해안지역 경관시설물 부식방지도장 시공 후 성능평가 연구 -오이도 오션프런트 공공시설물 및 조경시설물을 중심으로-

김정철 ( Kim Jungchul ),신재령 ( Shin Jaeryung ) 한국공간디자인학회 2021 한국공간디자인학회논문집 Vol.16 No.2

(연구배경 및 목적) 도시의 정체성을 나타내는 공공디자인의 활성화로, 경관시설물은 표준화된 형태와 색채를 구현하고자 철재 위 도장 방식으로의 제작설치가 급증하고 있다. 이와 함께 경관시설물의 제작과정에 녹 방지 도장을 선행함에도 불구하고 시공 후 현장에서는 시설물의 부식이 진행되거나 도장이 완전히 탈락되는 등의 문제가 대두되었고, 이는 특히 해안지역의 시설물에서 더욱 심하게 나타났다. 따라서 부식방지 도장의 시공방식 적절성에 대한 점검이 요구된다. 본 연구는 해안지역에 설치된 경관시설물의 부식방지 도장에 대한 시공 후 성능평가요소 및 측정기준을 도출하여 실증적인 평가분석을 목적으로 한다. (연구방법) 해안지역 공공시설물 부식방지 도장의 기준 및 특성을 도출하여 분석모형을 제시하고, 이를 통해 설치 후 5년 이상 경과한 경관시설물에 대한 시공 후 성능평가를 실시하였다. 평가기간은 2020년 10월부터 2021년 1월까지 진행하였으며, 부식방지도장 기법과 시공 후 녹 발생 정도를 가시평가하고 계량화하여 부식방지도장 공법에 따른 녹 발생 특성과의 관계를 분석하였다. (결과) 시설물별 가시평가 결과는 가로등 주와 가로등 분전함이 가장 높았고, 안전난간 5가 가장 낮았다. 도장 공법에 따른 부식방지 성능은 조합페인트(평균27.0)< 우레탄도장(평균52.9)< 분체 도장(평균 75.3) 순으로 높았다. 녹 방지 처리 공법별 부식방지 성능은 광명단 도장(평균22.3)< 갈바늄 도금(평균47.1)< 용융아연도금(평균68.6)< 녹 방지 무 처리(평균69.7)< 스테인리스 재질(평균88.2) 순으로 높았고, 들뜸 방지처리 공법별 부식방지 성능은 프라이머 미처리(평균 50.8)< 프라이머 전처리(평균 92.1)로 높아, 들뜸 방지처리에 따라 도막의 탈락이나 갈라짐의 차이가 크게 나타났다. 부식방지 성능이 가장 우수한 공법은 모재위에 용융아연도금 부식방지 처리 후 프라이머 처리와 분체 도장을 적용한 공법이었다. 특히, 용융아연도금 등 적극적인 녹막이 공법 위에 프라이머를 적용한 것은 우수한 부식방지 성능을 보였다. (결론) 해안지역의 경관시설물은 환경여건으로 인해 도막이 탈락되고 부식되기 쉬워, 녹막이 처리공법과 프라이머 전처리가 충실히 시공된 시설물의 부식방지 성능이 높게 나타남을 확인할 수 있었다. 시공자의 기술 숙련도에 따른 부식방지 성능차이가 있을 수 있어 각 공법별 성능 및 문제점의 비교에 한계가 있지만, 본 연구는 해안지역 등 특수한 환경여건에 부합하는 부식방지 도장 공법을 파악하여 제시함으로써 공공디자인 및 조경 등의 사업 추진 시에 경관시설물의 설계 및 시공단계의 기초자료로 쉽게 활용될 수 있기를 기대한다. (Background and purpose) With the revitalization of urban public design, the production and installation of landscape facilities with various coating methods is increasing rapidly. However, after the rust prevention coating, problems emerged at the site, such as corrosion or complete falling-offs of the coating in the landscape facilities, especially in coastal areas. Therefore, it is required to check the appropriateness of the corrosion resistant coating methods. This study aims at empirical evaluation and analysis by deriving performance evaluation elements and measurement criteria for corrosion resistant coatings of landscape facilities installed in coastal areas. (Method) In this study an analysis model was presented by deriving the standards and characteristics of corrosion resistant coatings for public facilities in coastal areas. For landscape facilities that have passed more than 5 years after installation, the corrosion resistant coating methods and the degree of rust generation after the coating work were visually evaluated and quantified to analyze the relationship between rust generation characteristics and the coating methods. (Results) As a result of the performance evaluation of corrosion protection, both 'street lighting poles' and 'street lighting distribution box' were the highest score with 94.1 points, and 'fence 5' was the lowest with 11.7 points. The performance of corrosion protection by coating method was in the order of ready mixed paint coating (27.0) <urethane coating (52.9) <powder coating (75.3). The performance of corrosion protection by anti-rust treatment method was in the order of red lead coating (22.3) <galbanum plating (47.1) <hot-dip galvanization (68.6) <non-treated (69.7) <a stainless steel material (88.2). The performance of corrosion protection by blister-prevention treatment method was in the order of non-primer treatment (50.8) <primer pretreatment (92.1), and the difference in falling-offs and cracking of the coating film was large depending on the blister-prevention treatment. The most excellent corrosion resistant method was a primer-treated coating method over an active anti-rust method such as hot dip galvanization. (Conclusions) As described above, the landscape facilities in coastal areas required a different corrosion resistant treatment than other areas because the coating film easily fell off and was corroded due to the environmental condition. As this study is not an experimental study which is conducted under the same time, environmental condition, and quality condition, there was a limit of ambiguity in comparing the performance and determining problems for each method due to the difference in corrosion protection performance according to the technical skill of a painting worker. However, it is expected that it can be easily used as basic data in the design and construction stage of landscape facilities when promoting projects such as public design and landscape architecture, as it identified and presented a corrosion resistant coating method suitable for special environmental conditions such as coastal areas.

Corrosion Behavior of Cr-bearing Corrosion Resistant Rebar in Concrete with Chloride Ion Content

Tae, Sung Ho Architectural Institute of Korea 2005 Architectural research Vol.7 No.1

Conventional studies have focused on the reduction in the water-cement ratio, the use of various admixtures, etc., to ensure the durability of reinforced concrete structures against such deterioration factors as carbonation and chloride attack. However, improvement in the concrete quality alone is not considered sufficient or realistic for meeting the recent demand for a service life of over 100 years. This study intends to improve the durability of reinforced concrete structures by improvement in the reinforcing steel, which has remained untouched due to cost problems, through subtle adjustment of the steel components to keep the cost low. As a fundamental study on the performance of Cr-bearing rebars in steel reinforced concrete structures exposed to corrosive environments, The test specimens were made by installing 8 types of rebars in concretes with a chloride ion content of 0.3, 0.6, 1.2, 2.4 and $24kg/m^3$. Corrosion accelerated curing were then conducted with them. The corrosion resistance of Cr-bearing rebars was examined by measuring crack widths, half-cell potential, corrosion area and weight loss after 155 cycles of corrosion-accelerating curing. The results of the study showed that the corrosion resistance increased as the Cr content increased regardless of the content of chloride ions, and that the Cr-bearing rebars with a Cr content of 5% and 9% showed high corrosion resistance in concretes with a chloride ion content of 1.2 and $2.4kg/m^3$, respectively.

Corrosion Resistance of Cr-bearing Rebar in Concrete with Chloride Ion Content

Tae, Sung-Ho,Lee, Han-Seung,Noguchi, Takafumi,Ujiro, Takumi,Shin, Sung-Woo The Iron and Steel Institute of Japan 2006 ISIJ international Vol.46 No.7

<P>As a fundamental study on the performance of Cr-bearing rebars in steel reinforced concrete structures exposed to corrosive environments, The test specimens were made by installing 8 types of rebars in concretes with a chloride ion content of 0.3, 0.6, 1.2, 2.4 and 24 kg/m<SUP>3</SUP>. Corrosion accelerated curing were then conducted with them. The corrosion resistance of Cr-bearing rebars was examined by measuring crack widths, half-cell potential, corrosion area and weight loss after 155 cycles of corrosion- accelerating curing.The results of the study showed that the corrosion resistance increased as the Cr content increased regardless of the content of chloride ions, and that the Cr-bearing rebars with a Cr content of 5% and 9% showed high corrosion resistance in concretes with a chloride ion content of 1.2 and 2.4 kg/m<SUP>3</SUP>, respectively.</P>

도장이 필요없는 내후성강 박스거더 상부 플랜지외부면 방식제 주입을 통한 방식공법 연구

송창영 ( Chang Young Song ) 한국부식방식학회(구 한국부식학회) 2014 Corrosion Science and Technology Vol.13 No.4

In corrosion-sensitive area of exsisting unpainted weathering steel bridge with closed box girder structure. there are some serious local corrosion problems because of rain water or dew water which can not be solved by conventional maintenance method. These problems must be technically controled because of the influence on the safety of bridge. This study is the first stage of developing the economic corrosion control manual for these local corrosion problems. Through the injecting experiment of tar sealant into the crevice of mock-up equipment, it was proofed that the corrosive sealant can be useful to corrosion control at crevice of corrosion sensitive area.

밀폐 박스거더형 무도장 내후성강 교량의 부식취약부에 대한 방식대책 연구(1)

송창영 ( Chang Young Song ),이의호 ( Eui Ho Lee ),이제현 ( Jea Hyun Lee ),박현출 ( Hyun Chul Park ),최재석 ( Jae Suk Choi ),노영태 ( Young Tae Noh ) 한국부식방식학회(구 한국부식학회) 2013 Corrosion Science and Technology Vol.12 No.3

In corrosion-sensitive areas of exsisting unpainted weathering steel bridges with closed box girder structures. there are some serious local corrosion problems because of rain water or dew water which can not be solved by exsisting maintenance methods. These problems must be controled technically because of bad. influence on the safety of bridge. This study is the first stage of developing the economic corrosion control manual for these local corrosion problems. Through the injection of tar sealant into the crevice of mock-up equipment, it was prooved that the corrosive sealant can be useful to corrosion control at crevice of corrosion sensitive area.

녹 면적율과 부식피트 형상비를 이용한 도장강재의 인장강도 추정법

장도,유훈,정영수,김인태 한국강구조학회 2023 韓國鋼構造學會 論文集 Vol.35 No.2

This study investigated a method for evaluating the residual tensile strength of corrosion-damaged painted steel by visual inspection. The tensile strength of 18 tensile test specimens and 45 corrosion-damaged model specimens with 5 percentages of rust areas (3 %, 10 %, 16 %, 33 %, and 50 %) and 3 corrosion pit shape ratios (0.25, 0.5, and 1.0) were evaluated based on the minimum cross-sectional area, and compared with the tensile test and nonlinear finite element analysis results. As a result, it was verified that the tensile strength of corrosion-damaged model specimens can be estimated within 5 % error using the minimum cross-sectional area. The tensile strength was calculated using this method for the additional 9,000 corrosiondamaged model specimens with 500 specimens each for the percentage in rust areas and the corrosion pit shape ratios, and the tensile strength reduction level was examined according to the percentage and the shape ratio. As a result, a method for estimating the tensile strength reduction level according to the percentage in rust area ratio and the corrosion shape ratio was presented, and the reduction level based on ASTM and ISO rust rating grade is also presented. 본 연구에서는 육안 상태평가에 의한 부식손상된 도장강재의 잔존 인장강도 추정법을 검토하였다. 먼저 3 %, 10 %, 16 %, 33 %, 50 %의 녹 면적율과 0.25, 0.5, 1.0의 부식피트 형상비를 인위적으로 모사한 인장실험 시편 18개와 부식손상 모델시편 45개를대상으로 최소단면적을 이용한 간이식으로 인장강도를 평가추정하여, 인장실험 및 비선형 유한요소해석 결과와 비교하였다. 그 결과간이식을 이용하여 부식손상된 강재의 인장강도를 오차율 5 % 이내로 추정할 수 있음을 검증하였다. 그리고 녹 면적율 3 %, 10 %, 16 %, 33 %, 50 %와 부식피트 형상비 0.25, 0.5, 1.0에 대해 각각 500개씩 부식손상 모델시편 9,000개를 생성하고 간이식으로 인장강도를 계산하여 녹 면적율과 부식형상비에 따른 인장강도 감소율을 검토하였다. 그 결과 임의의 녹 면적율과 부식형상비에 따른 부식손상된 인장강재의 인장강도 감소율을 추정하는 방법을 제시하였고, ASTM과 ISO의 녹 등급에 따른 인장강도 감소율도 제시하였다.

밀폐 박스거더형 무도장 내후성강 교량의 부식취약부에 대한 방식대책 연구(2)

송창영 ( Chang Young Song ),이의호 ( Eui Ho Lee ),이제현 ( Jea Hyun Lee ),박현출 ( Hyun Chul Park ),최재석 ( Jae Suk Choi ),노영태 ( Young Tae Noh ) 한국부식방식학회(구 한국부식학회) 2013 Corrosion Science and Technology Vol.12 No.4

This study is the second stage of developing the corrosion control technical manual about unpainted weathering steel bridge with closed box girder structures. This paper contains selection of corrosive sealant to apply into crevice of upper flange, injecting test of sealant at mock-up equipment with various condition, evaluation of experiment result. Through the experiment of injection of sealants into crevice of mock-up equipment, it is proved that the tar sealant injecting corrosion control method is useful to protect corrosion at box girder upper flange corroded by remaning rain water with calcium chloride.

해양환경하에 방치한 콘크리트중의 철근의 부식 추정에 대한 연구

문한영,김성수,류재석 한국콘크리트학회 1994 콘크리트학회지 Vol.6 No.2

This study was performed for the purpose of obtaining the fundamental data to establish the criterion of concrete deterioration and presuming steel corrosion of concrete structures under the environment of seawater. Steel embedded concrete specimens were exposed in seawater for 1year. The soluble chloride content in concrete, corrosion potential and steel corrosion were considered. The results show that soluble chloride content in concrete was decreased with lower water-cement ratio and with mineral admixtures. Half-cell potential is reduced with steel corrosion. Corrosion area ratio is correlative with half-cell potential. 해양환경하에 있는 콘크리트 구조물의 열화를 알아보고 철근의 부식 정도를 추정하기 위한 연구내용으로서 콘크리트 중에 철근을 묻은 공시체를 제작하여 간만의 차가 있는 해변에 1년 동안 노출시킨 상태로 시험을 실시 하여 콘크리트 중의 가용성 염분량, 철근의 자연전위값 및 철근의 부식정도에 대하여 고찰하였다. 본 연구 결과 콘크리트 중의 가용성 염분량은 물-시멘트비가 낮을수록, 혼화재를 혼입할 경우 적게 나타났으며 가용성 염분량이 클수록 철근의 부식이 크게 나타났다. 철근 부식의 정도가 심할수록 자연전위값이 감소하였으며 자연전위와 부식면적율과는 상관관계가 있음을 알 수 있었다.

이온화식 상수도관 내부 부식억제기의 철 시편에 대한 부식억제 효과측정

유미선 ( Mee-seon Yu ),양성봉 ( Sung-bong Yang ),심학섭 ( Hak-sup Shim ),이승혁 ( Seung-hyeok Lee ) 한국환경기술학회 2020 한국환경기술학회지 Vol.21 No.6

This study aimed to measure the anti-corrosion effect of the zinc ionization device in running water. Cartridges of iron coupons were immersed in 2 plastic pipes that had flown the tap water for 20 days. Initial and final concentrations of ferrous ion and zinc cation in water were measured and weight losses of each coupon were weighed. And finally corrosion area of each coupons was compared with analyzing black and white figure of each corroded coupon by use of Image J program. Average weight loss of the coupons in running water with no corrosion inhibitor is 486 ㎎/dm² for 20 days, whereas that of coupons with the corrosion inhibitor is 438 ㎎/dm² for same period. Relative anti-corrosion effect of the inhibitor was calculated to be only 9.8 % with weight loss method. Average % areas of each corroded coupons with the inhibitor or no inhibitor were 20.5 % and 43.9 %. Relative anti-corrosion effect shown by average corroded area was 53.3 %. Inhibition effect of zinc ionization device in tap water indicated that corrosion area on the iron-coupon surface was decreased largely by dissolving zinc ion from zinc metal in water even though difference of weight loss of iron coupon was very small.

염화물을 함유한 콘크리트 중의 철근방식을 위한 방청제의 효과

문한영,김성수 한국콘크리트학회 1998 콘크리트학회지 Vol.10 No.6

Under the seawater environment, the reinforced concrete structure is deteriorated due to physical and chemical attacks. The main deterioration mechanism is the chloride corrosion of reinforcing steel. The corrosion inhibitors have been used to protect the rebars from corrosion which are susceptible to chlorides in concrete. However, there is not clear conclusion about corrosion inhibitors yet. In this study, it is made the accelerated experiment with 3 kinds of corrosion inhibitors for various chloride ingresses. It is estimated corrosion inhibitors that inhibitors by Half-Cell Potential, corrosion area ratio and weight loss ratio. It is concluded that inhibitors are not effective to corrosion inhibition for excessive chloride ingress. However, the effect of inhibition is directly proportional ot contents of corrosion inhibitors in some chloride ingress. 염화물에 의한 콘크리트 중의 철근부식을 억제하기 위하여 콘크리트 배합시 방청제를 사용하는 방안이 일반적으로 많이 사용되고 있으나. 국내에서는 아직까지 방청제의 방식효과에 대한 연구는 찾아보기 어려운 실정이다. 본 연구에서는 염화물의 영향을 받는 콘크리트 중의 철근부식 억제를 위한 방안으로 방청제를 사용하여 철근의 방청효과를 알아보기 위하여 3종류의 방청제와 각각 사용량을 변화시킨 시험체를 제작하여 부식촉진 실험을 실시하였으며, 철근의 자연전위와 부시면적율을 측정하여 방식효과에 대하여 평가하였다. 그 결과 염화물의 혼입량이 지나치게 많을 경우에는 방청제의 양을 증가시켜도 방청효과가 크게 향상되지 않았으나. 염화물의 혼입량을 동일하게 사용하고 방청제의 양을 증가시켜도 방청효과가 크게 향상되지 않았으나, 염화물의 혼입량을 동일하게 방청제의 양을 증가시킬 경우에는 방청효과가 현저하게 좋아짐을 알 수 있었다.