Figure 1.
Examples of aeration admixtures used in renovation plasters Figure 2.
Figure 2.
An example of a hydrophobizing admixture
Table 1.
The composition of dry mixtures of plaster mortars
| Components | Symbols and compositions of dry mixtures, (% by weight) | |||||
|---|---|---|---|---|---|---|
| S 1 | S 2 | S 3 | S 4 | S 5 | S 6 | |
| Portland cement CEM I52.5 R | 15 | 15 | 15 | 15 | 15 | 15 |
| Quartz sand 0.0 ÷ 1.0 mm | 73.66 | 73.36 | 73.15 | 72.34 | 74.69 | 73.84 |
| Limestone powder 45 μm | 5 | 5 | 5 | 5 | 5 | 5 |
| Hydrated lime Ca (OH)2 | 5 | 5 | 5 | 5 | 5 | 5 |
| Pearlite | 1 | 1 | 1.5 | 2 | - | 0.5 |
| HEMC (Hydroxyethyl methyl cellulose) | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.13 |
| PVAc (Poly vinyl acetate) | 0.2 | 0.5 | 0.2 | 0.5 | 0.2 | 0.5 |
| Aerator 1 | 0.04 | 0.04 | 0.05 | 0.06 | 0.01 | 0.03 |
| Aerator 2 | 0.005 | 0.01 | 0.005 | 0.01 | – | – |
| Water * | 24 | 23 | 25 | 26 | 24 | 23 |
| w/c | 1.6 | 1.53 | 1.67 | 1.73 | 1.6 | 1.53 |
Table 2.
Porosity Pc (%), pore volume as a function of radii, as total porosity percentage (%), density (kg/dm3) of the studied plasters
| Symbol | Total porosity (% vol) | Radius of capillaries (μm) | Density (kg/dm3) | |||||
|---|---|---|---|---|---|---|---|---|
| <0.01 | 0.01÷0.1 | 0.1–1.0 | 1.0–10 | 10–100 | >100 | |||
| Percentage of pore volume (%) | ||||||||
| S1 | 41.6 | – | 4.5 | 15.6 | 32.3 | 34.8 | 12.8 | 1.35 |
| S2 | 45.4 | – | 3.7 | 13.4 | 27.9 | 34.5 | 20.5 | 1.31 |
| S3 | 52.1 | – | 3.2 | 11.9 | 28.9 | 38.7 | 17.3 | 1.11 |
| S4 | 58.4 | – | 6.2 | 11.6 | 27.8 | 38.5 | 15.9 | 1.03 |
| S5 | 24.5 | 2.3 | 12.7 | 69.7 | 12.7 | 2.3 | 0.3 | 1.55 |
| S6 | 32.7 | 3.0 | 9.7 | 14.0 | 66.9 | 5.6 | 0.8 | 1.45 |
Figure 3.
The curves for differential pore volume distribution (Fig. 3a) and capillary volume distribution depending on their effective radii for samples S1–S4 (Fig. 3b)
Figure 4.
The curves for differential pore volume distribution (Fig. 4a) and capillary volume distribution depending on their effective radii for plasters of S5–S6 mortars (Fig. 4b)
Figure 5.
The influence of the amount of aeration admixtures 1 and 2 on the porosity Pc (%) (Fig. 5a), pore volume distribution depending on the effective radii (Fig. 5b)
Figure 6.
The impact of the amount of H1, H2 and H3 hydrophobizing admixtures on the porosity with a fixed amount of aeration admixtures 1 and 2 (0.06% and 0.01%) (Fig. 6a); comparison of the porosity of the plaster without hydrophobic admixtures with plasters containing hydrophobizing admixtures H1, H2 and H3 (Fig. 6b)