Coupling effect of corrosion damage on chloride ions diffusion in cement based materials

Chloride penetration could lead to the rebar corrosion and cause the durability problem in concrete structure under marine environment. It is a coupling process between chloride penetrating and corrosion damage evolving in concrete. This paper proposed an analysis method to deal with this coupling problem. The corrosion damage degree was considered as an internal variable in coefficients of chloride diffusion. Additionally, the interfacial boundary displacement values varied with chloride concentration and service time of concrete structure. This iterative computing algorithm was tackled as user subroutine packaged into software ABAQUS. The numerical examples were given to confirm the reliability of the developed model. The results show that corrosion expanded damage accelerates chloride ions diffusion and vice versa.

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Molecular Dynamics Study of the Interaction of C-S-H and Chloride Ions

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.711.1061 ◽

2016 ◽

Vol 711 ◽

pp. 1061-1068

Author(s):

Yang Zhou ◽

Guo Dong Xu

Keyword(s):

Molecular Dynamics ◽

Calcium Silicate Hydrate ◽

Chloride Concentration ◽

Sorption Isotherms ◽

Hydration Product ◽

Chloride Ions ◽

Dynamics Modeling ◽

Solution Interface ◽

Molecular Dynamics Modeling ◽

Cement Based Materials

Molecular Dynamics was employed to investigate the interaction of calcium silicate hydrate (C-S-H), the primary hydration product of cement based materials, and chloride, causing severe durable problems of concrete. The 11Å tobermorite structure was chosen to describe the C-S-H structure and the CLAYFF force field was used. It is observed in the simulation that there are no bound chlorides at 303K, while a fraction of chlorides appear in the adsorption district of tobermorite/solution interface at 323K indicating the temperature increase can improve chloride sorption capacity of C-S-H. The formation of Ca-Cl cluster is found on the surface of tobermorite, which is assumed to promote the chloride sorption. The experimental results of sorption isotherms of C-S-H in CaCl2 and NaCl aqueous solutions with the same chloride concentration have proved this point. Other researchers have made the same conclusion by means of molecular dynamics modeling, NMR tests or zeta potential experiments.

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Cement-based materials destruction under the action of deicing salts

MATEC Web of Conferences ◽

10.1051/matecconf/201929800053 ◽

2019 ◽

Vol 298 ◽

pp. 00053 ◽

Cited By ~ 1

Author(s):

Ekaterina Potapova ◽

Ivan Korchunov

Keyword(s):

Aqueous Solution ◽

Pore Solution ◽

Colorimetric Method ◽

Chloride Ions ◽

Cement Matrix ◽

Chloride Solutions ◽

Deicing Salts ◽

Cement Based Materials ◽

Destructive Processes

The results of chloride ions with aqueous solution penetrating into the cement structure were determined with the colorimetric method. Some tendencies of chloride solutions migration in different conditions were established. The article suggests the possible ways of the prevention of destructive processes occur during the excessive pore solution saturation in cement matrix with chloride ions.

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Evaluation of the Corrosion Rate for Acidic Bottom Plates of an Aboveground Oil Tank by the AE Method

Volume 5: High Pressure Technology; Nondestructive Evaluation Division; Student Paper Competition ◽

10.1115/pvp2008-61517 ◽

2008 ◽

Author(s):

Naoya Kasai ◽

So Soon Park ◽

Kentaro Utatsu ◽

Kazuyoshi Sekine ◽

Shigeo Kitsukawa ◽

...

Keyword(s):

Corrosion Rate ◽

Corrosion Behavior ◽

Polarization Resistance ◽

Corrosion Damage ◽

Strong Acid ◽

Chloride Ions ◽

Impedance Method ◽

Test Pieces ◽

Oil Storage ◽

Ae Signals

An AE method is an effective technique that can inspect corrosion damage of tank bottom plates to prevent leakage accidents of oil storage tanks. However, a correlation between AE signals and the corrosion behavior for bottom plates is not fully clarified. In this study, the authors considered that the corrosion regions in bottom plates become a strong acid environment by chloride ions as shown our previous work. The correlation between the AE signals and the corrosion behavior with a potentiostat for test pieces was examined in the environment. The polarization resistance was measured with an AC impedance method using a frequency response analyzer. It was clear that the polarization resistance indicated the corrosion rate for a test pieces in the experiments. While measuring the AE signals, the corrosion rate was monitored with a test piece. As a result, the AE signal showed the good correlation with the corrosion rates of the test pieces.

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Experiment Study on the Durability of Dry-Mixing Self-Compacting Concrete

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.250-253.493 ◽

2011 ◽

Vol 250-253 ◽

pp. 493-496 ◽

Cited By ~ 1

Author(s):

Lan Zong ◽

Shi Ping Zhang ◽

Pei Xin Liang

Keyword(s):

Pore Structure ◽

Frost Resistance ◽

Chloride Ions ◽

Experiment Study ◽

Self Compacting Concrete ◽

Freeze Thaw ◽

Coarse Aggregates ◽

Carbonation Resistance ◽

Dry Mixing ◽

Chloride Ions Diffusion

Durability of dry-mixing self-compacting concrete was evaluated through carbonation testing, freeze-thaw testing and chloride ions diffusion testing. The results indicate that carbonation resistance, frost resistance and chloride ions diffusion of durability of dry-mixing self-compacting concrete are excellent, compared with normally vibrated concrete (NVC). Durability of dry-mixing self-compacting concrete shows a better pore structure. Furthermore, the more the content of coarse aggregates is, the poorer the pore structure becomes.

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Epoxy Resin/Recycled Sand Mortars’ Resistance to Chloride Ions Diffusion

CONCREEP 10 ◽

10.1061/9780784479346.100 ◽

2015 ◽

Author(s):

Amal Bourguiba ◽

Elhem Ghorble ◽

Wadia Dhaoui

Keyword(s):

Epoxy Resin ◽

Chloride Ions ◽

Chloride Ions Diffusion

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New equation for description of chloride ions diffusion in concrete under shallow immersion condition

Materials Research Innovations ◽

10.1179/1432891714z.000000000413 ◽

2014 ◽

Vol 18 (sup2) ◽

pp. S2-265-S2-269 ◽

Cited By ~ 2

Author(s):

J. Liu ◽

F. Xing ◽

B. Q. Dong ◽

H. Y. Ma ◽

D. Pan

Keyword(s):

Chloride Ions ◽

Chloride Ions Diffusion ◽

Immersion Condition ◽

New Equation

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Durability Investigation of Carbon Fiber Reinforced Concrete under Salt-Freeze Coupling Effect

Materials ◽

10.3390/ma14226856 ◽

2021 ◽

Vol 14 (22) ◽

pp. 6856

Author(s):

Yongcheng Ji ◽

Wenchao Liu ◽

Yanmin Jia ◽

Wei Li

Keyword(s):

Reinforced Concrete ◽

Carbon Fiber ◽

Coupling Effect ◽

Chloride Ion ◽

Chloride Ions ◽

Fiber Reinforced Concrete ◽

Ion Concentration ◽

Fiber Reinforced ◽

Ion Distribution ◽

Carbon Fiber Reinforced

In order to study the durability behavior of CFRP (carbon fiber reinforced polymer) reinforced concrete, three category specimens (plain, partially reinforced, and fully reinforced) were selected to investigate its performance variation concerning chlorine salt and salt-freeze coupled environment, which included the microscopic examination, the distribution of chloride ion concentration, and the compressive properties. By observing the microscopic of the specimens, the surface and cross-section corrosion deterioration was examined with increasing exposure time, and the physical behavior of CFRP and core concrete were discussed. The chloride ion diffusion test exerted that the chloride ion concentration in plain specimens is at least 200 times higher than that of fully reinforced specimens. Therefore, the effectiveness of CFRP reinforcement will be proved to effectively hinder the penetration of chloride ions into the core section. The formula of the time-dependent effect of concrete diffusivity with salt-freeze coupling effect was presented and its accuracy verified. A time-varying finite element model of chloride ion distribution was established by using ABAQUS software. It can be seen from the axial compression test that the strength loss rate of three categories of specimens was varied when subjected to the corrosion environment. Therefore, it is proved that CFRP reinforcement can effectively reduce the deterioration of the specimen’s mechanical properties caused by the exposure environment. The research results can provide technical reference for applying the CFRP strengthened concrete in a severe salt-freeze environment.

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Diffusion Behavior of Chloride Ions in Concrete Box Girder under the Influence of Load and Carbonation

Materials ◽

10.3390/ma13092117 ◽

2020 ◽

Vol 13 (9) ◽

pp. 2117

Author(s):

Yinglong Liu ◽

Pengzhen Lin ◽

Junjun Ma

Keyword(s):

Coupling Effect ◽

Chloride Concentration ◽

Chloride Ion ◽

Chloride Ions ◽

Ion Concentration ◽

Scale Model ◽

Test Results ◽

Box Girder ◽

Concrete Box Girder ◽

The Difference

In order to study the durability degradation characteristics of concrete box girder under load and carbonation and chloride ion erosion, a scale model of concrete box girder was made for experimental research. According to the test results, the diffusion characteristics of chloride ions in the concrete box girder under the coupling effect of load and carbon dioxide were analyzed. By revising the calculation formula of the existing chloride ion concentration considering multiple factors, a calculation model of chloride ion concentration considering the influence of carbonation was proposed, and the test results were verified. The results show that the chloride concentration of the box girder on the same cross section is non-uniformly distributed due to the shear lag effect and the spatial structure. After considering the effect of carbonation, the difference rate of the improved model proposed in this paper is generally within 10%. Compared with the original model, the difference rate is reduced by a maximum of 19%.

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