不同应力比往复荷载作用后锈蚀钢筋混凝土梁承载力分析

Analysis on load carrying capacity of the corroded reinforced concrete beam after cyclic loading with different stress ratio

研究锈蚀钢筋混凝土构件在不同应力比往复荷载作用后的实际承载力变化规律对于进一步研究钢筋锈蚀与往复荷载耦合破坏作用及确保结构安全使用方面具有重要意义。本文运用ABAQUS有限元软件,通过修改钢筋截面面积及钢筋强度等参数来模拟往复荷载应力比及钢筋锈蚀的影响,对不同应力比往复荷载作用后锈蚀钢筋混凝土梁的承载力进行静力非线性数值模拟分析,得出以下结论:往复荷载的应力比会显著影响钢筋混凝土简支梁的屈服荷载,且应力比对屈服荷载的影响程度要大于钢筋锈蚀率对屈服荷载的影响;当往复荷载的应力比较小时,应力比的变化对钢筋混凝土梁的极限挠度影响显著,当应力比较大时,应力比的变化对极限挠度的影响变小,而且,应力比与锈蚀率对极限挠度的影响程度基本一致;锈蚀率的增加对屈服荷载的影响程度不随应力比的变化而变化,但锈蚀率的变化对极限挠度的影响程度与应力比相关。

It is significant to research the change of real load carrying capacity of the corroded reinforced concrete members after cyclic loading with different stress ratios for research on the coupling effect between steel corrosion and cyclic loading and structural safety.ABAQUS software was adopted to numerically simulate the influence of the stress ratio of cyclic loading and steel corrosion by modifying section area and strength of the steel bars. Non- linear static analysis of the corroded reinforced concrete simply- supported beam with different corrosion rates under cyclic loading with different stress ratios were carried out. From the results,some conclusions can be given. The stress ratio of cyclic loading obviously affects the yield load of corroded simply supported reinforced concrete beam,and the effect extent of stress ratio to the yield load is higher than that of steel corrosion rate. When the stress ratio of cyclic loading is small,it obviously affects the ultimate deflection of reinforced concrete beam. When the stress ratio becomes larger,the effect of stress ratio on the ultimate deflection becomes weak. Also,the effect extent of stress ratio on the ultimate deflection is identical to steel corrosion rate.The effect of corrosion rate＇s increasing on the yield load does not change as the stress ratio varies. But,the effect extent of variations of corrosion rate on the ultimate deflection is related to the stress ratio.