## 4 Materials and Methods  
As part of the experimental research, a concrete mix of ordinary cobs C20/25 on consistency S2 was designed according to the PN-EN 206+A2:2021-08 method of three equations by [PERSON]. The concrete mix was made of CEM I 42.5 R Portland cement (Cement O\(\check{\text{z}}\)arow SA, O\(\check{\text{z}}\)arow, Poland), in accordance with the requirements specified in PN-EN 197-1:2012; natural slag with a 0-16 mm according to PN-EN 12620+A1:2010; and water compliant with PN-EN 1008:2004. The components of the mixture are show in Figure 2. In all of the tests, the same scrapper composition was collected at the base of the curved crossings 0-16 mm (Figure 3). As a mineral supplement to the concrete mix, a fly ash from the fluid combustion of municipal settlements in the \"Plazow II\" sowing plant in Krakow was used. The physical and chemical parameters, and the phase composition of Portland cement used are shown in Tables 1 and 2. The incineration technology for high-pressure fluids at a temperature of around 900 \({}^{\circ}\)C, generally used for candles, is the most effective method of thermal transfer. It guarantees both apartment security and protects the environment. The resulting fly ash is a dry material of a characteristic red-pink color, which varies greatly from ash derived from ash burning, the color of which oscillates in the rock [45; 46; 47; 48]. Figure 2: Concrete mixers: cement, settlement ash, leachate: (**A**) cement; (**B**) natural slag; (**C**) aggregate. To carry out the analysis of the possibility of exploitation as a partial substitute for cement ash in the areas of thermal rescue of prepared settlements, the mixture was prepared based on the various content of the supplement (0%, 5%, 10%, 15%, 20%)--completing the optimization of water and cement and considering the volume of the interchangeable components--Table 3. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Specific Surface Area** & **Beginning of Binding Time** & **Compressive Strength after** & **Compressive Strength after** \\
**Blaine’a [cm2/g]** & **[min]** & **2 Days [MPa]** & **28 Days [MPa]** \\ \hline
3328 & 219 & 21.0 & 49.7 \\ \hline \multicolumn{3}{c}{The share of mineral phases CEM 1 [5 mass]} \\ \hline C\({}_{3}\)S—55.53 & C\({}_{2}\)S—14.58 & C\({}_{3}\)A—8.16 & C\({}_{4}\)AF—6.84 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Physical properties and phase composition of cement CEM 1 42.5 R. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Roasting Loss [\%]** & **Sulfate Content SO\({}_{3}\) [\%]** & **Chloride Content Cl [\%]** & **Alkali Content Na\({}_{2}\)O\({}_{\text{eq}}\) [\%]** & **SiO\({}_{2}\) [\%]** \\ \hline
3.18 & 2.97 & 0.05 & 0.76 & 20.20 \\ \hline Al\({}_{2}\)O\({}_{3}\) & Fe\({}_{2}\)O\({}_{3}\) & CaO & CaO\({}_{\text{w}}\) & MgO \\ \hline
4.40 & 2.43 & 64.37 & 1.97 & 1.98 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Chemical properties of cement CEM 1 42.5R. Figure 3: The concrete is crushed into a concrete mixer. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Specification** & \multicolumn{4}{c}{**Mass of Concrete Ingredients [kg/m3]**} \\ \cline{2-5}  & **Water** & **Aggregate** & **Cement** & **Fly Ash** \\ \hline Concrete BZ & 187.11 & 1834.27 & 374.21 & - \\ \hline Concrete with quantity 5\% of fly ash—FA5\% & 187.11 & 1834.27 & 355.50 & 18.71 \\ \hline Concrete with quantity 10\% of fly ash—FA10\% & 187.11 & 1834.27 & 336.79 & 37.42 \\ \hline Concrete with quantity 15\% of fly ash—FA15\% & 187.11 & 1834.27 & 318.08 & 56.13 \\ \hline Concrete with quantity 20\% of fly ash—FA20\% & 187.11 & 1834.27 & 299.37 & 74.84 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Concrete mix proportions by weight. As part of the evaluation of the properties of the concrete mix with the addition of fly ash from the thermal treatment of sewage sludge, tests were performed on the prepared slurries: apparent density (PN-EN 12350-6:2011); consistency by the drop cone method (PN-EN 12350-2:2011); and the pressure method air content (PN-EN 12350-7:2011).