EFFECT OF REINFORCEMENT AND CORROSION ON DAMPING CAPACITY OF CONCRETE MEMBERS

Reinforcement and corrosion have a significant impact on the dynamic parameters of reinforcement concrete (RC) members. Taking the longitudinal reinforcement ratio, steel surface shape, stirrup spacing, and corrosion ratio as influencing factors, a three-point bending dynamic test was conducted to study the influence of aforementioned factors on the loss modulus and tangent of concrete under small bending deformation. The relationship between rigidity degeneration, damping evolution and corrosion ratio were also analyzed. The test results show that the loss modulus and tangent first increase with the reinforcement ratio and then tend to decrease. Their values reach a peak value around a 1% reinforcement ratio. On the contrary, loss modulus and tangent first decrease and then increase with a corrosion ratio. They get the minimum values around a 0.4% corrosion ratio. With regards to the stirrup spacing, loss modulus and tangent decrease monotonously with an increment in spacing. The crescent-ribbed, round, and rectangular bar used in concrete, has a decreasing enhancing effect for loss modulus and tangent. In addition, the corrosion ratio has an obvious impact on damping increment than rigidity degeneration. It indicates that the damping parameters of a corroded RC member are better to evaluate their damage level.