Sustainable Construction Materials and Technologies, cilt.7, sa.2, ss.108-118, 2022 (Scopus)
The aim of the study is to optimize the aggregate gradation curve (AGC) 
for recycled aggregate concrete (RAC). Accordingly, TS 802 aggregate 
gradation curves such as A16, B16 and C16 and, also two proposed AGCs 
such as G1 and G2 are examined in the experiments. Hence, in total, 10 
mixes are designed in consideration of A16, B16, C16, G1 and G2. The 
physical (density and water absorption) and the mechanical (compressive 
strength) properties are determined conducting the standard tests at the
 age of 28th days after a standard 22±2oC water curing. Also, a 
criterion weighting method such as Entropy Method is used in the 
evaluation of the properties of concretes and the weights of the 
properties of concretes are determined. Then, TOPSIS is used to find the
 best concrete in consideration of the design parameters and test 
results for the selection of the optimum AGC. As a result, the influence
 of AGC on the properties of natural aggregate concretes (NACs) and RACs
 are unsimilar and while A16 results in a denser NAC with higher 
compressive strength, C16 can be offered to decrease the open pore 
content of RAC in terms of water absorption leading a durable concrete 
with a higher compressive strength. Besides, the results of Entropy 
Method present interesting findings, and the coarse aggregate ratio in 
the mix is found as the most effective parameters among the investigated
 design parameters. However, the best AGCs are found as A16 for NAC and 
G2 for RAC according to TOPSIS results. It is concluded that further 
investigations are required.