Tian Hongsong, Kong Yujiang, Liu Bin, Ouyang Bin, He Zhenfeng, Liao Leng
Guizhou Bridge Construction Group Co., Ltd., Guiyang 550001, China.
State Key Laboratory of Mountain Bridge and Tunnel Engineering, Chongqing Jiaotong University, Chongqing 400074, China.
Materials (Basel). 2024 Jul 11;17(14):3421. doi: 10.3390/ma17143421.
The corrosion damage of rebars is a leading cause of structural failure in reinforced concrete structures. Timely detection and evaluation of corrosion damage are crucial for ensuring structural safety. The self-magnetic flux leakage (SMFL) technology is often used due to its unique advantages in detecting corrosion damage of rebars. However, challenges persist in theoretically characterizing corrosion damage and exploring influencing factors. Therefore, the magnetic dipole theory model coupled with multiple-shaped defects is proposed and the influence of corrosion expansion force on the detection of corrosion damage is analyzed. The results show that the standard deviation of the magnetic field intensity induced by corrosion varied by up to 833%, while that induced by corrosion expansion force did not exceed 10%. So the changes in the SMFL field induced by corrosion damage play the dominant role and the influence of corrosion expansion force can be ignored. In addition, corrosion damage experiments on reinforced concrete based on the SMFL technology were conducted. The results indicate that the SFML curves of rebars change monotonically with the increasing corrosion degree. Significant variations in the curves correspond well with the locations of severe corrosion on the rebars. There is a positive relationship between the proposed magnetic parameters and the corrosion degree of the rebars. Furthermore, a corrosion damage evaluation model considering multiple parameters is developed to predict the corrosion degree of rebars. The prediction results demonstrate high accuracy, with an average absolute error of only 8.33%, which is within 10%.
钢筋的腐蚀损伤是钢筋混凝土结构发生结构破坏的主要原因。及时检测和评估腐蚀损伤对于确保结构安全至关重要。自漏磁通（SMFL）技术因其在检测钢筋腐蚀损伤方面的独特优势而经常被使用。然而，在从理论上表征腐蚀损伤和探索影响因素方面仍然存在挑战。因此，提出了结合多种形状缺陷的磁偶极理论模型，并分析了腐蚀膨胀力对腐蚀损伤检测的影响。结果表明，由腐蚀引起的磁场强度标准差变化高达833%，而由腐蚀膨胀力引起的磁场强度标准差变化不超过10%。因此，腐蚀损伤引起的SMFL场变化起主导作用，腐蚀膨胀力的影响可以忽略不计。此外，基于SMFL技术对钢筋混凝土进行了腐蚀损伤试验。结果表明，钢筋的SFML曲线随着腐蚀程度的增加而单调变化。曲线的显著变化与钢筋上严重腐蚀的位置吻合良好。所提出的磁参数与钢筋的腐蚀程度之间存在正相关关系。此外，建立了一个考虑多个参数的腐蚀损伤评估模型来预测钢筋的腐蚀程度。预测结果显示出很高的准确性，平均绝对误差仅为8.33%，在10%以内。
