碱激发矿渣液相环境中钢筋钝化膜形成及破坏规律

硅酸盐通报 ›› 2024, Vol. 43 ›› Issue (10): 3607-3614.

碱激发矿渣液相环境中钢筋钝化膜形成及破坏规律

万小梅^1,2, 王博世¹, 孙忠涛¹, 张东方³

1.青岛理工大学土木工程学院,青岛 266520;
2.青岛理工大学蓝色经济区工程建设与安全山东省协同创新中心,青岛 266520;
3.青岛海信房地产股份有限公司,青岛 266071

收稿日期:2024-04-10 修订日期:2024-05-31 出版日期:2024-10-15 发布日期:2024-10-16
作者简介:万小梅(1974—),女,博士,教授。主要从事高性能混凝土及混凝土耐久性、新型胶凝材料混凝土、固废资源化利用等方面的研究。E-mail:wanxiaomei1211@hotmail.com
基金资助:
国家自然科学基金(51878365);山东省自然科学基金(ZR2023ME030)

Formation and Failure Law of Rebar Passivation Film in Liquid Phase Environment of Alkali-Activated Slag

WAN Xiaomei^1,2, WANG Boshi¹, SUN Zhongtao¹, ZHANG Dongfang³

1. School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China;
2. Cooperative Innovation Center of Engineering Construction and Safety in Shandong Blue Economic Zone, Qingdao University of Technology, Qingdao 266520, China;
3. Qingdao Hisense Real Estate Co., Ltd., Qingdao 266071, China

Received:2024-04-10 Revised:2024-05-31 Published:2024-10-15 Online:2024-10-16

摘要/Abstract

摘要： 为探寻碱激发矿渣(AAS)液相环境中钢筋钝化膜的形成和破坏机制,本文制备了不同配合比的AAS胶凝材料体系,研究了AAS真实孔溶液pH值在不同激发剂种类、碱当量、水玻璃模数、粉煤灰掺量、养护时间等因素下的经时演变规律,并对模拟孔溶液中钢筋钝化膜的生成时间、组成成分、厚度和钝化膜破坏时的临界氯离子浓度进行了经时追踪检测及分析。结果表明,AAS真实孔溶液的pH值随养护时间的增加而下降,各样品28 d时的pH值均保持在12.8以上。模拟孔溶液中pH值的增加缩短了钢筋钝化膜的形成时间,增加了钝化膜厚度,并提高了其抗氯离子侵蚀能力。AAS真实孔溶液较高的pH值可为钢筋钝化膜的稳定存在提供更有利的液相环境,从而提高钢筋混凝土结构的长期服役性能。

关键词: 碱激发矿渣, 孔溶液, pH值, 钢筋钝化膜, 钢筋锈蚀, 激发剂

Abstract: To explore formation and failure mechanism of rebar passivation film in the liquid-phase environment of alkali-activated slag (AAS) system, AAS cementitious material systems with different mixing designs were prepared. The time-dependent evolution of the pH value of AAS real pore solution was studied in various factors such as different types of activator, alkali equivalent, water-glass modulus, fly ash addition, and curing time. In addition, the generation time, composition, thickness, and critical chloride threshold of rebar passivation film in simulated pore solution were monitored and analyzed over time. The results show that the pH value of AAS real pore solution decreases with the increase of curing time, with pH values of all samples remaining above 12.8 at 28 d. The increase in pH value in the simulated pore solution reduces the formation time of rebar passivation film, increases its thickness, and enhances its resistance to chloride ion erosion. The characteristic of AAS real pore solution having a higher pH value can provide a more favorable liquid phase environment for the stable existence of rebar passivation film, thereby improving the long-term performance of reinforced concrete structures.

Key words: alkali-activated slag, pore solution, pH value, rebar passivation film, rebar corrosion, activator

中图分类号:

TU528.59

万小梅, 王博世, 孙忠涛, 张东方. 碱激发矿渣液相环境中钢筋钝化膜形成及破坏规律[J]. 硅酸盐通报, 2024, 43(10): 3607-3614.

WAN Xiaomei, WANG Boshi, SUN Zhongtao, ZHANG Dongfang. Formation and Failure Law of Rebar Passivation Film in Liquid Phase Environment of Alkali-Activated Slag[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2024, 43(10): 3607-3614.

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