为了给锈蚀RC结构性能退化评估提供参考,制作了12片RC梁和5个粘结试件,通电加速腐蚀RC梁和粘结试件,考虑不同锈蚀率和保护层厚度对锈蚀梁性能退化的影响,建立可以考虑粘结滑移的锈蚀梁性能退化的有限元模型,研究锈蚀梁的抗弯性能退化机理。结果表明:保护层厚度为25mm时,梁挠度的增加速率随着锈蚀率的增大而增大,而当保护层厚度分别达到30mm和35mm时,锈蚀梁与未锈蚀梁的挠度随荷载增加的速率差别不大;锈蚀破坏了结构的整体性、刚度以及钢筋与混凝土的粘结作用,是结构性能退化的主要原因;考虑粘结滑移的有限元数值模拟结果与试验结果较为吻合。
In order to provide references for performance degradation assessment of corroded RC structures,12 beams and 5bonding specimens were manufactured to consider the influences of different corrosion rates and the thicknesses of protective layers on the flexural performance degradation of corroded RC beam by electricity accelerated corrosion,and a finite element model considering bond-slip was made to investigate the flexural performance degradation mechanism of corroded beams.The results show that deflection increasing rate of corroded RC beam increases with the increase of corrosion rate when thickness of a protective layer is 25 mm.However,when the thicknesses of protective layers increase to be 30 mm and 35 mm respectively,the increasing rates of deflection of non-corroded and corroded beams are very close.Corrosion of reinforcing bar is a major cause of structural performance degradation,which damages integrity,stiffness and bond-slip between steel and concrete.The calculated value of the finite element numerical simulation considering bond-slip agrees well with the experimental value.