Effect of strength of parent concrete on the mechanical properties of recycled aggregate concrete

The effect of quality of original concrete, from which coarse recycled concrete aggregate particles were derived, on mechanical properties of three grades of recycled aggregate concrete (RAC) has been investigated for the following two weight replacement levels of natural coarse aggregates (NCA) with the recycled aggregates: 50% and 100%. The original concrete samples made with natural coarse aggregates were designed for 28-day nominal cube crushing strengths of 20 MPa, 40 MPa and 60 MPa. The results indicated that the grade of original concrete did not have a significant effect on the mechanical properties viz. compressive strength, splitting tensile strength and flexural strength of the three grades of RCA concretes of this investigation. All the aforesaid properties were inferior to those of the control concrete made only with NCA. However, in case of the high-strength parent concrete, the mechanical properties of the resultant RAC were superior as compared to RAC made with normal and medium strength parent concrete. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

The quality of original concrete does not have a significant effect on the mechanical properties of recycled aggregate concrete. However, recycled aggregate concrete made from high-strength parent concrete exhibits superior mechanical properties compared to those made from normal and medium strength parent concrete.