加速锈蚀与自然锈蚀钢筋混凝土梁受力性能比较分析

对自然锈蚀与外加电流加速锈蚀2种条件下的锈蚀钢筋及锈蚀钢筋混凝土梁进行了对比试验研究.从钢筋锈蚀特征、锈后力学性能、锈胀形态、锈蚀梁受弯性能以及破坏形态等方面进行了比较分析,并从电化学机理对2种锈蚀方式做出了阐释.结果证明,外加电流加速锈蚀法可以较好地表现锈蚀引起的结构性能劣化趋势,但由于锈蚀机理的不同,它与自然锈蚀在各个方面存在显著差异,在同等质量锈蚀率下自然锈蚀钢筋混凝土梁的极限变形能力退化更为明显,加速锈蚀钢筋混凝土梁的刚度退化更为明显.

Comparative study on structural performance of reinforced concrete beams subjected to natural corrosion and accelerated corrosion

Corroded steel bars and corroded reinforced concrete beams derived from natural environment and impressed current induced corrosion were tested. The corrosion characteristic, mechanical performance of rebar, expansive cracking of concrete cover, structural behavior and failure modes of corroded beams from these two corrosion patterns were compared. It is shown that accelerated corrosion using impressed current is an effective way to study the deterioration of structural performance caused by rebar corrosion. However, due to the difference in mechanism, obvious differences can be found in the test results from both corrosion processes. The degradation of ultimate deforming ability of R/C beams due to natural corrosion is more serious and the degradation of the stiffness of R/C beams due to accelerated corrosion is more serious under the same weight loss ratio of corroded rebars.