*2.3. Penetrometer Tests*

In order to determine the initial and final setting of the samples, penetration resistance tests were carried out on the same batch of mortar and concrete samples, according to ASTM C403 [4]. For concrete samples, sieving is needed, and the sieved mortar was obtained by wet-sieving the selected portion of concrete through a 4.75-mm sieve and onto a non-absorptive surface. In the penetration resistance tests, mortar samples were penetrated using standard needles, and the resistance value was obtained at regular time intervals. Then a plot of penetration resistance versus time was used to determine the times of initial and final setting. The initial and final times of setting correspond to penetration resistance values of 3.5 MPa and 27.6 MPa, respectively. The setting times of all the mixtures are also listed in Table 1.
