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 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 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 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 Evaluation of Bridge Deck Cathodic Protection written by Carey L. Younger and published by . This book was released on 1994 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Galvanic Cathodic Protection for Reinforced Concrete Bridge Decks written by David Whiting and published by Transportation Research Board National Research. This book was released on 1981 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Select Methods of Corrosion Control Corrosion Prevention and Repair in Reinforced Concrete Bridges written by Habib Tabatabai and published by . This book was released on 2009 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Manual on Service Life of Corrosion damaged Reinforced Concrete Bridge Superstructure Elements written by Ali Akbar Sohanghpurwala and published by Transportation Research Board. This book was released on 2006 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Proceedings of the Conference on Cathodic Protection of Reinforced Concrete Bridge Decks San Antonio Texas February 12 13 1985 written by and published by . This book was released on 1985 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt: The conference focused on the major problem facing highway and bridge engineers: deterioration of concrete bridge decks caused by corrosion of the reinforcing steel. The conference was aimed primarily at giving bridge owners and engineers an understanding of cathodic protection as the only means to stop corrosion on bridge decks.
Download or read book Vermont s Experience with Bridge Deck Protective Systems written by RI. Frascoia and published by . This book was released on 1977 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Intrusion of moisture and deicing chemicals into reinforced concrete bridge decks results in premature deterioration of the concrete and corrosion of the reinforcing steel. Vermont's search for an effective waterproofing system which would seal bridge decks and thus prevent intrusion of the moisture and chlorides has resulted in the application and evaluation of 29 different membrane systems since 1971. A number of the protective membranes have been in service for sufficient time to draw conclusions on their effectiveness. The results of followup evaluations show that several systems have provided complete protection to the bridge decks while a number of other materials have prevented chloride intrusion except in areas where deicing chemicals are often trapped due to the ponding effect of curb lines and expansion dams. Such results suggest that the simple and inexpensive materials could be specified for sealing the major portion of a deck surface if a compatible and impervious membrane material is placed over poorly drained areas. Difficulties encountered with the application of sophisticated and expensive membrane systems have resulted in a theory that the search for the most effective waterproofing system should concentrate on uncomplicated and less costly materials which could be applied without difficulty.
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 Extended Evaluation of Selected Bridge Deck Protection Systems written by Mark G. Hagen and published by . This book was released on 1995 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: From 1976-1981 the Minnesota Department of Transportation (Mn/DOT) conducted a research study to evaluate several new types of bridge deck protective systems in an effort to reduce the extent of reinforcing steel corrosion. These systems included membranes with bituminous overlays, modified concrete overlays, and coated rebars. When the study concluded, it was felt that a long term study was needed to provide a better indication of service life. Two decks from each system type which appeared promising were selected for extended testing. This extended study continued the evaluation program through 1990
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.
