锈蚀钢筋混凝土梁疲劳后的刚度分析与计算

Analysis and Calculation of Stiffness for Corroded Reinforced Concrete Beam after Fatigue

对锈蚀钢筋混凝土梁进行了在疲劳荷载作用下的试验研究,结果表明随着钢筋的锈蚀率和疲劳荷载增加,其截面刚度呈现下降趋势。同时进行了锈蚀钢筋混凝土梁疲劳后的刚度分析和计算。腐蚀试验采用电化学加速试验的方法,疲劳试验采用等幅疲劳加载试验。考虑疲劳荷载和钢筋锈蚀对构件粘结退化的双重影响,导致构件截面的刚度降低的因素后,基于试验研究结果,给出了疲劳荷载作用下的刚度降低系数θf,用以修正疲劳后锈蚀钢筋混凝土梁的截面弯曲刚度计算公式。研究结果可为混凝土结构的耐久性评估提供科学依据。

The corroded reinforced concrete beams under the fatigue loads were studied and we concluded that the section stiffness for the corroded reinforced concrete beams decreased with the increase of the steel corrosion rate and the fatigue load.At the same time,the stiffness of the corroded reinforced beams after fatigue was analyzed and calculated.The electrochemical acceleration test was used in test of beam corrosion and the constant-amplitude fatigue load test was adopted in fatigue test.The stiffness reduction coefficient θf under the effect of fatigue load was given based on the test results and after studying the coupling effects of the fatigue load and steel corrosion on the components bond degradation,which lead to stiffness reduction of the component section and the stiffness reduction coefficient θf was used to correct the bending stiffness calculation formula for the corroded reinforced concrete beam section after the fatigue.The research results can provide a scientific basis for the durability evaluation of the concrete structures.