Damping Properties of Recycled Aggregate Concrete and Simply-Supported Recycled Aggregate Concrete Slabs

Abstract:

The effects of recycled coarse aggregate(RCA) replacement percentage, polymer damping material, boundary conditions and damage level on the damping properties of recycled aggregate concrete (RAC) material and slabs were studied by using suspension, cantilever, and simply-supported tests. On the material level, the test results show that the damping ratio of RAC increases with the increase of the replacement percentage of RCA. The damping ratio of RAC with 100% replacement of the RCA is increased by 30% compared with the referenced natural aggregate concrete. Adding rubber particles can significantly improve the damping ratio of RAC in the elastic stage. Adding polypropylene fiber has no remarkable effect on the damping ratio of RAC in the elastic stage. On recycled aggregate concrete slabs, it is found that the damping ratios of recycled concrete slabs increase first and then decrease with the increase of the damage degree. The relationship between the cracking behaviors and the change in damping ratios are identified by observing the development of cracks. It shows that the damping ratio of RAC slabs is related to the crack behaviors, thus the interface friction damping caused by the crack is an important factor affecting the damping ratio of RAC slabs.