*2.2. Rheological, Thermal and Mechanical Characterization*

The flow-test allowed the evaluation of the rheological properties of the fresh conglomerates [51]. An ISOMET 2104, Applied Precision Ltd (Bratislava, Slovakia), was used to determine the thermal conductivity (λ) and the thermal diffusivity (α) of the specimens by production of a constant thermal flow by a heating probe applied on the sample surface. The temperature was recorded over time and λ and α were obtained after evaluation of the experimental temperature compared with the solution of the heat conduction equation [52]. The flexural and compression tests were carried out by the use of a MATEST device (Milan, Italy). Flexural tests were carried out on six prisms (40 mm × 40 mm × 160 mm) by applying a load with a 50 ± 10 N/s rate, while compression strengths were obtained on the resulting semi-prisms by applying a load with a 2400 ± 200 N/s rate [46].

#### *2.3. Measurements of the Contact Angle and of the Water Absorption*

In the present research, an investigation on the side surface and on the inner surface of the cement conglomerates was carried out by contact angle measurements. After deposition of at least fifteen drops (5 μL) of water onto the surface of each specimen, it was shown that the behavior of three representative points (point 1, 2, and 3) summarized the behavior of all the drops. A Premier series dyno-lite (Taiwan) portable microscope and background cold lighting was used to study the time evolution of the drop, with a rate ranging of 30 frames per second. In the case of non- static drop, determined by water absorption, the image sequences were analyzed by Image J software (version 1.8.0, National Institute of Health, Bethesda, MD, USA) in order to measure the variation of the contact angle and of the drop height.
