STUDY ON CATHODIC PROTECTION DESIGN OF OFFSHORE STRUCTURE

海上结构物阴极保护设计研究

• 批准号: 61460152
• 负责人: NAGAI KIN-ICHI
• 金额: $ 2.18万
• 依托单位: HIROSHIMA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-61460152/
• 关键词: SACRIFICAL ANODE; FINITE ELEMENT METHOD; ANTICORROSION DESIGN; CATHODIC PROTECTION; OFFSHORE STRUCTURE; 海洋構造物; 数値解析; 境界要素法; 温度; 流速; ラプラスの方程式

As the numerical method to analyse the potential distribution in a protection cell with a sacrifical anode, the finite element method adding the conservation law of protection current has already been proposed by the authors. In order to investigate the applicability of the numerical method to anticorrosion design of marine structures protected with a sacrifical anode, potential distribution of real structures built in harbors were analysed by the numerical method and compared with measured values.The results are summerized as follows:(1) The numerical method is applicable to estimate potential distribution in real marine structures.(2) the time elapsed since the cathodic protection is started should be specified in the estimation of the potential, because the polarization characteristics of steel in sea water changes with time. If the polarization characteristics correspond to the elapsed time is given to the estimation, the potential distribution estimated by the numerical method is in good agreement with the measured results.(3) the cathodic polarization curve, of which the surface resistance of steel in sea water is 6<OMEGA>.m^2, is suitable for the anticorrosion design of marine steel structures.

作为分析阳极保护槽内电位分布的数值方法，作者已提出了加入保护电流守恒定律的有限元法。为了探讨数值计算方法在海洋结构物阳极防护设计中的适用性，采用数值计算方法对真实的港内结构物的电位分布进行了分析，并与实测值进行了比较，结果表明：（1）数值计算方法适用于估算真实的海洋结构物的电位分布。(2)由于钢在海水中的极化特性随时间而变化，因此在电位估算中应规定阴极保护开始后所经过的时间。如果将极化特性与经过时间相对应的极化特性用于估计，则由数值方法估计的电位分布与测量结果吻合良好。(3)其阴极极化曲线在海水中的表面电阻为<OMEGA>6.m^2，适用于海洋钢结构的防腐设计。

项目成果

永井欣一,吉田光正: 西部造船会々報. 73. 114-121 (1987)

Kinichi Nagai，Mitsumasa Yoshida：《西方造船协会杂志》73. 114-121 (1987)。

岩田光正: 日本造船学会論文集. 162. 480-486 (1987)

Mitsumasa Iwata：日本造船学会论文集 162. 480-486 (1987)。

MITSUMASA IWATA, KIN-CHI NAGAI, HISAYUKI UTO: "NUMERICAL ANALYSIS OF POTENTIAL DISTRIBUTION IN HARBOR STRUCTURES UNDER CATHODIC PROTECTION USING SACRIFICAL ANODE" JOURNAL OF THE NAVAL ARCHITECTS OF JAPAN. 162. 480-486 (1987)

MITSUMASA IWATA、KIN-CHI NAGAI、HISAYUKI UTO：“使用牺牲阳极进行阴极保护下港口结构电势分布的数值分析”日本海军建筑师杂志。