为研究不同类型钢筋锈蚀对钢筋混凝土梁抗弯性能的影响,制作了9根螺纹钢筋和9根光圆钢筋混凝土矩形梁,并对其进行电化学快速锈蚀试验,研究不同锈蚀率下2种类型钢筋混凝土梁的荷载-挠度曲线、承载力退化、裂缝发展及破坏模式。考虑锈蚀钢筋与混凝土间的粘结滑移,采用有限元软件 MARC,对锈蚀钢筋混凝土梁的破坏过程进行了模拟,并对粘结性退化系数的影响进行了敏感性分析。研究结果表明：锈蚀对光圆钢筋梁承载力退化的影响大于它对变形钢筋梁的；开裂后钢筋与混凝土应变逐步趋于不协调；对于梁端锚固较好的梁,粘结力的变化对梁极限抗弯承载能力的影响不大,但对梁的刚度影响较大；随着锈蚀率的增加,梁的破坏形式逐步由延性破坏转为脆性破坏。本研究的有限元计算值与试验值较为吻合,可为建立锈蚀 RC梁承载力理论计算模型提供参考。%In order to study the impact of different types of reinforcement corrosion on the flexural performance of reinforced concrete beam,nine deformed and nine plain bar reinforced concrete rectangular beams were manufactured,respectively.An electricity ac-celerated corrosion test was used in the experimental process.The load-deflection curve, bearing capacity degradation,crack development and failure modes of two types of rein-forced concrete beams under different corrosion rates were discussed.Considering the bond-slip between the steel and the concrete,the failure process of corroded reinforced concrete beams was simulated by the finite element software MARC,and a sensitivity a-nalysis on the bond degradation coefficient was also analyzed.The results show that the corrosion has more significant effects on the strength degradation for the beam with plain bars than the beam with deformed steel bars.The strain of the steel and the con-crete tended to be uncoordinated after concrete cracking.For the beam with good anchor-age at the ends,the change in bond strength had little effects on the ultimate carrying capacity,but had significant effects on the stiffness.The failed type of beams gradually changed from ductile into brittle with the increase of corrosion levels.The calculated re-sults by the finite element method was consistent with the experimental observations, which can provide a reference for establishing a theoretical model in future studies.
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