The Effect of Surface Hydrophobation Silane Treatment on Chloride Ion Penetration Resistance for Concrete Structures in Marine Environments

Effect of concrete surface hydropobation treatment against chloride penetration have been studied by in-site exposure test. The results show that the silane impregnated layer can prevent the chlorides penetration into the concrete substrate effectively, reduce the apparent chloride ion diffusion coefficient and surface chloride concentration, and improve the service life of concrete structure; and the depth of concrete convection zone can reduce due to silane impregnated layer for concrete in the marine environment of wetting and drying area.

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Experimental Study on the Corrosion Law of Chloride in Concrete under Artificial Climate

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.405-408.2520 ◽

2013 ◽

Vol 405-408 ◽

pp. 2520-2523

Author(s):

Yi Wan ◽

Zhi Wu Yu ◽

Peng Liu ◽

Yu Yan Sun

Keyword(s):

Experimental Study ◽

Diffusion Coefficient ◽

Diffusion Coefficients ◽

Convection Zone ◽

Concrete Strength ◽

Chloride Ion ◽

Concrete Surface ◽

Ion Diffusion ◽

Different Depths ◽

Chloride Ion Diffusion

Corrosion experimental were conducted in order to study concrete samples of two strength grades during different erosion period under the condition of designed artificial chloride erosion.Through drilling powder of concrete surface at various depths,chloride ions’concentration at different depths of corroded samples were determinated,and the diffusion coefficients of chloride ion after 90,180,240 days of corrosion were calculated on the basis of Fick’s second law.It turns out that obvious convection zone exitsin corroded concrete,and the thickness of convection zone increases with the erosing time and the reduction of concrete strength grade.In addtion,fitted datas of chloride ion diffusion coefficient increases with the reduction of concrete strength grade.

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EFFECT OF CRUMB RUBBER ON CONCRETE STRENGTH AND CHLORIDE ION PENETRATION RESISTANCE

Jurnal Teknologi ◽

10.11113/jt.v77.7004 ◽

2015 ◽

Vol 77 (32) ◽

Cited By ~ 1

Author(s):

Nurazuwa Md Noor ◽

H. Hamada ◽

Y. Sagawa ◽

D. Yamamoto

Keyword(s):

Structural Strength ◽

Salt Water ◽

Chloride Ion ◽

Crumb Rubber ◽

Rubberized Concrete ◽

Migration Test ◽

Ion Diffusion ◽

Steady State Condition ◽

Chloride Ion Penetration ◽

Chloride Ion Diffusion

This paper present the effect of crumb rubber on its ability to produce concrete with structural strength when it was used directly from the plant without any treatment process. Crumb rubber was added as fine aggregates at 0%, 10%, 15% and 20% of sand volume meanwhile silica fume was added at 10% by cement weight. Three main series of concrete namely rubberized concrete with water-to-cement ratio of 50% and 35% was design and development of compressive strength was observed from day 7 until 91 days. Also, effectiveness of crumb rubber under flexural strength and splitting tensile strength was studied at 28 days curing age. Effect of crumb rubber on durability performance was done on chloride ion penetration resistance performance by migration test and by immersion in salt water. Chloride ion diffusion in rubberized concrete by migration test was carried out under steady state condition using effective diffusion coefficient, De meanwhile, immersion test in salt water was conducted under non-steady state condition using apparent diffusion coefficient, Da. Results showed that compressive strength was decrease with the increasing of crumb rubber in the mixture. Even though the strength were reducing with the inclusion of crumb rubber, the reduction were less than 50% and it achieved acceptable structural strength. Chloride transport characteristics were improved by increasing amount of CR and rubberized concrete with w/c = 0.35 gave better resistance against chloride ion compared to w/c = 0.50 with more than 50% difference. Silica fume provide slightly strength increment compared to normal rubberized concrete and the same behavior was observed during chloride ion diffusion test.

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Research on Chloride Diffusion Model of PC with Chloride Attack in Marine Atmosphere Zone

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.711.481 ◽

2014 ◽

Vol 711 ◽

pp. 481-484

Author(s):

Yu Chen ◽

Jie Xu ◽

Rong Gui Liu ◽

Su Bi Chen ◽

Yuan Gao

Keyword(s):

Prestressed Concrete ◽

Concentration Distribution ◽

Concrete Structures ◽

Chloride Concentration ◽

Chloride Ion ◽

Ion Concentration ◽

Chloride Diffusion ◽

Marine Atmosphere ◽

Ion Diffusion ◽

Chloride Ion Diffusion

Based on the existing studies about chloride ion erosion in prestressed concrete structures, this paper intends to discuss the effects of the stress level and environment factors (including temperature and humidity, etc.) on chloride ion diffusion under marine atmosphere zone. The investigation from pre-stressed concrete crossbeams which service for 39 years in Lianyungang Port shows the chloride ion concentration distribution and chloride ion diffusion. According to the chloride ion concentration distribution, it finds that chloride ion concentration values in pre-concrete structures is Cmax,1> Cmax,2. In addition, the free chloride concentration distribution values go down smoothly after the second peak. Therefore, the result shows that the improved model can be used in marine atmosphere zone.

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Evaluation of Chloride-Ion Diffusion Characteristics of Wave Power Marine Concrete Structures

Materials ◽

10.3390/ma14195675 ◽

2021 ◽

Vol 14 (19) ◽

pp. 5675

Author(s):

Changhyuck Lim ◽

Gyuyong Kim ◽

Gyeongtae Kim ◽

Bokyeong Lee ◽

Youngduck Kim ◽

...

Keyword(s):

Diffusion Coefficient ◽

Atmospheric Pressure ◽

Concrete Structures ◽

Chloride Ion ◽

Wave Power ◽

Ion Diffusion ◽

Chloride Ion Penetration ◽

Chloride Attack ◽

Marine Concrete ◽

Chloride Ion Diffusion

Wave power marine concrete structures generate electrical energy using waves. They are exposed to a multi-deterioration environment because of air and hydrostatic pressure and chloride attack. In this study, the effect of air pressure repeatedly generated by water level change of wave power marine concrete structures on the chloride-ion diffusion of marine concrete was analyzed. The chloride-ion diffusion of wave power marine concrete structures was evaluated. The results show that the air chamber and bypass room, which were subjected to repetitive air pressures caused by water level changes, showed a higher water-soluble chloride-ion content compared to the generator room and docking facility, which were subjected to atmospheric pressure. Field exposure tests and indoor chloride attack tests were performed using fabricated specimens to analyze the effect of pressure on chloride-ion penetration. It was confirmed that Portland blast furnace slag had a greater inhibitory effect on chloride-ion penetration than ordinary Portland cement. The concrete specimens subjected to pressure showed increased capillary pores and micro-cracks. We devised an equation for calculating the diffusion coefficient based on measured data and estimating the diffusion coefficient for the location receiving repeated air pressure by using the diffusion coefficient of the location receiving general atmospheric pressure.

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Experimental Study on Chloride Ion Diffusion in Concrete under Uniaxial and Biaxial Sustained Stress

Materials ◽

10.3390/ma13245717 ◽

2020 ◽

Vol 13 (24) ◽

pp. 5717

Author(s):

Xiaokang Cheng ◽

Jianxin Peng ◽

C.S. Cai ◽

Jianren Zhang

Keyword(s):

Diffusion Coefficient ◽

Compressive Stress ◽

Stress Level ◽

Chloride Concentration ◽

Chloride Ion ◽

Chloride Ions ◽

Chloride Diffusion ◽

Chloride Diffusion Coefficient ◽

Ion Diffusion ◽

Chloride Ion Diffusion

The existence of axial and lateral compressive stress affect the diffusion of chloride ions in concrete will lead to the performance degradation of concrete structure. This paper experimentally studied the chloride diffusivity properties of uniaxial and biaxial sustained compressive stress under one-dimensional chloride solution erosion. The influence of different sustained compressive stress states on chloride ion diffusivity is evaluated by testing chloride concentration in concrete. The experiment results show that the existence of sustained compressive stress does not always inhibit the diffusion of chloride ions in concrete, and the numerical value of sustained compressive stress level can affect the diffusion law of chloride ions in concrete. It is found that the chloride concentration decreases most when the lateral compressive stress level is close to 0.15 times the compressive strength of concrete. In addition, the sustained compressive stress has a significant effect on chloride ion diffusion of concrete with high water/cement ratio. Then, the chloride diffusion coefficient model under uniaxial and biaxial sustained compressive stress is established based on the apparent chloride diffusion coefficient. Finally, the results demonstrate that the chloride diffusion coefficient model is reasonable and feasible by comparing the experimental data in the opening literature with the calculated values from the developed model.

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The Effect of Superplasticizer on Strength and Chloride Permeability of Concrete Containing GGBFS

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.804.12 ◽

2013 ◽

Vol 804 ◽

pp. 12-16 ◽

Cited By ~ 1

Author(s):

Shi Yi Zhang ◽

Ying Fang Fan ◽

Ning Ning Li

Keyword(s):

Mechanical Property ◽

Compressive Strength ◽

Diffusion Coefficients ◽

Chloride Ion ◽

Ion Diffusion ◽

Chloride Permeability ◽

Additive Content ◽

Chloride Ion Penetration ◽

Chloride Ion Diffusion

The effect of superplasticizer on the mechanical property and chloride permeability of concrete containing GGBFS is investigated in this paper. Compressive and rapid chloride-ion diffusion tests were conducted to determine the axial compressive and chloride-ion diffusion coefficients of GGBFS modified concrete. The tests result indicated that the compressive strength of GGBFS modified concrete with the addition of 2wt. % superplasticizer are further improved at 14 and 28 days. Superplasticizer can significantly enhance the resistance to chloride ion penetration of concrete containing GGBFS with a reasonable additive content at long-term age. The optimum content of superplasticizer is suggested to be 1wt. % to 2wt. % of the cementitous materials.

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A Study on the Evaluation of Probabilistic Durability Life for RC Structures Deteriorated by Chloride Ion

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.348-349.417 ◽

2007 ◽

Vol 348-349 ◽

pp. 417-420

Author(s):

Dong Seok Kim ◽

Han Seung Lee ◽

Seong Min Lee ◽

Xiao Yong Wang

Keyword(s):

Diffusion Coefficient ◽

Concrete Structures ◽

Prediction Method ◽

Chloride Ion ◽

Ion Diffusion ◽

Rc Structures ◽

Equivalent Age ◽

Chloride Ion Penetration ◽

Reliability Assessments ◽

Chloride Ion Diffusion

Chloride attacks concrete structures becoming a primary factor that deteriorates the durability of concrete structures. For this reason, research has been conducted on chloride ion penetration and diffusion. This research produced an accurate durability life prediction through reliability assessments and proposes a prediction method for the chloride ion diffusion coefficient of a concrete applied assessment program for reliability. As a result, test materials were fabricated using different admixtures and chloride ion diffusion coefficient was calculated by applying an RCPT test at each equivalent age. Based on these results, reliability prediction formulas were indicated through the reliability analysis for a durability life design using a Montecarlo method. In addition, propriety was verified through comparisons and analysis using the proposed formula with the investigated data for chloride ion diffusion.

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Bentonite replacing part of cement concrete for resistance to chloride ion attack

E3S Web of Conferences ◽

10.1051/e3sconf/201913603011 ◽

2019 ◽

Vol 136 ◽

pp. 03011

Author(s):

Jie Luo ◽

Chuanchang Li ◽

Yafei Ma ◽

Lei Wang

Keyword(s):

Compressive Strength ◽

Coarse Aggregate ◽

Chloride Ion ◽

Cementitious Materials ◽

Ion Diffusion ◽

Natural Pozzolan ◽

Cement Production ◽

Chloride Ion Penetration ◽

Chloride Migration ◽

Chloride Ion Diffusion

Bentonite is known as a kind of natural pozzolan that can improve the mechanical properties of cementitious materials and reduce the overall CO2 output of cement production. This study is designed to evaluate the feasibility of using bentonite as a substitute for cement in concrete and analyze the effect of bentonite on resisting chloride ion penetration. The concrete was replaced by equal-quality bentonite for 0%, 5%, 10%, 15% and 20% cement respectively, and the water-cement ratio, fine and coarse aggregate content remained constant. The results indicated that as the bentonite content increased, the compressive strength of the mixes increased first and then decreased. The sample containing 10% bentonite got a higher compressive strength than the other samples. The rapid chloride migration (RCM) tests showed that the samples containing bentonite had better resistance to chloride ion attack than samples without bentonite against chloride, especially the sample containing 10% bentonite. It can be concluded that the concrete with 10% bentonite can improve the resistance to chloride ion diffusion with high compressive strength.

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