SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium最新文献

Formation and Stability of Protective Passive Films formed on the New Generation of Stainless Steel Rebar Alloys 新一代不锈钢螺纹钢合金钝化保护膜的形成及稳定性

SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium Pub Date : 2013-03-29 DOI: 10.14359/51685613

B. Bergsma, C. Hansson

引用次数: 2

Economical Tests for Assessing Corrosion Performance of Steel in Concrete 评定钢在混凝土中的腐蚀性能的经济试验

SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium Pub Date : 2013-03-29 DOI: 10.14359/51685619

Ceki Halmen, K. Reinschmidt, D. Trejo

{"title":"Economical Tests for Assessing Corrosion Performance of Steel in Concrete","authors":"Ceki Halmen, K. Reinschmidt, D. Trejo","doi":"10.14359/51685619","DOIUrl":"https://doi.org/10.14359/51685619","url":null,"abstract":"The repair and rehabilitation of corroding infrastructure systems consumes significant resources. It is well documented that significant value is gained by using durable materials that exhibit long-term, repair-free performance. In the US, most state highway agencies (SHAs) are approached by material producers and requests are made to evaluate the material for possible use in the infrastructure system. SHAs have limited resources and are in need of new evaluation methods that are reliable, fast, and cost-effective. This research evaluated four different accelerated test methods for evaluating the corrosion performance of steel in cementitious materials. Results were compared with results from the commonly used standard ASTM G 109 test method. The corrosion performance of conventional bars, stainless steel bars, galvanized bars, and epoxy-coated bars were evaluated using concrete and mortar mixtures with different water-cement ratios and containing different amounts of a corrosion inhibitor. The effectiveness, time requirements, complexity, and costs of the new test methods were compared with the ASTM G 109 method. This research found that the Rapid Macro-cell Test (RMT) is relatively simple to perform and provides reasonable results for most products in a reasonable time frame with minimal relative cost.","PeriodicalId":242991,"journal":{"name":"SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127553254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Refined half-cell potential mapping for corrosion detection using inverse modeling 基于反建模的精细半电池电位映射腐蚀检测

SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium Pub Date : 2013-03-29 DOI: 10.14359/51685618

P. Marinier, O. Isgor

{"title":"Refined half-cell potential mapping for corrosion detection using inverse modeling","authors":"P. Marinier, O. Isgor","doi":"10.14359/51685618","DOIUrl":"https://doi.org/10.14359/51685618","url":null,"abstract":"Accurate determination of the locations and sizes of actively corroding areas on embedded steel reinforcement in concrete is rather challenging using the standardized half-cell potential mapping technique. In this research, it is hypothesized that half-cell potentials on the surface of the concrete can be used, beyond their originally intended purpose, to identify the locations and sizes of anodic and cathodic sites on the steel reinforcement by means of inverse modeling algorithms. The problem, simply put, is a boundary identification problem: given the potential measurements on the surface of the concrete, identify the anodic and cathodic boundaries on the surface of the reinforcement. To this end, a conjugate-gradient based inverse modeling algorithm is developed to assimilate standard half-cell potential measurements on the concrete surface and to calculate the potential distribution on the surface of the reinforcement. The performance of the inverse model is demonstrated with various configurations of corroding systems with single and multiple anodes using identical twin numerical experiments. The results show that the developed inverse modeling algorithm is robust and can be used as a starting point to investigate more practical cases for which the number of observation points on the surface of the concrete is limited.","PeriodicalId":242991,"journal":{"name":"SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128699658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Effects of Anti-Icing Agents on the Durability of Concrete 防冰剂对混凝土耐久性的影响

SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium Pub Date : 2013-03-29 DOI: 10.14359/51685615

M. Cremasco, C. Hansson

{"title":"Effects of Anti-Icing Agents on the Durability of Concrete","authors":"M. Cremasco, C. Hansson","doi":"10.14359/51685615","DOIUrl":"https://doi.org/10.14359/51685615","url":null,"abstract":"Different anti-icing agents are used in various locations in Ontario to meet the specific climate needs of the area in order to minimize, or help remove, snow and ice build-up. These anti-icing agents are generally applied in liquid form and, due to their low freezing temperatures, are able to stay liquid, thus also allowing them to penetrate concrete structures. It has been shown in previous studies that the cations of some of the solutions can react with the cementitious materials to form precipitates of expansive nature. In this project, concrete exposed to the different solutions has been subjected to freezing and thawing both in laboratory tests and in outdoor exposure and to compression testing. However, the salts prevented freezing at the lowest temperatures tested. Therefore, it has been observed that reactions with the calcium and magnesium chlorides can have a positive effect at early ages but a potentially detrimental effect over the long term. The penetration of salt into the dry concrete was determined to be very fast and resulted in a rapid initial increase in the concrete compressive strength but little subsequent strength gain, whereas the strength of concrete exposed to water continues to increase over a longer period.","PeriodicalId":242991,"journal":{"name":"SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128632808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Corrosion of Welded and Chromated Galvanized Lath Reinforcement in Cement Stucco 水泥灰泥中焊接和铬化镀锌板条钢筋的腐蚀

SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium Pub Date : 2013-03-29 DOI: 10.14359/51685616

M. Hunt, C. Hansson, M. Cremasco, Sangkwang Lee, B. Bergsma

{"title":"Corrosion of Welded and Chromated Galvanized Lath Reinforcement in Cement Stucco","authors":"M. Hunt, C. Hansson, M. Cremasco, Sangkwang Lee, B. Bergsma","doi":"10.14359/51685616","DOIUrl":"https://doi.org/10.14359/51685616","url":null,"abstract":"The purpose of this report is to compare the corrosion resistance of several proprietary combinations of stucco and wire reinforcing mesh (lath) to enhance corrosion protection against chloride environments. The lath is produced by spot welding galvanized steel wire and was tested pre-welding, post-welding and after a post-weld chromate treatment. The effect of the weld joint and the chromating on the initial rapid corrosion, typical of zinc embedded in cement-based materials, was first investigated. Despite the loss of zinc at the welds, there was little difference in corrosion rates of the non-welded and welded specimens. The chromating, however, was found to be highly beneficial in eliminating the initial rapid corrosion. A second set of tests investigated the comparative corrosion behavior of the lath in OPC-based stucco and a commercial calcium-aluminate-based stucco (Stucco A) in chloride solution. The study showed the Stucco A to provide less protection than the OPC stucco. Addition of lime to Stucco A, which is not recommended by the manufacturer, resulted in greater corrosion protection.","PeriodicalId":242991,"journal":{"name":"SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127009557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

When Bad Things Happen to Good [Buildings] 当坏事发生在好事上[建筑]

SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium Pub Date : 2013-03-29 DOI: 10.14359/51685621

D. Freytag, K. Kesner, R. Poston, K. Bondy

引用次数: 2

Numerical Study of Pore Solution Chemistry in Surface Crevices of Carbon Steel Rebar 碳钢螺纹钢表面缝隙孔隙溶液化学的数值研究

SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium Pub Date : 2013-03-29 DOI: 10.14359/51685614

O. Isgor, K. Karadakis, P. Ghods

{"title":"Numerical Study of Pore Solution Chemistry in Surface Crevices of Carbon Steel Rebar","authors":"O. Isgor, K. Karadakis, P. Ghods","doi":"10.14359/51685614","DOIUrl":"https://doi.org/10.14359/51685614","url":null,"abstract":"The variability and uncertainty associated with chloride thresholds can be partly explained by the surface conditions of carbon steel rebar, in particular, by the presence of crevices on the steel surface. It has been suggested in the literature that pore solution in the crevices on the steel surface may be different from that of the bulk pore solution, and this difference may create the necessary conditions for the breakdown of the passive film. To test this hypothesis, a numerical investigation was carried out using a non-linear transient finite element algorithm, which involved the solution of coupled extended Nernst-Planck and Poisson’s equations in a domain that represented typical surface crevices on carbon steel rebar. The numerical simulations showed that the chemistry of the pore solution, in particular pH and Cl-/OH-, within crevices provided more favourable conditions for depassivation than the bulk concrete pore solution. Local acidification and increase in Cl-/OH- within the crevice were observed in all simulations, albeit to different degrees. Simulations supported the hypothesis that the chemical composition of the pore solution within the crevices differs from that of the bulk solution through a process similar to the suggested mechanism of typical crevice corrosion.","PeriodicalId":242991,"journal":{"name":"SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123130525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Preliminary Studies of High-Strength Stainless Prestressing Steels 高强度不锈钢预应力钢的初步研究

SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium Pub Date : 2013-03-29 DOI: 10.14359/51685617

R. Moser, L. Kahn, Preet M. Singh, K. Kurtis

{"title":"Preliminary Studies of High-Strength Stainless Prestressing Steels","authors":"R. Moser, L. Kahn, Preet M. Singh, K. Kurtis","doi":"10.14359/51685617","DOIUrl":"https://doi.org/10.14359/51685617","url":null,"abstract":"This paper presents the preliminary results of a study examining the stress vs. strain behavior, stress relaxation, and corrosion resistance of six candidate high-strength stainless steels (HSSSs) for potential use as corrosion-resistant prestressing reinforcement in concrete structures. Austentic grades 304 and 316; duplex grades 2101, 2205, and 2304; and a precipitation hardened martensitic grade 17-7 were selected for the investigation and cold drawn to diameters of approximately 4 mm (0.16 in). Tensile strengths of 1290 to 1550 MPa (185 to 225 ksi) were achieved in the cold-drawn HSSS wires. 1000-hr stress relaxation of all candidate HSSSs was predicted to be between 6 and 8 % based on the results of short-term relaxation tests conducted at 70% ultimate tensile capacity. Cyclic polarization testing for chloride-induced corrosion resistance determined that in alkaline pore solutions, 2205 and 2304 exhibited low corrosion susceptibility and 304 exhibited moderate corrosion susceptibility at 0.5 M chloride concentrations. When exposed to carbonated pore solutions with 0.5 M chloride, grades 2205 and 2304 exhibited low and moderate corrosion susceptibility, respectively. Duplex grade 2205 exhibited superior corrosion resistance in all cases. Based on these results, optimal HSSSs were identified as duplex grades 2205 and 2304.","PeriodicalId":242991,"journal":{"name":"SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium","volume":"96 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116106301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

"Admixed Chlorides in Concrete: History, Impacts, and Standardization" 混凝土中掺加氯化物:历史、影响和标准化

SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium Pub Date : 2013-03-29 DOI: 10.14359/51685612

D. Trejo, R. Weyers

{"title":"\"Admixed Chlorides in Concrete: History, Impacts, and Standardization\"","authors":"D. Trejo, R. Weyers","doi":"10.14359/51685612","DOIUrl":"https://doi.org/10.14359/51685612","url":null,"abstract":"The presence of chlorides in cementitious materials results in corrosion of the embedded metallic materials. Early construction practices (pre 1960s) relied on admixed calcium chloride to accelerate the early strength gain of concrete. Until the 1950s, few publications focused on the effects of chlorides in concrete on corrosion and the use of chlorides was well established. However, in the 1960s significant publications reported on the effects of chlorides on the corrosion of prestressed wires and strands – these publications were the result of several failures of prestressed systems. Later, significant research was performed on the corrosion of steels in cementitious materials―a significant portion of this work attributable to the researchers being recognized in this symposium: Brian Hope and Morris Schupack. Their considerable efforts led to new knowledge regarding corrosion durability of reinforced and prestressed systems. Recently, ACI Committees 201 and 222 standardized limits on allowable admixed chlorides in the constituent materials. However, more standardization is needed―ACI Committees 318 and 349 report different admixed chloride limit requirements than Committees 201 and 222. This paper provides an overview of past research, analyzes the effects of chlorides on service life and economy and provides data from a research project. Using this information, the authors propose a standardized limit for chlorides in concrete.","PeriodicalId":242991,"journal":{"name":"SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium","volume":"126 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128024484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Passive Sensors for Detecting Corrosion in Concrete Structures 用于检测混凝土结构腐蚀的被动传感器

SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium Pub Date : 2012-12-01 DOI: 10.14359/51685620

Ali E. Abu Yosef, P. Pasupathy, S. Wood, D. Neikirk

引用次数: 0

SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope &amp; Schupack Corrosion Symposium最新文献

SP-291: Corrosion of Reinforcing Steel in Concrete - Future Direction: Proceedings-Hope & Schupack Corrosion Symposium最新文献