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Evaluation Of Multiple Corrosion Protection Systems And Corrosion Inhibitors For Reinforced Concrete Bridge Decks
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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.
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.
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.
Book Synopsis Evaluation of Multiple Corrosion Protection Systems for Reinforced Concrete Bridge Decks by : Jason Draper (P.E.)
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:
Book Synopsis Performance Evaluation of Various Corrosion Protection Systems of Bridges in Colorado by : Yunping Xi
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.
Book Synopsis Evaluation of Corrosion Protection Methods for Reinforced Concrete Highway Structures by : Jennifer L. Kepler
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%.
Book Synopsis Long-term Performance of Corrosion Inhibitors Used in Repair of Reinforced Concrete Bridge Components by : Moavin Islam
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.
Book Synopsis A Bibliography on the Corrosion and Protection of Steel in Concrete by : E. Escalante
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:
Book Synopsis Evaluation of Select Methods of Corrosion Control, Corrosion Prevention, and Repair in Reinforced Concrete Bridges by : Habib Tabatabai
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:
Book Synopsis Manual on Service Life of Corrosion-damaged Reinforced Concrete Bridge Superstructure Elements by : Ali Akbar Sohanghpurwala
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:
Book Synopsis Evaluation of Two Corrosion Inhibitors Using Two Surface Application Methods for Reinforced Concrete Structures by : Stephen R. Sharp
Download or read book Evaluation of Two Corrosion Inhibitors Using Two Surface Application Methods for Reinforced Concrete Structures written by Stephen R. Sharp and published by . This book was released on 2004 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study investigated the use of penetrating corrosion inhibitors to extend the life of existing reinforced concrete bridge decks. The use of assisted (vacuum/pressure injection) and unassisted (diffusion) treatment methods and two inhibitors were evaluated. The inhibitors were FerroGard 903, from Sika Corp., and TPS-II, from Surtreat International. Testing was performed on exposure slabs with 15 lb/yd3 of NaCl in the top layer and no NaCl in the bottom layer. The slab design was a variation of the specimen design provided in ASTM G109, with each slab containing nine steel reinforcing rods instead of three. The exposure slabs had either a uniform cover over the top pieces of steel or an inclined cover over the steel. TPS-II was also evaluated on the deck of a bridge in Orange County, Virginia. The study found that when applied to the concrete surface, neither inhibitor penetrated the concrete to reach the steel reinforcement. The vacuum/pressure injection method showed promise but requires refinement. In addition, based on macro-cell measurements, a sufficient quantity of inhibitor can be injected into the concrete to reduce the charge passed.
Book Synopsis Performance of Multiple Corrosion Protection Systems for Reinforced Concrete Bridge Decks by : Matthew O'Reilly
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:
Book Synopsis Evaluation of Corrosion Inhibitors for Concrete Bridge Deck Patches and Overlays by : Michael M. Sprinkel
Download or read book Evaluation of Corrosion Inhibitors for Concrete Bridge Deck Patches and Overlays written by Michael M. Sprinkel and published by . This book was released on 2003 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents the results to date of a national pooled fund study initiated in August 1996 to evaluate the long-term performance of bridges and outdoor exposure slabs damaged by chloride-induced corrosion that have concrete containing corrosion inhibiting admixtures and that had topical applications of inhibitors prior to being patched and overlaid. The study includes 156 exposure slabs, 4 bridge decks with overlays, and 1 patched bridge substructure. A total of 136 exposure slabs were constructed to simulate overlay and patch repairs, and 20 full-depth slabs were constructed to simulate new construction. Each repaired slab was constructed with one of four levels of chloride to cause corrosion. The new slabs were ponded to cause corrosion. Previous reports provide details on the construction and initial condition of the exposure slabs and the construction and initial condition of the repaired bridges. The results presented here are based on quarterly nondestructive measurements between September 1997 and June 2001, visual inspections of the exposure slabs, and tensile bond test results and visual inspections of reinforcement removed from the exposure slabs that were patched and overlaid. Overlays cracked and delaminated on exposure slabs that were fabricated with 15 lb/yd3 of chloride ion because of corrosion of the top mat of reinforcement. There was no difference in the performance of overlays constructed with and without inhibitors and topical treatments. Overlays and patches with and without inhibitor treatments placed on and in slabs with 3, 6, and 10 lb/yd3 of chloride are performing satisfactorily. However, results do not show reductions in the tendency for corrosion that can be attributed to the inhibitors. Overlays and patches with and without inhibitor treatments on and in the five bridges indicate mixed results. Corrosion is occurring in the majority of the repairs done with and without inhibitor treatments. The corrosion-inhibiting treatments do not seem to be reducing corrosion in the bridges and, in fact, may be increasing corrosion. It is not obvious that corrosion is occurring in the full-depth slabs constructed with and without inhibitors to represent new construction. The slabs do not show signs of corrosion-induced cracking after 5 years of ponding. Topical applications of inhibitors did not affect the bond strength of the overlays. Overlays containing Rheocrete 222+ and 7 percent silica fume had lower bond strengths. Overlays on base concretes with the higher chloride content had lower bond strengths. In summary, this project does not show any benefit from the use of the corrosion inhibiting admixtures and the topical applications made to the chloride-contaminated concrete surfaces prior to placement of the patches and overlays. Additional years of monitoring of the exposure slabs and bridges may provide useful results.
Book Synopsis Corrosion Protection Performance Evaluation of Low Permeable Concretes in Exposure Specimens by : Jerzy Zemajtis
Download or read book Corrosion Protection Performance Evaluation of Low Permeable Concretes in Exposure Specimens written by Jerzy Zemajtis and published by . This book was released on 1999 with total page 152 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 (CO) 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 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.
Book Synopsis Corrosion of Reinforcement in Concrete by : M Raupach
Download or read book Corrosion of Reinforcement in Concrete written by M Raupach and published by Woodhead Publishing. This book was released on 2014-01-23 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: Given the widespread use of reinforced concrete in infrastructure, understanding the corrosion of this material is of major importance. As a result there has been a wealth of research into catalysts, inhibitors and effective means of monitoring the rate of corrosion. Corrosion of reinforcement in concrete: mechanisms, monitoring, inhibitors and rehabilitation techniques summarises some of the most significant research and its implications.The book begins by reviewing findings from various experiments designed to test the corrosion rate of metals induced by a range of factors. Later chapters discuss techniques for monitoring and testing for corrosion. The book concludes by assessing important methods of prevention, including corrosion inhibitors, protective coatings and electrochemical methods for protection, together with rehabilitation procedures for susceptible structures.Filled with practical examples and written by a distinguished team of international contributors, Corrosion of reinforcement in concrete: mechanisms, monitoring, inhibitors and rehabilitation techniques is an essential reference for civil engineers using reinforced concrete. Summarises research into catalysts, inhibitors and effective means of monitoring the rate of corrosion Concludes by assessing important methods of prevention
Book Synopsis Evaluation of Bridge Deck Cathodic Protection by : Carey L. Younger
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:
Book Synopsis Performance Evaluation of Corrosion Inhibitors and Galvanized Steel in Concrete Exposure Specimens by : Jerzy Zemajtis
Download or read book Performance Evaluation of Corrosion Inhibitors and Galvanized Steel in Concrete Exposure Specimens written by Jerzy Zemajtis and published by . This book was released on 1999 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Corrosion inhibitor admixtures (CIA) and galvanized reinforcing steel (GS) are used for the corrosion protection for reinforced concrete bridges. The results of a 3.5-year evaluation of exposure specimens containing CIA from three different manufacturers and GS 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. The methods used to assess the condition of the specimens included chloride concentration measurements, corrosion potentials, and corrosion rates. 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 indicate no significant difference either in a rate of chloride ingress or in the diffusion coefficients for concretes with and without CIA. Corrosion potentials were the most negative for the Bare Steel (BS) specimen prepared with the Armatec 2000 corrosion inhibitor and generally indicated a 90% probability of active corrosion. Corrosion potentials were similar for the two BS control specimens and the BS specimen prepared with Rheocrete 222 and generally indicated an uncertain probability of corrosion. Corrosion potentials were the least negative for the BS specimen prepared with DCI-S corrosion inhibitor and generally indicated a 90% probability of no corrosion. Rate of corrosion measurements were the highest for the BS control specimens and the one prepared with A2000 and the most recent data suggest corrosion damage in 2 to 10 years. Although early rate of corrosion measurements were higher or about the same as for BS control specimens, recent measurements were slightly lower for the specimen prepared with Rheocrete 222 and suggest corrosion damage in 10 to 15 years. Rate of corrosion measurements were consistently the lowest for the BS specimens prepared with DCI-S and indicate corrosion damage is expected in 10 to 15 years. The corrosion potential and rate of corrosion data indicate that DCI-S is the only CIA evaluated that clearly provides some level of corrosion protection. A direct comparison of the GS specimens to the BS specimens is not possible because the measured potential refers to the zinc oxide and not to the steel. Nevertheless, the potential data agree with the chloride and permeability data, as well as with the visual observations, and indicate the damaging effect of a high concentration of chloride ions on the GS. At low and moderate chloride exposures, however, GS does provide corrosion protection. Recommendations are to continue monitoring until sufficient cracking has occurred in all specimens to provide for making a better estimate of the service lives of CIA and GS used in the construction of concrete bridge components in Virginia. The specimens with CIA and one control (continuous reinforcement in the legs) should be taken to the Hampton Road North Tunnel Island and placed in the brackish water to a depth of the Immersed Zone at low tide for further exposure to chloride. The specimens with GS and 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.
