主筋锈蚀对钢筋混凝土梁承载特性的影响

Effects of main bars corrosion on the bearing behavior of reinforced concrete beams

基于适当的钢筋、混凝土本构关系以及锈蚀钢筋和混凝土的黏结滑移模型,建立有限元模型,对5根不同主筋锈蚀率的钢筋混凝土梁进行承载特性分析。获得了梁中点处的荷载-挠度关系,受力筋的应变分布以及钢筋与混凝土之间的滑移分布。研究结果表明:随着受力筋锈蚀率的增大,钢筋混凝土梁的极限承载力降低,延性下降,受力筋的最大拉应变和伸长量逐渐增加,钢筋和混凝土之间的滑移量也大幅增加。

Based on appropriate constitutive relationship of steel,concrete and bond-slip model between corroded steel and concrete,a finite element model was established and the bearing properties of 5 reinforced concrete beams were analyzed under different reinforcement corrosion rates. The load-deflection relationship of beam midpoint,strain distribution of steel bar and the slip distribution between steel and concrete were obtained. The results show that the ultimate bearing capacity and ductility of the corroded reinforced concrete beams degrade,while the maximum tension strain and total stretch of corroded steel bar increase gradually,and the slip between them enlarges sharply with the increment of steel corrosion rate.