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Influence of steel corrosion on axial and eccentric compression behavior of coral aggregate concrete column

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Frontiers of Structural and Civil Engineering 2021年第6期15卷 1415-1425页

作者： Bo DA Yan CHEN Hongfa YU Haiyan MA Bo YU Da CHEN Xiao CHEN Zhangyu WU Jianbo GUO State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Key Laboratory of Coastal Disaster and Defence of Ministry of Education Hohai UniversityNanjing 210098China Guangxi Key Laboratory of Disaster Prevention and Engineering Safety Guangxi UniversityNanning 530004China Department of Civil and Airport Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

To study the behavior of coral aggregate concrete(CAC)column under axial and eccentric compression,the compression behavior of CAC column with different types of steel and initial eccentricity(ei)were tested,and the deformation behavior and ultimate bearing capacity(Nu)were *** results showed that as the ei increases,the Nu of CAC column decreases ***,the steel corrosion in CAC column is severe,which reduces the steel section and steel strength,and decreases the Nu of CAC *** durability of CAC structures can be improved by using new organic coated *** the influence of steel corrosion and interfacial bond deterioration,the calculation models of Nu under axial and eccentric compression were presented.

关键词： coral aggregate concrete column axial compression eccentric compression steel corrosion calculation model

Probabilistic Lifetime Assessment of Marine Reinforced Concrete with steel corrosion and Cover Cracking

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China Ocean Engineering 2011年第2期25卷 305-318页

作者：陆春华金伟良刘荣桂 Institute of Structural Engineering Zhejiang University Department of Civil Engineering Jiangsu University

In order to study the durability behavior of marine reinforced concrete structure suffering from chloride attack, the structural service life is assumed to be divided into three critical stages, which can be characterized by steel corrosion and cover cracking. For each stage, a calculated model used to predict the lifetime is developed. Based on the definition of durability limit state, a probabilistic lifetime model and its time-dependent reliability analytical method are proposed considering the random natures of influencing factors. Then, the probabilistic lifetime prediction models are applied to a bridge pier located in the Hangzhou Bay with Monte Carlo simulation. It is found that the time to corrosion initiation to follows a lognormal distribution, while that the time from corrosion initiation to cover cracking t~ and the time for crack to develop from hairline crack to a limit crack width t2 can be described by Weibull distributions. With the permitted failure probability of 5.0%, it is also observed that the structural durability lifetime mainly depends on the durability life to and that the percentage of participation of the life to to the total service life grows from 61.5% to 83.6% when the cover thickness increases from 40 mm to 80 mm. Therefore, for any part of the marine RC bridge, the lifetime predictions and maintenance efforts should also be directed toward controlling the stage of corrosion initiation induced by chloride ion.

关键词： marine reinforced concrete chloride ingress steel corrosion cover cracking probabilistic lifetime

Effectiveness of inhibitors in increasing chloride threshold value for steel corrosion

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Water Science and Engineering 2013年第3期6卷 354-363页

作者： Jin-xia XU Lin-hua JIANG Wei-lun WANG Li TANG Li CUI College of Mechanics and Materials Hohai University Shenzhen Durability Center for Civil Engineering Shenzhen University

This investigation was aimed at evaluating the effectiveness of corrosion inhibitors in increasing the chloride threshold value for steel corrosion. Three types of corrosion inhibitors, calcium nitrite （Ca（NO2）2）, zinc oxide （ZnO）, and N,N＇-dimethylaminoethanol （DMEA）, which respectively represented the anodic inhibitor, cathodic inhibitor, and mixed inhibitor, were chosen. The experiment was carried out in a saturated calcium hydroxide （Ca（OH）2） solution to simulate the electrolytic environment of concrete. The inhibitors were initially mixed at different levels, and then chloride ions were gradually added into the solution in several steps. The open-circuit potential （Ecorr） and corrosion current density （lcorr） determined by electrochemical impedance spectra （EIS） were used to identify the initiation of active corrosion, thereby determining the chloride threshold value. It was found that although all the inhibitors were effective in decreasing the corrosion rate of steel reinforcement, they had a marginal effect on increasing the chloride threshold value.

关键词： steel corrosion chloride threshold value, electrochemical impedance spectra (EIS),corrosion inhibitor

Parametric study of thermo-hydro-mechanical response of claystone with consideration of steel corrosion

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第3期9卷 67-80页

作者： Y.Jia H.B.Bian G.Duveau J.F.Shao Laboratory of Mechanics of Lille University of Lille Cité Scientifique Villeneuve-d’Ascq 59655 France LEM3 UMR CNRS 7239 Université de Lorraine Ile du Saulcy Metz 57045 France

In this paper,the thermo-hydro-mechanical(THM)response of claystone is studied via a series of parametric studies,considering the evolution of mechanical properties and deformation behavior of corroded *** numerical simulations are performed by using a coupled THM finite element code and two different constitutive models:a visco-elastoplastic model for geological formation and a von Mises type model for steel *** mechanical properties and deformation behavior of corroded steel are described in a conceptual ***,a disposal tunnel supported by a steel liner is studied and a series of parametric studies is defined to demonstrate the corrosion effects of steel liner on the THM response of the *** comparison of different numerical calculations exhibits that the volumetric expansion related to corrosion products has an important impact on the stress and displacement fields in the claystone surrounding the disposal ***,the evolutions of temperature and liquid pressure in the claystone are essentially controlled by its THM properties and independent of the steel corrosion.

关键词： Claystone steel corrosion Thermo-hydro-mechanical(THM) coupling Disposal tunnel corrosion rate Volumetric expansion of corrosion products

corrosion Test of the steel Plate in a WJ-8 Fastener for High Speed Rail

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Journal of Transportation Technologies 2024年第1期14卷 16-30页

作者： Zhiyong Wang Zhiping Zeng Hualiang (Harry) Teng Department of Mechanical Engineering University of Nevada Las Vegas USA School of Civil Engineering Central South University Changsha China Department of Civil and Environmental Engineering and Construction University of Nevada Las Vegas USA

It was found that the steel plate in the composite plate in the WJ-8 fastener used in high speed rail is rusty. The objective of this study is to test the zinc coating of the steel plate. A literature review was conducted to identify the zinc coating techniques, and the companies that can provide different coating service was identified. A salt fog chamber was built that was in compliance with the ANSI B117 code, and the steel plates that were coated by the identified companies were tested using the salt fog chamber. The results indicated that the coating technique that had the best performance in preventing corrosion was the Greenkote plates with passivation. The galvanized option had the roughest coating layer, and it was the most reactive in the salt water solution. This makes it non-ideal for the dynamic rail environment because the increased friction of the plate could damage the supports, especially during extreme temperatures that would cause the rail to expand or contract. Greenkote with Phosphate and ArmorGalv also provided increased corrosion prevention with a smooth, strong finish, but it had more rust on the surface area than the Greenkote with ELU passivation. The ArmorGalv sample had more rust on the surface area than the Greenkote samples. This may not be a weakness in the ArmorGalv process;rather, it likely was the result of this particular sample not having the added protection of a colored coating.

关键词： steel Plate for High Speed Rail Fastening steel corrosion Zinc Coating Salt-Fog Chamber

Inhibitive effect of Xylopia ferruginea extract on the corrosion of mild steel in 1M HCl medium

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International Journal of Minerals,Metallurgy and Materials 2011年第4期18卷 413-418页

作者： Pandian Bothi Raja Afidah Abdul Rahim1 Hasnah Osman1 Khalijah Awang School of Chemical Sciences Universiti Sains Malaysia11800 PenangMalaysia Department of Chemistry Faculty of ScienceUniversity of Malaya50603 Kuala LumpurMalaysia

The alkaloid content of the leaves and stem bark of Xylopia ferruginea plant was isolated and tested for its anticorrosion potential on mild steel corrosion in a hydrochloric acid medium by using electrochemical impedance spectroscopy,potentiodynamic polarization measurement,scanning electron microscopy（SEM）,and Fourier transform infra red（FTIR） *** experimental results reveal the effective anticorrosion potential of the plant *** mixed mode of action exhibited by the plant extract is evidenced from the polarization *** images proof the formation of a protective layer over the mild steel surface,and this is supported by the FTIR *** possible mode of the corrosion inhibition mechanism has also been discussed.

关键词： steel corrosion hydrochloric acid plant extracts corrosion inhibitors polarization

Electrochemical impedance spectroscopy study on the corrosion of the weld zone of 3Cr steel welded joints in CO_2 environments

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International Journal of Minerals,Metallurgy and Materials 2015年第5期22卷 500-508页

作者： Li-ning Xu Jin-yang Zhu Min-xu Lu Lei Zhang Wei Chang corrosion and Protection Center Key Laboratory for Environmental Fracture (MOE) Institute for Advanced Materials and Technology University of Science and Technology Beijing CNOOC Research Institute

The welded joints of 3Cr pipeline steel were fabricated with commercial welding wire using the gas tungsten arc welding （GTAW） technique. Potentiodynamic polarization curves, linear polarization resistance （LPR）, electrochemical impedance spectroscopy （EIS）, scan- ning electron microscopy （SEM）, and energy-dispersive spectrometry （EDS） were used to investigate the corrosion resistance and the growth of a corrosion film on the weld zone （WZ）. The changes in electrochemical characteristics of the film were obtained through fitting of the EIS data. The results showed that the average corrosion rate of the WZ in CO2 environments first increased, then fluctuated, and finally de- creased gradually. The formation of the film on the WZ was divided into three stages： dynamic adsorption, incomplete-coverage layer forma- tion, and integral layer formation.

关键词： petroleum pipelines steel corrosion welded joints carbon dioxide electrochemical impedance spectroscopy

Influence of mill scale and rust layer on the corrosion resistance of low-alloy steel in simulated concrete pore solution

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International Journal of Minerals,Metallurgy and Materials 2017年第1期24卷 64-74页

作者： Jin-jie Shi Jing Ming Jiangsu Key Laboratory of Construction Materials School of Materials Science and EngineeringSoutheast UniversityNanjing 211189China

Electrochemical impedance spectroscopy, cyclic potentiodynamic polarization measurements, and scanning electron microscopy in conjunction with energy-dispersive X-ray spectroscopy were used to investigate the influence of mill scale and rust layer on the passivation capability and chloride-induced corrosion behaviors of conventional low-carbon（LC） steel and low-alloy（LA） steel in simulated concrete pore solution. The results show that mill scale exerts different influences on the corrosion resistance of both steels at various electrochemical stages. We propose that the high long-term corrosion resistance of LA steel is mainly achieved through the synergistic effect of a gradually formed compact, adherent and well-distributed Cr-enriched inner rust layer and the physical barrier protection effect of mill scale.

关键词： steel reinforced concrete low alloy steel low carbon steel steel corrosion corrosion resistance

Environmental boundary and formation mechanism of different types of H2S corrosion products on pipeline steel

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International Journal of Minerals,Metallurgy and Materials 2017年第4期24卷 401-409页

作者： Lei Zhang Hui-xin Li Feng-xian Shi Jian-wei Yang Li-hua Hu Min-xu Lu Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing 100083 China Aircraft Engine Corporation of China Shanghai Commercial Aircraft Engine Manufacturing Co. Ltd. Shanghai 201306 China Shougang Research Institute of Technology Beijing 100043 China China National Offshore Oil Corporation Research Institute Beijing 100027 China

To establish an adequate thermodynamic model for the mechanism of formation of hydrogen sulfide (H2S) corrosion products, theoretical and experimental studies were combined in this work. The corrosion products of API X60 pipeline steel formed under different H2S corrosion conditions were analyzed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction. A thermodynamic model was developed to clarify the environmental boundaries for the formation and transformation of different products. Presumably, a dividing line with a negative slope existed between mackinawite and pyrrhotite. Using experimental data presented in this study combined with previously published results, we validated the model to predict the formation of mackinawite and pyrrhotite on the basis of the laws of thermodynamics. The established relationship is expected to support the investigation of the H2S corrosion mechanism in the oil and gas industry. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg.

关键词： Energy dispersive spectroscopy Forecasting Gas industry Iron ores Pipelines Scanning electron microscopy steel corrosion steel pipe Thermodynamic properties Thermodynamics X ray diffraction X ray spectroscopy