锈蚀钢筋混凝土双筋矩形梁抗弯承载力分析

Analysis of the Flexual Bearing Capacity of Corroded Reinforced Concrete Beams with Double Reinforced Rectangular Section

钢筋锈蚀是钢筋混凝土桥梁的主要病害之一。在锈蚀钢筋混凝土双筋矩形截面梁中,钢筋锈蚀易造成结构性能退化,并引起钢筋和混凝土相对滑移,导致结构的承载力降低,受拉区的钢筋与混凝土变形不协调。通过构造新的几何条件,推导了锈蚀钢筋混凝土双筋矩形梁正截面极限抗弯承载力计算公式。对室内快速锈蚀双筋矩形梁进行正截面抗弯承载力实验,结果表明推导的锈后双筋矩形梁正截面抗弯承载力公式的计算值与实验值吻合较好。上述工作为进一步进行工程实践奠定了基础。

Corrosion of steel bar is one of the main disease forms of reinforced concrete beams. In a corroded reinforced concrete beam with double reinforced rectangular section, the structure performance is degraded, the amount of the relative bond-slip between concrete and reinforcement increases and the bearing capacity is affected by steel bar corrosion. By constructing a new geometrical condition, formulas of ultimate bending capacity of normal section for corroded reinforced concrete beam with double reinforced rectangular section were derived when the steel deformation is not accordance with the concrete in the tensile region. Combined with the flexual bearing capacity experiments of beam with double reinforced rectangular section in lab by rapid corrosion, results show that the computational value of calculation formula is in good agreement with the experimental value. Above analysis may lay a foundation for tfurther application in engineering practice.