• Corrosion Science and Technology
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• 제11권4호
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• pp.112-119
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• 2012

This paper presents the results of a study of the effectiveness of cathodic protection with insoluble ICCP anode in reinforced concrete structures. Experimental tests were carried out on reinforced concrete specimens with 3 different commercial anodes for ICCP system in order to compare the effectiveness of cathodic protection. Results have shown that the kinds of anode for ICCP is irrelevant to the effectiveness of cathodic protection, In case of ICCP, the performance of cathodic protection has no relationship to the kinds of anode especially in concrete specimens with sea water condition. It has been found slightly more effective at Ti-Rod anode in fresh water condition and Ti-Mesh anode in atmospheric condition.

• Journal of Advanced Marine Engineering and Technology
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• 제28권8호
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• pp.1286-1290
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• 2004

This paper describes the anti-corrosion system on underwater structures of ships. Metals and alloys have several positions in the series such as immunity, corrosion and passivity. The iron potential has to change from the corrosion position to the anodic protection or cathodic protection for preventing corrosion by providing corrosion protection system such as ICCP(Impressed Current Cathodic Protection). The purpose of ICCP system is to eliminate the rusting or corrosion, which occurs on metal immersed in water. The system includes a power supply unit, which consists of a transformer, a converter. a controller, etc. This paper presents the protection performance of ICCP under dynamic condition such as velocity. The variation of potential and current density with time and environment factors are also described Finally, the experimental results will be explained and analysed.

• Journal of Advanced Marine Engineering and Technology
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• 제17권1호
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• pp.55-65
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• 1993

Galvanic protection method is one the cathodic protection methods and is mostly used for corrosion prevention of heat exchangers and ship's hull. In this paper, it was investigated that how cathodic potential distribution was varied with according to the bare and painted steel plates in case of galvanic anode protection. The results obtained above were as follows. 1. Cathodic potential distribution of a painted steel plate was smoothed than that of the bare steel plate all over the cathodic surface area. 2. It was shown that polarization potential of the bare steel plate was somewhat shifted to negative potential, on the contrary that of the painted steel plate was somewhat shifted from negative potential to positive potential as time gone by beginning of galvanic anode method. 3. The applied current density in order to maintain constant protection potential(-770mv SCE) in the painted steel plate was less than that of the bare steel plate because of the high resistance polarization of the painted steel plate. 4. It was suggested that required number and life-time of anode for galvanic anode protection could be decided easily with corrosion prevention coefficient obtained by experimental data.

• Journal of Advanced Marine Engineering and Technology
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• 제40권7호
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• pp.599-604
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• 2016

음극방식은 19세기 초에 해수 및 지중 금속의 부식을 억제시키기 위한 기술로 처음 소개되었으며, 1970년대에 철근콘크리트 분야에 음극방식 기술이 적용되기 시작하였다. 1990년대에는 국제적으로 많은 연구 및 기술개발로 인하여 철근 부식방지의 효용성이 널리 증명되었다. 국내에도 최근 철근콘크리트 분야에 음극방식이 소개되어 일부 구조물에 적용되기 시작하고 있으며 점차 그 범위가 확대되고 있다. 음극방식의 특징은 일반 콘크리트구조물의 물리적인 보수 유지와는 달리 전기화학적 원리를 응용한 방식기술이기 때문에 다소의 전문적인 지식이 필요하다. 따라서 본 연구에서는 철근콘크리트의 방식기술, 음극방식의 원리, 설계, 적용 등의 기본적인 이론과 철근콘크리트의 음극방식 기준 및 음극방식을 철근콘크리트구조물에 적용할 때의 기술적인 내용 및 적용사례를 소개한다.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2001년도 춘계학술대회 논문집
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• pp.152-157
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• 2001

This paper was studied on the characteristics of crevice corrosion prevention of SS 400 in marine environment. In NaCl solution, polarization behavior under the crevice corrosion was investigated. And Weight loss rate of SS 400 applied cathodic protection and non cathodic protection was measured according to the NaCl concentration. The main results obtained are as follows : The weight loss rate of Al-alloy galvanic anode was increased as the concentration of NaCl solution increased by 3.5% but the concentration increased over 3.5%, that of Al-alloy galvanic anode become decreased. The protective potential of SS 400 used Al-alloy galvanic anode becomes more cathodic polarization with increasing concentration of NaCl solution. Effects of oxygen on the weight loss rate of Al-alloy sacrificial anode for cathodic protection as the concentration of 3.5% NaCl solution become sensitive than that of 0% NaCl solution.

• Corrosion Science and Technology
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• 제4권2호
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• pp.56-59
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• 2005

In rebar concrete structure, the corrosion of rebar can arise the deterioration of concrete structure and may affect the safety of the whole system. Recently, several methods for corrosion protection have been used and are more important for concrete structure using the sand including chloride ion. Among several protections, electrical cathodic protection has been expected to be one of the most useful methods in corrosion protection for reinforcement of concrete structures. The anode for cathodic protection needs high current density, high corrosion resistance and low overvoltage. To fill up the special qualities, the insoluble anodes were developed and these anodes were coated with metal oxide of $TiO_2$, $ZrO_2$, $RuO_2$, and $IrO_2$. Lifetime of these anodes can be one of the important factors affecting the lifetime of concrete structure in cathodic protection. In this work, several anodes were made by sol-gel method and thermal decomposition method and the lifetime of these anodes was evaluated by NACE international standard test method, TM 0294-94. Also, we did analyze the properties of coated metal oxides.

• Journal of Advanced Marine Engineering and Technology
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• 제21권5호
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• pp.584-590
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• 1997

Harbour marine steel structures, which are served in severe marine environment, should be protected in appropriate method to reduce corrosion problems. Cathodic protection, one of the protection methods in terms of practical and economical point of view is being widely used to marine steel structures mentioned above. Recently it has been reported that the life of Al alloy anode with sacrificial anode for protection of harbour marine steel structures was shortened significantly than the original design life. In this study, the optimum cathodic protection design of harbour marine steel structures was investigated with parameter of sea water pollution degree.

• Corrosion Science and Technology
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• 제21권5호
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• pp.372-380
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• 2022

The external corrosion control of buried pipes can be achieved by a combination of coatings and cathodic protection to maximize effectiveness. One of the factors affecting cathodic protection is the environmental soil conditions. Because soil is a kind of electrolyte, the environmental conditions of soil may be changed by the atmospheric environment. Therefore, in this study, changes in environmental soil factors by atmospheric environmental factors were monitored. In cathodic protection, on-potential and off-potential were measured from December 2021 to July 2022. The effects of external environmental factors and soil environmental factors on cathodic protection were analyzed. Changes in outdoor temperature affected soil temperature, and soil conductivity had a proportional relationship with soil humidity, but outdoor humidity and precipitation did not significantly affect humidity and conductivity of the soil. In contrast, in cathodic protection, the on-potential was affected by temperature, humidity, the conductivity of the soil, and the anode used, but the off-potential was little affected by these factors.

• Corrosion Science and Technology
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• 제16권6호
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• pp.294-297
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• 2017

For the longer service life of steel pile, cathodic protection is selected sometimes at corrosive environment. The cathodic protection design improvement was investigated in this study. The current demand for cathodic protection was calculated from the potentiostatic current monitoring of the steel specimen in the deaerated soil samples. In this study, the current distribution was studied using the Boundary Element Method (BEM) and the Finite Element Method (FEM) numerical analysis methods. The optimum layout of the anode was developed and confirmed by numerical analysis. Under the conventional design of the anode, the length of the anode hole is same as the pile length. We found that, at the bottom end of the pile, the current density is too high. When the anode hole length was 80% of the pile length, the current consumption at the end was reduced. The construction cost of anode hole drilling was decreased about 20%, as compared to the conventional design. Furthermore, the life of the anode materials could be extended by reducing the current consumption at the end section. Using this approach, the construction cost was reduced significantly without any under-protection area on the steel piles.

• Journal of Advanced Marine Engineering and Technology
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• 제37권3호
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• pp.260-265
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• 2013

Impressed current cathodic protection (ICCP) system is one of the most promising corrosion protection methods. The Effect of ICCP system can be changed at diverse conditions. Particularly, temperature and relative humidity plays a crucial role in CP (Cathodic Protection) effect. Thus, in this study, the influence of temperature and relative humidity on concrete specimens was investigated. Specimens were concrete slab type with a base of $400mm{\times}400mm$ and height of 70mm. To enhance the effect of CP system, seawater was used as an electrolyte. Used anode for ICCP system was mixed metal oxide (MMO) titanium. Test factors were natural potential, CP potential, CP current, and 4-hour depolarization potential. From this study, it could be confirm that CP potential and current were highly influenced by temperature and relative humidity.