The electric accelerated corrosion test and theoretical analysis method are applied to investigate the degradation regularity of the bearing capacity of reinforced concrete（RC）beams. The uncorroded or slightly corroded beams exhibit the typical failure mode of appropriate reinforcement beams

while severely corroded beams present the failure mode of less reinforcement beam.The ultimate bearing capacity

ductility and stiffness of RC beam decrease gradually. When the corrosion rate is less than 1%

the bonding strength is enhanced by the volume expansion of corrosion products.However

when the corrosion rate reaches 24%

the ultimate bearing capacity of severely corroded RC beams greatly decrease because of severe local corrosion and initiation and propagation of corrosive cracks.The degradation regularity of the bearing capacity of RC beams can be accurately simulated using the coordination coefficient method or standard method as the corrosion rate is less than 24%.