Dependence of polymer concrete vibration characteristics on internal pipe and damper embedment.

A method to improve the damping characteristics of polymer concretes was investigated. A pipe structure was embedded in polymer concrete specimens. The frequency-dependent variations of the dynamic stiffness and the loss factors of the specimens were measured by the vibration test method to identify the damping enhancement from the embedded structure. The weight reduction effect of epoxy resin usage was compared after the pipe embedment. Impact dampers were applied to the pipe-embedded polymer concretes to improve their vibrational energy dissipation. The impact dampers were fabricated through the insertion of impact balls into the pipe structures. The dynamic properties of the impact-damper-embedded polymer concretes were obtained by vibration tests. The damping performance was investigated according to the gap size between the impact ball and the pipe. An analytic model was used to predict the vibrational behavior of the polymer concrete when the impact dampers were applied. Consequently, the effect on vibration damping was identified for different mass ratios and gaps to find optimal construction. [ABSTRACT FROM AUTHOR]