Study on Estimation Method of Durability for Reinforced Concrete Structures under Chloride Contaminated Environment

氯化物污染环境下钢筋混凝土结构耐久性评估方法研究

• 批准号: 13650636
• 负责人: YAMADA Yoshitomo
• 金额: $ 1.6万
• 依托单位: University of the Ryukyus
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13650636/
• 关键词: Chloride Ions; Air Born chlorides; Penetrating Process of Chloride Ions; Durability; Finite Element Method; Neural-Network; 劣化予測; 鉄筋腐食状態; 腐食限界塩化物イオン量; 飛来塩分量; HSMAC法; 鉄筋コンクリート構造物

In order to perform rational durability design and proper diagnosis of reinforced concrete structures under chloride contaminated environment, it is necessary to understand the characteristics of air born chlorides and clarify the penetrating process of chloride ions into concrete. Also, it becomes important to evaluate the amount of chloride ions around steel reinforcement quantitatively relating with time. Therefore, this research presents experimental and analytical studies on the characteristics of air born chlorides and the penetrating process of chloride ions into concrete.The outline of the discussion about research result is as following;The background of this research and wide survey of related researchers are presented in order to show the purpose of this research.1. The advection and diffusion equation of air born chlorides proposed here takes account of the surface roughness and the shielding effect due to barriers. The analytical results of the proposed equation are obtained by using the finite element method (F.E.M.), and the results are compared to the field data. It is confirmed that they are closely related each other qualitatively and quantitatively.2. This paper proposes an evaluating method of chloride ion content in concrete by the Neural-Network. Output data from the Neural-Network are confirmed to present proper values which are closely related to the measured data.Recently, premature deterioration of existing reinforced concrete structures has become a public concern and future reinforced concrete structures are required to have durability. Therefore, the results from this research are believed to give valuable information for durability design and diagnosis of reinforced concrete structures under chloride contaminated environment.

为了对氯化物污染环境下的钢筋混凝土结构进行合理的耐久性设计和正确诊断，有必要了解空气中氯化物的特性并阐明氯离子渗入混凝土的过程。此外，定量评估钢筋周围氯离子的含量与时间的关系也变得很重要。因此，本研究对空气中氯化物的特性以及氯离子渗入混凝土的过程进行了实验和分析研究。研究结果讨论的概要如下：本研究的背景和相关研究人员的广泛调查提出以表明本研究的目的。 1．这里提出的空气氯化物的平流和扩散方程考虑了表面粗糙度和障碍物的屏蔽效应。利用有限元法（F.E.M.）获得了所提出方程的解析结果，并将结果与​​现场数据进行了比较。证实它们在质和量上都密切相关。 2．本文提出了一种利用神经网络评价混凝土中氯离子含量的方法。神经网络的输出数据被确认呈现与测量数据密切相关的正确值。近来，现有钢筋混凝土结构的过早损坏已成为公众关注的问题，并且要求未来的钢筋混凝土结构具有耐久性。因此，本研究结果将为氯化物污染环境下钢筋混凝土结构的耐久性设计和诊断提供有价值的信息。