Hysteretic energy and damping variation of recycled aggregate concrete with different cyclic compression loading levels

Abstract

This paper presents an investigation on the effects of recycled coarse aggregate (RCA) replacement ratio and recycled rubber particle (RRP) size on the hysteretic energy and damping variation of recycled aggregate concrete (RAC) under various cyclic compression loadings. The hysteretic energy and damping of RAC v. s. The same stress amplitude and strain amplitude were compared and analyzed, and the mechanism of hysteretic energy and damping variation of RAC were discussed. The results show that the hysteretic energy of RAC increases with increasing RCA replacement ratio and RRP size under the same stress amplitude, while an opposite phenomenon is observed under the same strain amplitude. The incorporated RRPs and RCAs improve the hysteretic energy and damping of RAC in the elastic stage under the same stress amplitude. The hysteretic energy and damping variation of RAC are closely related to the damage evolution and dynamic modulus degradation with increasing levels of applied loading. The hysteretic energy follows a power function of the applied stress amplitude or strain amplitude, and the energy dissipation within the RAC defects is the main damping mechanism of RAC. The damping variation of RAC under the same stress amplitude is mainly affected by the hysteretic energy as the stress evolves; however, the damping variation under the same strain amplitude is primarily impacted by the dynamic modulus as the strain evolves.