Nonlinear Analysis Of The Corroded Reinforcement Concrete Thin-box Beams

The thin-walled box girder has been used widely in civil engineering due to its lightweight and high-rigidness. The corrosion of reinforcing steel bars is an important factor that influences the durability of RC concrete structures. As a result of corrosion, the cross section of bars will be whittled down, the mechanical properties and the bond strength between bars and concrete will be changed, the concrete covers will crack. These mentioned above greatly influence the load carrying capacity of the corroded reinforcement concrete thin-box beams. In order to evaluated the bearing capacity of RC concrete members after corrosion, a mathematical model for corrosion penetration of bars under the plane section assumption was established based on electrochemical principles. For compatibility with the code for design of concrete structures(GB 50010-2002), a mechanical model about corroded reinforcement concrete thin-box beams was established, the corrosion penetration of bars and the load carrying capacity of beams were discussed, and then some formulas were deduced. The developing regularity of cracking, deformation and load carrying capacity about corroded reinforcement concrete thin-box beams were obtained by nonlinear finite element analysis using ANSYS, which a versatile FEM analysis software. The theoretical results were compared with the finite element analysis to proved the validity and the reasonability of simple theoretical models and the finite element models.At last, this paper made a summary about FEM and theory analysis of thin-box beam, and some suggestions for further study were put forward.