锈蚀钢筋混凝土梁的疲劳性能

对8根模拟锈蚀钢筋混凝土梁进行了高周疲劳试验，研究和探讨了模拟锈蚀钢筋混凝土梁的疲劳性能。结果表明，交变荷载作用下试件的斜裂纹出现并迅速发展成主裂缝；模拟锈蚀钢筋混凝土梁多在端部发生剪切疲劳破坏；试件的挠度发展、裂缝分布与破坏形态密切相关；随循环次数增加，锈蚀主筋的最大、最小应力不断增长，应力幅值基本不变；混凝土的最大、最小压应变快速增长，应变幅值平稳增长；试件的疲劳寿命具有较大的离散型；同等条件下，锈蚀钢筋混凝土梁的疲劳寿命往往比锈蚀钢筋的轴向拉伸疲劳寿命长。

Fatigue Behavior of Corroded Reinforced Concrete Beams

High-cycle fatigue tests were performed on 8 corroded reinforced concrete beams, the fatigue behavior of reinforced concrete beams with corroded main reinforcing steel bars were investigated. The test results indicate that the diagonal cracks of specimens emerge and develop quickly under the alternate loads, finally become the main cracks; most simulate corroded reinforced concrete beams appear shear fatigue failure near the end; the deflection development and crack distribution of specimens are closely related with failure models; with the increasing of cycle numbers, the maximum and minimal stresses of corrosion main reinforcement increase gradually, and the stress amplitudes change little; the maximum and minimal compressing strain of concrete develop quickly, and the strain amplitudes increase stably; the fatigue life of specimens has more discreteness; the fatigue life of the corroded reinforced concrete beams is longer than that of natural corrosion reinforcing steel bars subjected to axial tensile fatigue loads under the similar corrosion and stress conditions.