Evaluation of Corrosion Protection Systems and Testing Methods for Conventional Reinforcing Steel
Author | : Bin Ge |
Publisher | : |
Total Pages | : 213 |
Release | : 2004 |
Genre | : Corrosion resistant materials |
ISBN | : |
Download Evaluation Of Corrosion Protection Systems And Testing Methods For Conventional Reinforcing Steel full books in PDF, epub, and Kindle. Read online free Evaluation Of Corrosion Protection Systems And Testing Methods For Conventional Reinforcing Steel ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Author | : Bin Ge |
Publisher | : |
Total Pages | : 213 |
Release | : 2004 |
Genre | : Corrosion resistant materials |
ISBN | : |
Author | : Javier Balma |
Publisher | : |
Total Pages | : 1034 |
Release | : 2005 |
Genre | : Reinforced concrete |
ISBN | : |
Author | : Matthew O'Reilly |
Publisher | : |
Total Pages | : 522 |
Release | : 2011 |
Genre | : Concrete bridges |
ISBN | : |
"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.
Author | : Lihua Xing |
Publisher | : |
Total Pages | : 459 |
Release | : 2010 |
Genre | : Concrete bridges |
ISBN | : |
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.
Author | : Lien Gong |
Publisher | : |
Total Pages | : 138 |
Release | : 2004 |
Genre | : Chromium alloys |
ISBN | : |
The corrosion performance of MMFX and conventional reinforcing steels is compared based on macrocell and bench-scale tests. The conventional steel includes epoxy-coated and uncoated bars. Macrocell tests are conducted on bare bars and bars symmetrically embedded in a mortar cylinder. Specimens are exposed to a simulated concrete pore solution with a 1.6 or 6.4 molal ion concentration of sodium chloride. Bench-scale tests include the Southern Exposure and cracked beam tests. A 15% (6.04 m ion) NaCl solution is ponded on the top of both the Southern Exposure and cracked beam specimens. Mechanical properties are compared with the requirements of ASTM A 615. The uniformity and consistency in chemical composition is evaluated using a scanning electron microscope and an energy dispersive spectrometer. The microstructure of corrosion products is analyzed using a scanning electron microscope. The results indicate that MMFX steel exhibits better corrosion resistance than conventional uncoated steel, but lower corrosion resistance than epoxy-coated bars. In both the macrocell and bench-scale tests, MMFX steel exhibits a macrocell corrosion rate between one-third and two-thirds that of uncoated conventional reinforcing bars, while epoxy-coated reinforcement with the coating penetrated corrodes at a rate between 5% and 25% that of conventional steel. MMFX reinforcing steel is not recommended as a replacement for epoxy-coated reinforcement unless it is used in conjunction with a supplementary corrosion protection system.
Author | : fib Fédération internationale du béton |
Publisher | : fib Fédération internationale du béton |
Total Pages | : 123 |
Release | : 2009-01-01 |
Genre | : Technology & Engineering |
ISBN | : 2883940894 |
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.
Author | : FIB – International Federation for Structural Concrete |
Publisher | : FIB - International Federation for Structural Concrete |
Total Pages | : 52 |
Release | : 1996-09-01 |
Genre | : Technology & Engineering |
ISBN | : 1874266263 |
Author | : J. Mietz |
Publisher | : CRC Press |
Total Pages | : 226 |
Release | : 2020-08-13 |
Genre | : Science |
ISBN | : 1000122433 |
This book compiles the full papers presented in the successful session "Corrosion of Steel in Concrete" at EUROCORR '97. It highlights the areas of technical development in this field, including monitoring of steel reinforcement corrosion, prevention of corrosion and electrochemical repair methods.