. Each method and its underlying principles are described, performance results of laboratory and/or field trials are reviewed, and systems are evaluated based on the results of the trials. Using performance results from the studies and costs obtained from transportation agencies, an economic analysis is used to estimate the cost of each system over a 75-year economic life using discount rates of 2%, 4% and 6%.

Download or read book A Bibliography on the Corrosion and Protection of Steel in Concrete written by E. Escalante and published by . This book was released on 1979 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Corrosion Protection written by Yash Paul Virmani and published by . This book was released on 1998 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recognizing the burden that reinforcing steel corrosion imposes on natural resources, the Federal Highway Administration established Corrosion Protection for Concrete Bridges as one of the high-priority areas (HPAs) in its Structures Research Program. This report summarizes the progress made through research efforts conducted under these programs. The results presented cover (A) corrosion control in new concrete constructions (adequate concrete cover, quality concrete, rebar coatings, corrosion inhibiting admixtures, and corrosion protection of prestressed concrete bridge members) and (B) corrosion control for rehabilitation of existing concrete structures (conventional rehabilitation methods, cathodic protection, and electrochemical removal of chloride).

Download or read book Corrosion of Steel in Concrete written by John P. Broomfield and published by CRC Press. This book was released on 2023-01-31 with total page 305 pages. Available in PDF, EPUB and Kindle. Book excerpt: Corrosion of Steel in Concrete: Understanding, Investigation and Repair is a guide for designing, constructing and maintaining reinforced concrete structures, such as buildings and bridges which are subject to reinforcement corrosion. It presents the basics of theory and practice in steel corrosion in concrete and reviews the latest research and developments, such as progress on measuring the corrosion threshold for chloride-induced corrosion. This third edition compares the currently proliferating major national and international standards and guidance documents. New developments are considered, such as hybrid anodes for electrochemical treatment and the latest research and developments in assessment, such as the use of ground penetrating radar to measure the chloride content of the concrete cover. It overhauls coverage of electrochemical repair and rehabilitation techniques and outlines recent innovations in structural repair and construction and investigates their implications for durability. The book is ideal for practitioners and graduate students in structural engineering and concrete technology.

Download or read book Investigation of Corrosion Protection Systems for Bridge Stay Cables written by Homer Robert Hamilton and published by . This book was released on 1995 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of cable-stayed bridges in medium- and long-span applications in the United States has increased significantly in the past ten years. Of paramount importance with this type of bridge is the protection of the stay cables from corrosive elements. An extensive survey, reported herein, showed a general concern over the adequacy of the corrosion protection of the most widely used current system. In this study, the popular two-barrier system (prestressing strand inside polyethylene sheath injected with portland cement grout) was examined experimentally. The effectiveness of the grout in providing secondary corrosion protection in the event of a cut or break in the external sheathing was a major focus of the experimental work.

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 Application of Cathodic Prevention in a New Concrete Bridge Deck in Virginia written by Gerardo G. Clemeña and published by . This book was released on 2003 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Corrosion of reinforcement in concrete bridges has been a major factor in limiting the service life of many such structures. As part of a concerted effort to identify cost-effective options for eliminating corrosion of reinforcement, the application of cathodic prevention was tried in a recently constructed concrete bridge deck. The incorporation of an impressed-current cathodic prevention system in a new concrete bridge deck while it was being constructed was made possible by the use of titanium mesh ribbon anodes coated with mixed-metal oxide. The anodes were spaced 32 cm (13 in.) apart and transversely across the entire bridge deck to allow for the trouble-free placement of the concrete. The system has been operating for almost 2 years with no extraordinary problems. A comparison of the long-term cost of this option with those of other options, such as the use of corrosion-resistant clad bars or stainless steel bars, indicated that this option is not economically favorable.

Download or read book Performance Evaluation of Various Corrosion Protection Systems of Bridges in Colorado written by Yunping Xi and published by . This book was released on 2004 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Corrosion of reinforced concrete structures has been a significant problem for many state and transportation agencies since the application of deicing salts was introduced. Much research has been conducted to develop corrosion protection systems that can prolong the life span of reinforced concrete structures. The Colorado Department of Transportation (CDOT) has several routine and experimental measures to prevent corrosion of the rebar including epoxy-coated rebar, calcium nitrite admixture, organic corrosion inhibitors, a thick cover of quality concrete, and a waterproofing membrane covered by an asphalt overlay. An extensive literature review was performed to collect information on various corrosion protection systems that have been used in the U.S. and around the world. Current CDOT practices in terms of corrosion protection measures were reviewed. A draft inspection plan for Colorado's bridge structures was proposed.

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 Public Roads written by and published by . This book was released on 1987 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: