Study On Flexural Behavior Of Corroded Reinforced Concrete Beams

Corrosion of steel bar in reinforced concrete beams leads to reduction of the cross-section of the steel bar and change of steel mechanical properties, longitudinal cracking of concrete cover and change of bond strength between steel bar and concrete. These mentioned factors greatly influence the mechanical behavior and the load carrying capacity of reinforced concrete beams. On the base of finite element software ANSYS, flexural behavior of corroded reinforced concrete beams are studied. The main research works and the results are as follows:Pull test of corroded steel bars was simulated. Effects of corrosion pits on the stress distribution were studied. Relationship between the nominal yield strength and the maximum corrosion ratio was analyzed. The nominal yield strength of corroded steel bars was discussed with respect to the width and depth and obliquity of the pit.It is studied that the nonlinear finite element model was simulated to analyze corroded reinforced concrete member. 13 corroded reinforced beams were collected and analyzed. Paralleling calculating result with the test proves the reliability of this model. By the aid of finite procedure, flexural behavior of symmetrical corroded reinforced concrete beams and partial ones were studied with respect to different corrosion ratio. The influence of corrosion ratio on the stiffness, the slip between the steel bar and the concrete, the stress of longitudinal steel bar, the appearance of crack and the failure mechanism were studied.Different kinds of calculation method of flexural capacity of corroded reinforced concrete beams were discussed. 6 corroded reinforced concrete beams and other 2 undamaged ones were analyzed on the assumption that they were bonded beams and unbonded ones. An applicable calculation method of flexural capacity of corroded reinforced concrete beams was presented. Finally, a method of calculating flexural stiffness of corroded reinforced concrete beams was given by modifying the expressions in actual criterions.