Shear transfer across a crack in recycled aggregate concrete

In this paper, 32 pre-cracked recycled aggregate concrete (RAC) push-off specimens made from 10 mix designs were tested to study the shear transfer performance across cracks. The effects of recycled coarse aggregate (RCA) replacement ratio, the water to cement ratio, the concrete strength, and the lateral constraint on the shear transfer performance were carefully investigated. The experimental results and data analysis show that the shear transfer mechanism and process across cracks in RAC is largely the same as that in natural aggregate concrete (NAC). Both the lateral constraint and the concrete compressive strength positively affect the shear transfer strength of the RAC. However, the RCA replacement ratio has adverse effects on the shear transfer strength when it is over 30%. It is also found that the design equations for NAC in ACI and PCI codes may be used to predict the shear transfer strength of RAC.