This article presents an investigation on corrosion damage effects on the shear bearing capacity of reinforced concrete (RC) beams after a fire. Accelerated corrosion tests were conducted using four RC beams designed with corrosion crack widths ranging from 0.1 mm to 0.3 mm to simulate an aggressive corrosion-prone environment. One control beam (B1) did not undergo accelerated corrosion. The fire test was conducted separately on each beam for two hours to explore how the different widths of corrosive cracks affect heat propagation at elevated fire-induced temperatures. A residual capacity test determined the effects of corrosion on the beams’ residual shear strength after a fire. The experimental results showed that corrosion cracks accelerate the heat propagation in concrete during a fire; moreover, the post-fire residual shear strength for corroded RC beams slightly decreased with an increasing degree of corrosion on the stirrups. The authors also developed a corresponding simplified calculating method to determine residual shear strength, which showed shear design provisions that could improve some existing codes.

本文对火灾后钢筋混凝土 (RC) 梁的抗剪承载能力的腐蚀损伤影响进行了研究。加速腐蚀测试使用四个 RC 梁进行，设计的腐蚀裂纹宽度范围为 0.1 毫米到 0.3 毫米，以模拟腐蚀性易腐蚀环境。一根控制梁 (B1) 没有经历加速腐蚀。对每根梁分别进行了两个小时的火灾测试，以探索不同宽度的腐蚀裂纹如何影响火灾引起的温度升高时的热传播。残余承载力测试确定了腐蚀对火灾后梁的残余剪切强度的影响。试验结果表明，腐蚀裂纹加速了火灾过程中混凝土中的热量传播；而且，随着箍筋腐蚀程度的增加，腐蚀钢筋混凝土梁的火灾后残余剪切强度略有下降。作者还开发了相应的简化计算方法来确定残余剪切强度，该方法显示了可以改进一些现有规范的剪切设计规定。