Study on deterioration of concrete subjected to sulfate attack in cold regions and its countermeasures

寒冷地区混凝土硫酸盐侵蚀劣化及对策研究

• 批准号: 13450178
• 负责人: MIURA Takashi
• 金额: $ 5.82万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13450178/
• 关键词: Concrete; Combined deterioration; Frost damage; sulfate; Sulfuric acid; Sea water; Prediction of deterioration; Soaking test; 中性化深さ; 侵食深さ; モルタル; 塩化ナトリウム; モルタル侵漬試験; 硫酸濃度

In this study, the deterioration of concrete structures exposed to sulfuric acid, sulfate, and chloride were researched. Additionally the patterns with the combined deterioration between these factors and freeze/thaw attack and its mechanism were investigated. From these experiments, the following conclusions were drawn.The testing results of soaking mortar and concrete specimens in sulfuric acid solution revealed that the deterioration of concrete is more accelerated with low water-cement ratio compared to high water-cement ratio. Further it was indicated that the deterioration rate of concrete by sulfuric acid was predicted as a function of water-cement ratio, sulfuric acid concentration, and the period of soaking in sulfuric acid.From the testing results with the combined deterioration between seawater and freeze/thaw attack, it was recognized that the influence of sodium chloride in seawater on the deterioration is remarkably more than that of magnesium sulfate and the deterioration pattern is mainly governed by scaling from the concrete surface. On the other hand, it was confirmed that the combined deterioration between sulfuric acid and freeze/thaw attack induces remarkable scaling and the mass loss caused by scaling increases as water-cement ratio and sulfuric acid concentration increase. Further it was shown that this type of combined deterioration could be evaluated by superimposing the deterioration curves by the sulfuric acid attack considering the scaling rate at low temperatures and freeze/thaw attack.Finally it was recognized that the internal evaluated strength distribution of concrete by needle penetration testing method includes much variation depending on the deterioration pattern and this testing method is not always suitable for evaluating concrete strength.

在这项研究中，研究了暴露于硫酸，硫酸盐和氯化物的混凝土结构的恶化。此外，研究了这些因素与冻结/解冻攻击及其机制之间综合恶化的模式。从这些实验中，得出了以下结论。硫酸溶液中浸泡砂浆和混凝土标本的测试结果表明，与高水精比率相比，混凝土的恶化更加随着水泥浆比的速度加速。 Further it was indicated that the deterioration rate of concrete by sulfuric acid was predicted as a function of water-cement ratio, sulfuric acid concentration, and the period of soaking in sulfuric acid.From the testing results with the combined deterioration between seawater and freeze/thaw attack, it was recognized that the influence of sodium chloride in seawater on the deterioration is remarkably more than that of magnesium硫酸盐和恶化模式主要通过从混凝土表面缩放来控制。另一方面，已经证实，硫酸与冻结/解冻攻击之间的综合恶化会引起显着的缩放，并且随着水污质比和硫酸浓度的增加，缩放量的质量损失增加。进一步表明，可以通过硫酸攻击叠加劣化曲线来评估这种类型的劣化，考虑到低温下的缩放速率和冻结/解冻攻击，硫酸攻击和冻结攻击的缩放率。在本文中，人们认识到，内部评估的强度通过针刺测试的方法包括在此测试模式下进行的，并且不始终在适当的测试方法上进行了多种变化。

项目成果

吉田祐介: "硫酸によるコンクリートの劣化に及ぼす粗骨材量の影響"平成15年度土木学会東北支部技術研究発表会講演概要集. 600-601 (2004)

Yusuke Yoshida：“粗骨料用量对硫酸引起的混凝土劣化的影响”2003年日本土木学会东北分会技术研究报告摘要600-601（2004年）。

青柳 直樹: "硫酸環境にさらされたコンクリートの劣化状態に関する研究"平成13年度東北支部技術研究発表会講演概要. (印刷中). (2002)

Naoki Aoyagi：“暴露于硫酸环境下的混凝土的劣化状态的研究”2001 年东北分部技术研究报告摘要（2002 年出版）。

青柳直樹: "硫酸環境下におけるコンクリートの劣化性状と内部強度分布に関する研究"コンクリート工学論文集. 15・1. 35-43 (2004)

青柳直树：“硫酸环境下混凝土的劣化特性和内部强度分布的研究”《混凝土工程杂志》15・1（2004）。

Alexandru Lechkun, 板橋洋房, 三浦尚: "Sulfuric acid attack on concrete at various temperatures"土木学会東北支部技術研究発表会(平成15年度)講演概要集. 598-599 (2004)

Alexandru Lechkun、Hirofusa Itabashi、Takashi Miura：“不同温度下的硫酸对混凝土的侵蚀”日本土木工程师学会东北分会技术研究会议摘要集（2003 年）598-599（2004 年）。

Naoki AOYAGI, Yusuke YOSHIDA, Syukou WATANABE, Takashi MIURA: "Study on the deterioration of concrete and internal evaluated strength distribution exposed to sulfuric acid environments"Concrete Research and Technology. Vol.15,No.1. 35-43 (2004)

Naoki AOYAGI、Yusuke YOSHIDA、Syukou WATANABE、Takashi MIURA：“硫酸环境下混凝土劣化及内部评估强度分布的研究”混凝土研究与技术。