## 2 Materials and Methods
### Specimen Mixing, Casting and Curing  
Due to its high absorption capacity, the recycled aggregate was partially saturated with water. This reduced the amount of additional water that had to be added during mixing to compensate for the saturated surface dry condition of the moisture. All concrete constituents were conditioned at 20 \(\pm\) 2 \({}^{\circ}\)C. Mixing was carried out in a compulsory mixer with a capacity of 75 litres. Since the amount of concrete for each mix was 108 litres, two batches were made for each mix, first the batch of 48 litres and then the second batch of 60 litres. Care was taken to reduce the time between mixing the two batches to around 45 to 60 min.  
In the normal concrete mixes, the aggregates were first mixed with about half of the mixing water for two minutes. At the end of the two-minute standing time, the cement was added and mixed with the aggregate, followed by the addition of the remaining water mixed with superplasticizer. For SCC mixtures, aggregate and filler were mixed with about one-third of the water. After 30 s, cement or cement and fly ash were added, followed by the addition of the second third of the water. After two minutes of mixing, the remaining water, premixed with superplasticizer, was added and mixed for 1.5 min. Mixing was then interrupted for two minutes and continued for a further three minutes. For SCC mixtures, a slump flow test was carried out to check whether sufficient flowability of the mixture was achieved. An additional amount of superplasticizer was added to the first batch, if necessary, to achieve the desired slump or slump flow, and it was mixed for a further two minutes. In all cases, the second batch of mix was prepared with the same total amount of superplasticizer as the first batch, which was added premixed with water. Therefore, there is a difference in the type of superplasticizer dosage between the first and second batches.  
The concrete specimens made from the NC1 and NC2 mixes were compacted on a vibrating table, while no vibration was used for the specimens made from SCC. After casting, the specimens were stored at a temperature of 20 \(\pm\) 5 \({}^{\circ}\)C and covered with a plastic sheet. After 24 h, the specimens were demoulded. The specimens for the compressive strength test and [PERSON]'s modulus test were stored in the curing chamber at a relative  
\begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \multirow{2}{*}{**Component**} & \multicolumn{8}{c}{**Concrete Mixture**} \\ \cline{2-10}  & **NC 1** & **NC 2** & **SCC0** & **SCC10** & **SCC20** & **SCC30** & **SCC40** & **SCC50** & **SCC60** \\ \hline Cement (kg) & 400 & 400 & 400 & 400 & 400 & 200 & 400 & 400 & 200 \\ \hline Natural aggregate 0/4 mm (kg) & 930 & 930 & 970 & 970 & 970 & 970 & 970 & 970 & - \\ \hline Natural aggregate 4/8 mm (kg) & 267 & - & 310 & 310 & - & - & 310 & - & - \\ \hline Natural aggregate 8/16 mm (kg) & - & - & 320 & - & - & - & - & - & - \\ \hline Recycled aggregate 0/4 mm (kg) & - & - & - & - & - & - & - & - & 970 \\ \hline Recycled aggregate 4/8 mm (kg) & - & 267 & - & - & 310 & 310 & - & 310 & 310 \\ \hline Recycled aggregate 8/16 mm (kg) & 644 & 644 & - & 320 & 320 & 320 & 320 & 320 & 320 \\ \hline Water (I) & 200 & 200 & 200 & 200 & 200 & 200 & 160 & 160 & 160 \\ \hline Superplasticizer (kg) & 2.4 & 2.0 & 16.1 & 7.6 & 10.5 & 8.6 & 12.6 & 16.9 & 20.6 \\ \hline Filler (kg) & - & - & 200 & 200 & 200 & 200 & 200 & 200 & 200 \\ \hline Fly ash (kg) & - & - & - & - & - & 200 & - & - & 200 \\ \hline Water/cement ratio & 0.5 & 0.5 & 0.5 & 0.5 & 0.5 & 0.5 & 0.4 & 0.4 & 0.4 \\ \hline Aggregate/paste ratio (by volume) & 2.21 & 2.28 & 1.75 & 1.86 & 1.91 & 1.75 & 2.08 & 2.13 & 2.09 \\ \hline \end{tabular}
\end{table}
Table 3: Concrete mix composition quantities per 1 m\({}^{3}\).  
humidity of >95% and a temperature of 20 \(\pm\) 2 \({}^{\circ}\)C. The specimens for the shrinkage and creep tests were prepared for testing and transported to the test room where the relative humidity was kept at 60 \(\pm\) 5%.