Rehman Fazal-Ur, Cashell Katherine A, Anguilano Lorna
Department of Civil and Environmental Engineering, College of Engineering, Design and Physical Science, Brunel University London, Kingston Lane, London UB8 3PH, UK.
Experimental Techniques Centre, College of Engineering, Design and Physical Science, Brunel University London, Kingston Lane, London UB8 3PH, UK.
Materials (Basel). 2022 Feb 19;15(4):1564. doi: 10.3390/ma15041564.
This paper is concerned with the behaviour of stainless steel reinforcing bar following exposure to elevated temperatures from a fire, followed by subsequent cooling. Stainless steel-reinforced concrete is an increasingly popular solution for structural applications which require corrosion resistance, excellent mechanical properties, and long life cycles with little maintenance. In addition, although stainless steel reinforcement has a higher initial cost compared with traditional carbon steel bars, the overall life cycle costs are likely to be quite similar, owing to the lack of maintenance required for stainless steel materials. There is no information available in the literature on the post-fire properties of austenitic stainless steel reinforcement, although these data are essential for any engineer who wishes to study the structural integrity of a reinforced concrete component or system following a fire. Accordingly, this paper presents a detailed discussion and analysis from the results of a series of laboratory experiments on three grades of austenitic stainless steel reinforcement following various levels of temperature exposure and also different cooling rates. Both the mechanical and metallurgical properties are examined, and the behaviour is compared to that of B500B carbon steel reinforcement. It is shown that the stainless steel bars retained their mechanical properties under the majority of the scenarios examined and to a greater degree than traditional materials. This is important for the rehabilitation and salvage of existing reinforced concrete structures following a fire and also to avoid unnecessary demolition and replacement.
本文关注不锈钢钢筋在经历火灾高温后随后冷却的行为。不锈钢钢筋混凝土对于需要耐腐蚀、具备优异机械性能且维护需求少、使用寿命长的结构应用而言，是一种越来越受欢迎的解决方案。此外，尽管不锈钢钢筋相较于传统碳钢钢筋初始成本更高，但由于不锈钢材料所需维护较少，其总体生命周期成本可能相当相近。文献中没有关于奥氏体不锈钢钢筋火灾后性能的信息，尽管这些数据对于任何想要研究火灾后钢筋混凝土构件或系统结构完整性的工程师来说至关重要。因此，本文基于对三种等级的奥氏体不锈钢钢筋在不同温度暴露水平及不同冷却速率下进行的一系列实验室实验结果，展开了详细的讨论与分析。对其机械性能和冶金性能均进行了检测，并将其性能与B500B碳钢钢筋的性能进行了比较。结果表明，在所研究的大多数情况下，不锈钢钢筋都能保持其机械性能，且程度优于传统材料。这对于火灾后既有钢筋混凝土结构的修复和抢救非常重要，同时也有助于避免不必要的拆除和更换。
