担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jcsr.2015.11.014

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.engfailanal.2016.05.001

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Construction and Building Materials  

This study investigated the chloride-induced durability deterioration mechanism at the interface of carbon fiber reinforced polymer (CFRP) and steel joints exposure to wet-dry cycling environment, using 27 specimens with varying corrosion levels of steel and aging periods of bonded joints. Characterization including macro and microscale observation, quantification of topographical structure, analysis of surface wettability and adherent residues, were employed to understand the steel surface conditions and their relationship with durability performance under prolonged wet-dry cycles. The results indicated that various steel surface characteristics influenced the interface in both the short and long terms; however, the priority shifted from topography for new steel to cleanliness for corroded steel. As the corrosion level of the steel increased with the aging period, notable declines were observed in the joint's ultimate capacity (∼33.4 %) and its displacement (∼9.94 %) in general responses, along with decreases in maximum slip (∼31.0 %) and shorter plateaus in local responses. This corresponded to an undesirable shift in the triggering failure mode at the ends. Additionally, deterioration mechanism encompassed “foreign attacks” as external factors, marked by corrosion at the bonding edges and inward capillary diffusion of chloride ions, and “domestic unrest” as internal factors, exemplified by the development of those adherent chloride/rust residues, weakening steel-adhesive bonds, and risk of separation. Finally, a time-dependent environmental reduction factor for the capacity model was proposed and verified using collected test data.

DOI： 10.1016/j.conbuildmat.2024.137409

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Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Steel Structures  

Temperature significantly affects the galvanic corrosion behavior between carbon fiber reinforced plastic (CFRP) and carbon steel. The corrosion rate of steel components in bridges may increase at high temperatures during summer. To examine the impact of solution temperature on the galvanic corrosion between CFRP and carbon steel, electrochemical tests were conducted at different temperatures. The open circuit potential results and potentiodynamic polarization results indicated that the presence of carbon fiber to carbon steel led to increased potential and accelerated corrosion rates. Subsequently, the temperature-promoting factor was used to predict the corrosion rates of steel with galvanic corrosion based on the Arrhenius equation. Finally, the limitations of the temperature-promotion factor were analyzed theoretically.

DOI： 10.1007/s13296-024-00870-3

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出版者・発行元：Case Studies in Construction Materials  

An ionically conductive sodium polyacrylate-sodium carboxymethyl cellulose (PANa–CMC) hydrogel electrolyte was developed for the sacrificial anode cathodic protection (SACP) of carbon steel in high-humidity environments. The incorporation of varying ratios of CMC into hydrogel formulation enhanced the water retention capacity, adhesion strength, and electrochemical performance, making it suitable for SACP applications. Particularly, PANa-5% CMC hydrogels demonstrated a current density of approximately 3 μA/cm², inhibited passive corrosion product formation, and sequestered metal ions from anodes, thus minimizing contamination. These findings highlight the substantial potential of PANa–CMC hydrogels as electrolytes, expanding the application of the SACP method to atmospheric environments.

DOI： 10.1016/j.cscm.2023.e02742

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出版者・発行元：Journal of Building Engineering  

The effects of a newly developed nozzle type, with divergent flow, and abrasive particle size on the surface preparation properties of steel substrate using abrasive water-jet treatment (AWT) were analyzed. The corrosion and chloride removal efficiencies were evaluated by applying this technique to parts of severely corroded steel structures. The evaluation of the surface characteristics of the treated specimens included analysis of the treatment area, maximum erosion depth, surface roughness profile, and residual abrasive material quantity. The corrosion removal efficiency was assessed using surface salinity measurements and SEM-EDX analysis. The experimental results demonstrated that the application of the developed divergent nozzle and smaller abrasive particle sizes in the AWT process resulted in an expanded treatment range and effective prevention of excessive erosion depth and surface roughness. Additionally, ultra-high-pressure water with abrasives completely eliminated corrosion products and chlorides present on both the surface and interiors of the corroded steel surface, achieving a cleanliness level exceeding Sa 3. This process prevented the formation of flash rust on the cleaned surface for up to 24 h and prolonged the time before the reoccurrence of corrosion on the treated surface. To summarize, the AWT with a divergent nozzle and smaller abrasive particles creates the most ideal surface preparation characteristics for subsequent coating and provides higher surface cleanliness suitable for practical engineering applications.

DOI： 10.1016/j.jobe.2024.108623

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Electrochemical Science  

In the pursuit of sacrificial anode cathodic protection (SACP) for closed-section steel structures exposed to atmospheric conditions, a cotton-like fiber serves as the electrolyte carrier. The efficacy of this approach was validated through assessments of water absorption, retention, electrochemical properties, and SACP trials. The cotton-like fiber exhibited notable hydrophilic characteristics, absorbing nearly seven times its weight of the electrolyte and retaining over 50% of its maximum water absorption capacity after 15 days. Furthermore, the ionic conductivity of the fiber, when fully saturated with 0.1 wt% NaCl aq, was nearly twice that of the same concentration solution without fibers, diminishing as the electrolyte content decreased. Additionally, the open-circuit potential (OCP) of the Al-3Zn sacrificial anode was approximately −0.2 V relative to steel. Moreover, Nyquist plots revealed that electrodes in fibers were more resistant to dissolution compared to those in 0.1 wt% NaCl aq. In the SACP tests, the combination of cotton-like fibers with the Al-3Zn anode exhibited a protective performance for steel members, as assessed by the current density, instant-off potential, and steel surface conditions.

DOI： 10.1016/j.ijoes.2024.100518

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出版者・発行元：Corrosion Science  

The corrosion interaction mechanism of carbon steel was studied to address the mutual interference of carbon steels under coating defects in the atmospheric environment. The findings revealed that the electrochemical interactions between the carbon steels were primarily influenced by the solution resistance, cathode area, and cathode-to-anode area ratio. In addition, the upper limit of the accelerating effect of the macrocell current on the anodic corrosion rate was determined by theoretical deduction. Finally, the corrosion-accelerating effect of the macrocell current was determined to assess the corrosion rate of carbon steels with electrochemical interactions under defects.

DOI： 10.1016/j.corsci.2023.111730

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Construction and Building Materials  

To assess the impact of corrosion on steel and the effectiveness of surface preparation techniques on the bonding behavior between carbon fiber reinforced polymer (CFRP) and steel, thirty bonded joint specimens were examined. These specimens were based on three distinct corrosion levels of steel and three conventional surface preparation techniques. Furthermore, various evaluation methods were employed to understand the steel surface characteristics, encompassing macro and microscale observations, analysis of topographical structures, and quantification of surface evaluation indices. These were performed to determine their correlations with the interfacial stress behavior. The findings revealed that when the target for repair shifted from a new steel substrate to a corroded one, the synergistic performance at the steel-adhesive interface decreased. This led to a decrease in the maximum shear stress at the plate end, and there was also an undesirable shift in the mode of failure. Both test parameters (i.e., the corrosion level and surface preparation), synergistically determined the surface cleanliness, topography, and bonding defects, all three of which directly influenced the bonding behavior. Finally, an improved model for predicting the debonding capacity of CFRP-corroded steel bonded joints was introduced, incorporating surface damage (k1) and surface topography (k2) coefficients. This model's applicability was also verified by collecting other test data from available literature.

DOI： 10.1016/j.conbuildmat.2023.134279

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 土木学会  

<p>　鋼部材と炭素繊維シートの接着特性は，素地調整法や養生温度などの施工条件により変化する．しかし，これらの条件が炭素繊維シートの接着特性に及ぼす影響については不明な点が多いため，補修・補強の設計や施工条件を最適化することは困難である．本研究では素地調整法が鋼素地の表面性状と付着特性に及ぼす影響を明らかにした上で，鋼板と炭素繊維シートのせん断強度を検討した．また，養生温度が含浸樹脂の硬化速度，機械的性質，熱特性および繊維への浸透性に及ぼす影響を検討した．さらに，初期等温硬化モデルを構築し，熱履歴に関する樹脂のガラス転移過程を推定することで，後硬化による樹脂の各物性の改善効果を評価した．これらの知見に基づき，CFRP補強部の接着性能を向上させるための施工条件を提案した．</p>

DOI： 10.2208/jscejj.23-00250

CiNii Research

記述言語：英語   出版者・発行元：Kyushu Association for Bridge and Structural Engineering  

Over the past decade, CFRP strips have been increasingly used worldwide to repair or strengthen steel bridges. However, a large number of researchers use uncorroded steel as the target object before attaching CFRP. This approach is somewhat unreasonable as most steel members that require repair have suffered corrosion damage to different degrees. Additionally, before CFRP retrofitting, the corroded steel should be cleaned first, and the level of steel surface cleanliness is dependent upon the rust-removal method used. Even so, it is difficult to entirely remove all corrosion rust from the steel surface in practical applications. This means that in some cases, interfacial defects are almost inevitably going to occur. Therefore, in this study, the effects of interfacial defects on the corroded steel surface, following three kinds of rust-removal methods (acid solvent, disk sander, and abrasive blast), were primarily evaluated by means of the debonding shear stress at the plate end. In addition, several interfacial defects such as air bubbles, kissing bonds, and secondary rust, were observed based on surface and cross-section analyses using SEM-EDX, respectively. Varying amounts of rust residues tend to induce rust-back, and over time, cause visible under-film corrosion based on the observation of fracture interface. These observations can also provide strong evidence to explain why there is a certain reduction in strengthening effectiveness when using CFRP strips to repair corroded steel, compared to uncorroded steel. Finally, the authors argued that the disk sander in a single way for rust removal was insufficient in the case of repairing corroded steel members with a lot of relatively deep corrosion pits. Because severe rust residues and under-film corrosion observed was likely the primary reason for the adhesive's separation from the steel surface, thereby causing very premature failure of CFRP retrofitting.

DOI： 10.60345/kabse.39.0_85

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Structures  

Resin-impregnated carbon fiber fabric reinforced polymer (CFRP) is a novel material for steel structure reinforcement, but its performance is influenced by moisture and temperature. This study investigates the irreversible degradation of CFRP–steel adhesive joints in a hydrothermal setting, focusing on resin hydrothermal aging behavior. Moisture absorption tests, Fourier-transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) were conducted to assess moisture's impact on resin matrix's properties. Results indicate that moisture absorption behavior is partially reversible through physical drying, while hydrolysis resulting from moisture absorption is irreversible. The partially reversible aspect of moisture absorption leads to a partial restoration of the thermodynamic properties of the resin matrix. Additionally, the mechanical performance of resin specimens and CFRP-steel adhesive joints in hydrothermal conditions was assessed using tensile and pull-off tests. Findings show that elevated temperatures accelerate the moisture absorption rate of resin while increasing the maximum moisture absorption capacity. The moisture absorption affects the fracture surface morphology of the resin matrix, with aging time negatively correlated with adhesion strength. Compared to the hydrothermally aged state, there is a slight recovery in the mechanical performance of CFRP–steel adhesive joints after drying desorption. The saline environment with no significant promotion aging compared to the distilled water environment. These findings provide insights for evaluating CFRP–steel adhesive joints’ durability in atmospheric or marine environments.

DOI： 10.1016/j.istruc.2023.105581

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出版者・発行元：Construction and Building Materials  

Atmospheric corrosion is one of the most critical issues in steel structures. To improve the structure's durability and reduce its cost, hot-dip coatings are a significant method for steel protection. The corrosion behavior of Al-based hot-dip coatings has been extensively studied. Galvanic corrosion usually occurs when steel members are coated with different hot-dip coatings and placed in direct contact. In this study, galvanic corrosion of an Al coating in contact with a 55Al–Zn coating in an atmospheric environment was investigated through electrochemical and exposure tests. The galvanic corrosion and its mechanism were studied based on open circuit potential (OCP), galvanic current, and X-ray diffraction (XRD) analyses. This study verified the galvanic corrosion of bolt joints in the actual application by the long-term exposure test. The results suggests that 55Al–Zn coating is a good substitute for Zn coating used for bolted joints in contact with Al-coated steel plate.

DOI： 10.1016/j.conbuildmat.2023.132694

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記述言語：英語   出版者・発行元：公益社団法人 腐食防食学会  

<p>高湿度環境や海洋環境における炭素繊維補強された鋼構造物では，ガルバニック腐食が発生しやすくなる．本研究では，炭素繊維と普通鋼の接触によるガルバニック腐食に影響を及ぼす主要因である，一方向性炭素繊維（CF）の電気化学的特性，異種材料間の接触状態，および環境温度について検討した．その結果，炭素繊維と炭素繊維束は，繊維方向に対して均質な抵抗器と見なせることを明らかにした．ただし，炭素繊維が金属粗面に接触する場合には，異種材料間の導電経路が最適化され，接触面積が増大することで，表面抵抗が著しく低下する．また，アレニウス方程式に基づき，高温環境における腐食促進作用を説明するための簡略化モデルを構築し，温度変化がガルバニック腐食に及ぼす影響は，普通鋼の腐食に比して顕著であることを明らかにした．</p>

DOI： 10.3323/jcorr.72.202

CiNii Research

出版者・発行元：Lecture Notes in Civil Engineering  

It is commonly duplex layers partially placed on a thermal sprayed coating when narrow parts are difficult to thermal spray. In a previous study, it was shown that when the duplex layer has a defect, thermal spray coating deteriorates faster than the single-layer coating. It is critical to evaluate and anticipate the occurrence and progression of duplex layer degradation and blistering in order to execute effective maintenance management for steel structures. In this investigation, specimens with duplex layers were exposed to the atmosphere and corrosion environment was monitored using ACM-type corrosion sensors and temperature-humidity sensors. Based on these findings, we proposed a method to evaluate the deterioration and blister progression of duplex layer between Al-5Mg thermal sprayed coating and heavy-duty paint coating in an environment without rain-washing action of adhered sea salt.

DOI： 10.1007/978-981-19-4293-8_38

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出版者・発行元：Lecture Notes in Civil Engineering  

A high-power continuous-wave laser is applied in this study as a replaceable surface treatment method for steel structures. Various forms of corrosion pits will affect the laser treatment efficiency for surface preparation of severely corroded steel structures. In order to evaluate the effect of laser treatment on the steel surface with corrosion pits, carbon steels with artificial pits of various depths and widths were performed and treated by laser irradiation. SEM-EDX analysis distinctly identified laser-treated areas under conditions by mapping elements. Results indicate the laser beam can reach the bottom of pits, promising cleaning efficiency of laser irradiation is still worth expecting.

DOI： 10.1007/978-981-19-4293-8_34

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出版者・発行元：Lecture Notes in Mechanical Engineering  

A new cathodic protection method including a sacrificial anode and a water swelling rubber was developed and applied to steel members in boundary with ground in the environment of stagnant water and dryness. To ensure applicability, the water swelling rubber was considered as the electrolyte carrier. The reliabilities in water absorption and retention capacity of the rubber were verified by an immersion and drying test. In addition, an electrochemical test was conducted to evaluate the applicability of the water swelling rubber under different environmental conditions. The test results demonstrated that the water absorption and retention performance of the rubber are associated with electrolyte concentration. And the method with the rubber is suitable for immersed and dry environments.

DOI： 10.1007/978-981-19-6841-9_22

Scopus

記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

<p>　鋼道路橋において，溶射皮膜上に塗装が塗布され，重ね皮膜になる場合があるが，その重ね皮膜の耐久・防食特性については不明な点が多い．そこで，本研究ではAlとZnの溶射と重防食塗装の重ね皮膜部の耐久・防食特性を解明するために，クロスカット傷を導入した溶射単膜，および溶射と塗装の重ね皮膜部を有する鋼板試験体を用いて複合サイクル腐食促進試験を行った．また，重ね皮膜部の膨れ性状の測定，分極特性などの電気化学測定，SEM-EDXによる断面元素分析およびXRDによる生成物の同定分析を実施した．これらの結果から，溶射と塗装の重ね皮膜では，Al溶射の重ね皮膜がZn溶射に比べて早期に劣化し，耐久性が低下することなどを明らかにした．また，塩類に曝される腐食性の高い環境におけるAlとZnの溶射と塗装の重ね皮膜の劣化機構を示した．</p>

DOI： 10.2208/jscejj.22-00288

CiNii Research

出版者・発行元：International Journal of Steel Structures  

Steel box girders are easily subjected to fatigue cracking under the vehicle loading, and the crack initiating from arc notch of diaphragm is one of the typical fatigue details. The stress characteristics of diaphragm and U-rib in real bridge under the vehicle loading were analysed, as well as the deformation characteristics. Experimental work on fatigue crack propagation and bearing capacity was conducted. Simulations using the finite-element method were undertaken, and the crack propagation behaviours were studied. It is found that the out-of-plane deformation is the main cause of crack propagation at arc notch of diaphragm in real bridge. Fatigue testing data of 9 diaphragm-rib specimens carried out by the vibration fatigue test system and results of FEM simulations show that the rate and path of fatigue crack propagation changed significantly during the fatigue crack propagation. The fatigue crack initiates as a tensile-shear mixed mode crack and turns to single tensile mode with the increase of crack length.

DOI： 10.1007/s13296-022-00637-8

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Composites Part B: Engineering  

This study focused on the interfacial bond behavior of steel-CFRP (carbon fiber-reinforced polymer) adhesion joint associations with different steel surface treatments through typical pull-off and shear tests. The specimens were fabricated based on wet layup laminating CFRP and clean/corroded steel plates. Four types of surface treatments and two kinds of pre-coating processes were investigated to optimize the interfacial bond behavior. Meanwhile, the conventional rust removal methods were also studied by clarifying the physical and chemical characteristics of steel surfaces. Test results evaluated the topography, microstructure, and surface composition of clean and corroded steel specimens, and qualitatively established their relation to bonding behaviors and failure modes. A strong correlation existed between the surface geometry properties and the tensile/shear strength, however, for clean and corroded steel surfaces their fracture mechanisms differ. Various physical property parameters of the corroded surface related to surface treatment will further affect the bond performance. The corresponding adhesion mechanisms were mathematically demonstrated based on the surface energy principle. The present experimental results provide new insights into the interfacial bond mechanism between corroded steel structures and adhesive or CFRP composites.

DOI： 10.1016/j.compositesb.2022.110280

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.4028/p-9jgv59

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Engineering Failure Analysis  

Finger-type expansion joints (FJs) have been extensively used in highway bridges and are exposed to the repeated impacts of traffic loading and corrosive environments. In this study, the corrosion and cracking behaviors of FJs serving in bridges for more than 25 years were investigated. The microstructure, electrochemical properties, and dynamic response of the FJs were investigated to analyze the fracture mechanism. The results showed that the crack-induced mechanisms of the two main failure modes were different because the synergistic effect of corrosion with residual stress changed depending on the degree of corrosion. First, considerable residual tensile stress, which enhanced the effective stress range, was the critical cause of fatigue crack initiation in the less corroded heat-affected zone (HAZ). Second, the dominant mechanism for cracking was the applied stress to the severely eroded FJ bottom, which was accelerated by galvanic corrosion. Crack-inducing factors included a combination of stress concentration and dynamic springback behavior.

DOI： 10.1016/j.engfailanal.2021.105894

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出版者・発行元：Lecture Notes in Civil Engineering  

Hot-dip Al coating is an effective and economical protection method for steel structures. Hot-dip Al coated steel members have also been used in the case that contact with concrete. Al is an amphoteric metal that can react with acid and alkaline. Concrete is an alkaline material. The corrosion behavior of hot-dip Al coating contact with concrete is studied by measurement OCP and monitoring the change of pH during the hardening process of concrete. And the atmospheric test that simulates the actual structures. The corrosion products are analyzed by the diffraction of X-rays (XRD). The hot-dip Al coating can be dissolved during the hardening process. With the decreasing pH of concrete, the Al coating also has a relatively stable due to the passivation effect. In the dry and no stagnant water environment, the hot-dip Al coating has a better anti-corrosion behavior due to the passivation and shielding effect of complex calcium-aluminum compounds.

DOI： 10.1007/978-981-16-6932-3_21

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：MDPI AG  

<jats:p>The effects of blasting with metallic steel grit and non-metallic alumina grit on steel surface characteristics were evaluated. These abrasives are generally used at construction sites and in vacuum blasting. Milled steel specimens were used to investigate the effect of the blasting conditions on surface properties. The effect of difference in surface properties on the adhesion strength and corrosion behavior were measured through adhesion tests, polarization curves, and electrochemical impedance spectroscopy. The limitations of blasting were evaluated using corroded steel specimens, as were the effects of corrosion products, salts, and abrasive material remaining on the blasted steel surface on the adhesion and corrosion resistance of paint. Steel grit more effectively increased the surface roughness than alumina grit; however, with both abrasive materials, the roughness increased with the blast projection angle. However, in the case of alumina grit, some abrasive material remained on the surface; thus, the actual roughness not including the residual abrasive material was more complex and greater than that of the sample blasted with steel grit. According to the adhesion strength test of painted and unpainted specimens, the adhesion force improved with increasing surface roughness and residual abrasive materials. Further, surface roughness was linearly correlated with the adhesion strength of unpainted specimens for both abrasive materials with blasting, and the adhesion strength force with alumina grit was approximately 1.4 times higher than that with steel grit, suggesting that increased roughness and residual abrasive material could benefit adhesion. According to the electrochemical test results, lower roughness and increased residual abrasive material owing to alumina grit on the steel surface enhanced the surface corrosion resistance, confirming the benefit of residual materials. Grinding left behind corrosion products and salts under the steel, resulting in the recurrence of rusting. However, the residue from blasting with alumina suppressed corrosion, thus improving the adhesion and corrosion resistance of the paint.</jats:p>

DOI： 10.3390/met11122065

CiNii Research

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 腐食防食学会  

<p>飛来海塩環境における鋼構造物において，滞水しやすい部位や結露などにより乾湿環境に曝される部位に重度の腐食損傷が生じている．これらの腐食は，複数の塗膜傷部が水膜により電気的に短絡することで，相互干渉しながら進行することが多い．本研究では，近接する2つの塗膜傷を模した試験体を大きい側の塗膜傷部の電極を分割することで製作し，その塗膜傷領域内に相当する鋼素地の腐食電流を測定した．また，この傷部の鋼素地と近接する傷部の鋼素地間のマクロセルの腐食電流を測定した．この結果から，滞水と乾湿繰り返しの環境で近接した塗膜傷部の鋼素地間の腐食特性を明らかにした．</p>

DOI： 10.3323/jcorr.70.271

CiNii Research

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Science and Business Media {LLC}  

DOI： 10.1007/s13296-021-00485-y

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 土木学会  

<p>　大気環境の鋼構造物では，ジンクリッチ塗膜を防食下地とした重防食塗装系が用いられている．しかし，滞水部位や乾湿が繰り返される部位におけるジンクリッチ塗膜の防食特性については不明な点が多い．また，塗膜傷間における鋼素地の電気化学機構については検討されていない．本研究では滞水環境と乾湿繰り返しの環境に着目して，有機系と無機系のジンクリッチ塗膜の傷部鋼素地に対する防食特性を電気化学的に解明することを目的とした．そのために，塗膜傷を模したモデル試験体の交流インピーダンスと腐食電流を測定した．これらの結果から，無機系ジンクリッチ塗膜では，傷径が比較的小さい場合には亜鉛末による犠牲陽極作用や化合物による防食作用が生じるが，有機系塗膜については亜鉛末による防食作用が発現しにくいことを示した．</p>

DOI： 10.2208/jscejseee.77.3_439

CiNii Research

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 土木学会  

<p>　本研究では飛来海塩環境におけるAl-5Mg合金溶射と重防食塗装の取合部の耐食・防食特性を明らかにするために，帯状の鋼素地露出部を導入した溶射皮膜と塗膜の皮膜重ね部，および溶射皮膜と塗膜の突合せ部を有する鋼板試験体の大気暴露試験を行った．また，大気暴露した試験体の溶射皮膜の膨れ性状や交流インピーダンスの測定，SEM-EDXやEPMAなどによる元素分析を実施した．これらの結果から，Al-5Mg溶射皮膜と塗膜の重ね部における鋼素地露出部からの溶射皮膜は，腐食環境によらず溶射皮膜のみの場合に比べて早期に劣化し，防食性能が低下すること，また，この傾向は付着海塩の雨洗作用がある環境に比して，雨洗作用が無い環境が強いことなどを明らかにした．</p>

DOI： 10.2208/jscejseee.77.1_180

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier {BV}  

DOI： 10.1016/j.conbuildmat.2019.117405

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 土木学会  

<p>　飛来海塩などの腐食性の高い環境に曝される鋼構造物において，塗膜傷を起点とする局部腐食が多数報告されている．この塗膜傷部の腐食は，雨水や結露などの水膜形成により電気的に短絡することで，相互干渉しながら進行する．本研究では鋼構造物の雨水が滞水する部位と結露により乾湿が繰り返される部位に着目して，近接する複数の塗膜傷間における鋼材の初期腐食の電気化学特性を解明することを目的とした．そのために，塗膜傷を模した複数の電極を有するモデル試験体を製作し，そのマクロセル腐食電流を経時的にモニタリング測定した．その結果から，滞水部位における3つの塗膜傷の電気化学特性を解明した上で腐食電流密度の推定手法を提案した．また，乾湿が繰り返される部位では，大きい傷に比して小さい傷の腐食が進行しやすいことを明らかにした．</p>

DOI： 10.2208/jscejseee.76.3_467

CiNii Research

担当区分：筆頭著者,　最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Trans Tech Publications, Ltd.  

DOI： 10.4028/www.scientific.net/MSF.972.235

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 土木学会  

<p>　本研究では NaCl による高腐食性環境におけるAl-5Mg合金溶射と重防食塗装の重ね部における耐食・防食の基本特性を明らかにするために，クロスカットを導入した鋼板試験体の複合サイクル腐食促進試験を行った．また，塗膜の交流インピーダンス測定，光沢度測定およびSEM-EDXによる元素分析なども実施した．これらの結果から，Al-5Mg合金溶射と重防食塗装の重ね部における鋼素地露出部からの溶射皮膜の劣化は，溶射皮膜のみの場合に比べて早期に発生・進行すること，クロスカット部における析出物の生成機構などを明らかにした．また，本複合サイクル腐食促進試験の条件では，溶射皮膜劣化後も，重防食塗装の上塗り塗膜は劣化しないことなどを示した．</p>

DOI： 10.2208/jscejseee.75.280

CiNii Research

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 腐食防食学会  

<p>塗装鋼構造物において，雨水が滞水する部位や結露する部位では，複数の塗膜傷部が電気的に短絡することで，相互干渉しながら腐食が進行する．本研究では滞水環境を対象として，径の異なる塗膜傷間が相互干渉する場合の鋼材電気化学機構を検討することを目的とした．そのために，複数の電極を有するモデル試験体を製作して，その電極間の腐食電流を測定した．この測定結果から径の異なる電極が存在する場合には，径の大きい側と小さい側の電極がそれぞれアノードとカソードに固定されることで，腐食が進行することを明らかにした．また，電極径がある程度小さい場合，近接する電極の面積比とマクロセル腐食の電流密度には，線形の相関関係があることを示した上で，これらの関係を定式化した．</p>

DOI： 10.3323/jcorr.67.466

CiNii Research

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 腐食防食学会  

<p>鋼構造部材の地際部では，地際部に雨水など環境因子が長時間滞留することで，進行性の高い局部腐食が発生しやすい．この局部腐食が生じることで，部材破断に至った事例が多数報告されている．本研究では鋼部材の地際部における腐食性を評価するために著者らが考案した腐食センサの出力特性とその実用性に関する基礎的検討を目的とした．そのために，NaCl水溶液による気液界面を含む模擬環境におけるセンサの出力特性について検討した．また，同環境で裸普通鋼板を用いた室内暴露試験を実施することで，その試験結果とセンサ出力に基づき算出した腐食深さを比較・検討した．さらに，腐食センサを用いた鋼材の経時腐食深さの評価方法を提案した．</p>

DOI： 10.3323/jcorr.67.404

CiNii Research

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.4028/www.scientific.net/KEM.774.619

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.4028/www.scientific.net/KEM.754.55

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 土木学会  

本研究ではNaClによる高腐食性環境におけるAl-5Mg合金溶射と塗装の取合部の耐食・防食特性を明らかにするために，線・帯状の鋼素地露出部を導入した溶射皮膜と塗膜の重ね部あるいは突合せ部を有する鋼板試験体の複合サイクル腐食促進試験を行った．また，塗膜の交流インピーダンス測定やEPMAによる元素分析なども実施した．これらの結果から，Al-5Mg合金溶射と重防食塗装の重ね部における鋼素地露出部からの溶射皮膜の劣化は，溶射皮膜のみの場合に比して早期に発生・進行すること，また，溶射皮膜が鋼素地露出端部から劣化・剥離した後に，溶射皮膜による犠牲陽極作用と酸化物の皮膜保護性による防食性能が著しく低下することを明らかにした．さらに，鋼素地露出幅が増加するほど，溶射皮膜が早期に劣化し，防食性能が低下することなどを示した．

DOI： 10.2208/jscejseee.73.496

CiNii Research

記述言語：中国語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.measurement.2016.06.040

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1061/(ASCE)CF.1943-5509.0000460

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1179/1432891714Z.000000000465

担当区分：筆頭著者   記述言語：中国語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3876/j.issn.1000-1980.2014.05.011

担当区分：筆頭著者   記述言語：中国語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3876/j.issn.1000-1980.2014.05.010