## 3 Research Results and Discussion
The compressive strength of composition 6 of the specimens with the highest binder content is increased. To summarise the research results obtained, we can say that: although LWC structures are exposed to changes in humidity and freezing and thawing, using LWC structures which are effectively protected from the direct effects of climatic conditions significantly increases their durability; they can be considered frost resistant in moderately aggressive environmental conditions. In Figure 10a, we can see the contact zone between the bead and the binder before freezing. In this zone, the formation of a solid mass is observed. There are no cracks or other types of damage, either in the binder or in the EG bead. In Figure 10b, the view of the specimen after freezing is shown. Smaller or larger cracks are observed throughout the volume of the specimen. The largest cracks are observed in the pore walls of the EG bead, whereas individual small cracks are observed in the contact zone between the bead and the binder and in the binder layer itself. Since the pore walls of the EG beads are thin and weak, a large number of cracks form due to the freezing of water. Meanwhile, the small cracks that appeared in the contact zones between the bead and the binder and in the walls of the binder could have been caused both by the formation of small ice crystals and by the large stresses created in the EG aggregate during freezing. Figure 10: View of the LWC with EG aggregate: (**a**) before freezing test; (**b**) after 200 freeze–thaw cycles. In Figure 11, a comparison of the microstructure of LWC with EG beads and CEPW aggregate, before and after freezing tests, is shown. Figure 11a shows a view of the specimen before the freezing tests. Well-formed contact zones between EG, CEPW, and the cementitious matrix are observed. Several very small cracks are observed in the pore walls of EG beads, which may have appeared during the compaction of the mixture. There are no cracks in other areas, i.e., the cementitious matrix or CEPW. Figure 11b shows the view of the specimen after the freezing test. Some lager cracks are observed in the EG bead and cementitious matrix. These cracks terminate when they make contact with the CEPW. This means that CEPW has the potential to reduce cracking in LWC products. Since CEPW is sufficiently plastic, when water freezes in it, its walls do not crack but can move toward free space or expand. The comparison of LWC is complicated by the different compositions of the mixtures, and the amount of binder, additives, fillers, densities, production technologies, etc. Density mostly reflects the main performance characteristics of LWC. In terms of density, the LWC specimens obtained are very close to modified foam concrete products or specimens prepared with polystyrene foam beads [17; 23; 39]. [PERSON] et al. [23] indicated that after using blown perlite, glass sand, and foaming agent for the production of LWC, when 1 m\({}^{3}\) of concrete is composed of 100 kg of foam, the compressive strength obtained is close to  
Figure 11: View of the LWC with mixed aggregate: (**a**) before freezing; (**b**) after 200 freeze–thaw cycles. 1 MPa, the flexural strength ranges from 0.24-0.63 MPa, the compressive strength (after freezing) decreases to 36.2% after 25 cycles, and the bending strength decreases to 12.7%. The authors obtained a minimum density of 594 kg/m\({}^{3}\), so the thermal conductivity is much higher than in our research (0.17 W/(mK)). It should be noted that the authors obtained a very high absorption in water, which reached 54.5%, and, after almost doubling the density, they reduced the absorption to 21.6%. Additionally, the amount of foam was larger. When the authors used only 50 kg/m\({}^{3}\) foam, the absorption ranged from 25.1-15.3%. In another work [39], at a foam concrete density of 200-300 kg/m\({}^{3}\), the thermal conductivity varied from 0.06-0.08 W/(mK), and the compressive stress from 0.8-1.1 MPa. [PERSON] et al. [17] used EPS beads to replace part of the sand in the preparation of LWC.