Dual-functional graphene-modified fibre reinforced cementitious matrix (FRCM) for simultaneous corrosion protection and structural strengthening

双功能石墨烯改性纤维增强水泥基体 (FRCM)，可同时实现腐蚀防护和结构加固

• 批准号: EP/T021748/1
• 负责人: Meini Su
• 金额: $ 43.28万
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FT021748%2F1
• 关键词: Dual; functional; graphene; modified; fibre

The corrosion of embedded steel rebar in reinforced concrete (RC) structures, which are the backbone of every nation's infrastructure, is a major issue. Interventions relating to the corrosion of RC structures are estimated to amount to about 35% of the total volume of all work in the global building sector. Reinforcement corrosion is induced via mobile chloride ions or other structurally harmful contaminates within the reinforced concrete, which happens due to a variety of reasons such as marine environment, de-icing salt in winter seasons, chloride content in concrete mixing and the use of sea sand, etc. With reinforcement corrosion, the load-bearing resistances of RC structures are reduced, with severe potential safety issues and also immense economic loss.A new intervention method, ICCP-SS (impressed current cathodic protection and structural strengthening), has recently been proposed. ICCP-SS combines the merits of impressed current cathodic protection (ICCP) and structural strengthening (SS) technologies, but uses one dual-functional material - carbon fibre reinforced cementitious matrix (C-FRCM). In this dual functional material, the carbon fibre (CF) mesh serves as the anode for ICCP and also the strengthening material for SS, while the cementitious matrix is the conductor for ICCP and the bonding material for SS. Previous studies have demonstrated effectiveness of the ICCP-SS technology for RC members. However, it has been found that prolonged ICCP would cause calcium leaching in the cementitious matrix at the anode interface, leading to drastic loss of mechanical properties and significant increase of electrical resistance of the bond between the cementitious matrix and CF mesh. Reducing calcium leaching to a level that does not adversely affect structural resistance is possible by increasing the compactness and the electrical conductivity of the cementitious matrix to achieve a more uniform electrical resistive field in the anode interface; introducing a tiny amount of graphene into the cementitious matrix has the potential to do so. The key to solving the problem is to prevent (or significantly slow down) the breakdown of C-S-H gel (i.e. loss of calcium) at anode interface under the same ICCP current density and duration. The remarkable properties of graphene make it a potentially ideal solution to this problem by producing a more uniform electrical field and more compact microstructures of the cementitious matrix. This project aims to solve two issues: to quantify the bond mechanical behaviour (for SS) and the electrical resistance at the CF/cementitious matrix interface (for ICCP) due to leaching, and to investigate means of reducing leaching. In summary, the ICCP-SS intervention method has vast potential in prolonging life of RC structures and introducing a small amount of graphene flakes in the dual-functional cementitious matrix has a number of beneficial synergistic effects to help realise the full potential of ICCP-SS.

钢筋混凝土结构是各国基础设施的重要组成部分，其内部钢筋的腐蚀是一个重要的问题。据估计，与钢筋混凝土结构腐蚀有关的干预措施约占全球建筑业所有工作总量的35%。钢筋腐蚀是通过钢筋混凝土中移动的氯离子或其他结构有害污染物引起的，其发生的原因是多种多样的，如海洋环境、冬季除冰盐、混凝土搅拌中的氯离子含量以及海砂的使用等。钢筋腐蚀会降低钢筋混凝土结构的承载力，近年来提出了一种新的干预方法--外加电流阴极保护和结构加固（ICCP-SS）。ICCP-SS结合了外加电流阴极保护（ICCP）和结构加固（SS）技术的优点，但使用一种双功能材料-碳纤维增强水泥基（C-FRCM）。在这种双功能材料中，碳纤维（CF）网作为ICCP的阳极，也是SS的增强材料，而水泥基基质是ICCP的导体和SS的粘合材料。先前的研究已经证明了ICCP-SS技术对RC成员的有效性。然而，已经发现，长时间的ICCP将导致阳极界面处的水泥基基质中的钙浸出，导致水泥基基质和CF网之间的粘结的机械性能的急剧损失和电阻的显著增加。通过增加水泥基质的致密性和电导率以在阳极界面中实现更均匀的电阻场，可以将钙浸出减少到不会不利地影响结构电阻的水平;将微量的石墨烯引入水泥基质中具有这样做的潜力。解决这一问题的关键是在相同的ICCP电流密度和持续时间下，防止（或显著减缓）阳极界面C-S-H凝胶的破坏（即钙的损失）。石墨烯的显着性能使其成为一个潜在的理想解决方案，通过产生更均匀的电场和更紧凑的微观结构的水泥基质。该项目旨在解决两个问题：量化由于沥滤导致的CF/水泥基基质界面处的粘结力学行为（对于SS）和电阻（对于ICCP），并研究减少沥滤的方法。总之，ICCP-SS干预方法在延长RC结构的寿命方面具有巨大的潜力，并且在双功能水泥基质中引入少量石墨烯薄片具有许多有益的协同效应，以帮助实现ICCP-SS的全部潜力。

项目成果

Effects of using aqueous graphene on behavior and mechanical performance of cement-based composites

• DOI: 10.1016/j.conbuildmat.2023.130466
• 发表时间: 2023-03
• 期刊: Construction and Building Materials
• 影响因子: 7.4
• 作者: Nguyen Tien Dung;M. Su;Michael S. Watson;Y. Wang

Current Perspectives and New Directions in Mechanics, Modelling and Design of Structural Systems

结构系统力学、建模和设计的当前观点和新方向

• DOI: 10.1201/9781003348443-204
• 发表时间: 2022
• 作者: Ridley I

Numerical Investigation of FRCM-Strengthened Corroded RC Beams under Cathodic Protection.

• DOI: 10.3390/ma15155334
• 发表时间: 2022-08-03
• 期刊: Materials (Basel, Switzerland)

Numerical and theoretical investigation on the constitutive model of graphene-enhanced FRCM composite

• DOI: 10.1016/j.jobe.2024.108734
• 发表时间: 2024-02-09
• 期刊: JOURNAL OF BUILDING ENGINEERING
• 影响因子: 6.4
• 作者: Zhu，Xiaoming;Su，Meini;Ueda，Tamon
• 通讯作者: Ueda，Tamon