## 3 Experiment
### Production and Basic Properties of the Developed MM Variants  
The preparation of all MMs was identical. After fine-tuning the amount of the plasticizer, MMs for all the samples were prepared using a cement mixer. The parameters of the mixer are standardized according to several standards (EN 196-1 [32], EN 196-3 [33], ASTM C305 [34], etc.). The mixer includes a programmed mixing cycle which allows mixing of all MMs in exactly the same way. The amount of the plasticizing/multifunctional admixture was selected so that the spread of the prepared MM was in the range of 190 mm to 210 mm, see Figure 5. The only exception was the M1 mortar. It simulated concrete with poor workability used in the straight section of pipes and in the test according to Figure 5 formed a compact truncated cone which did not flow. After fine-tuning the consistency of all the mortars, each MM for the following tests was produced in one mixture with a volume of 1.25 L. The following test specimens were produced:  
* samples 40 \(\times\) 40 \(\times\) 160 mm--3 pcs;
* samples 22 \(\times\) 22 \(\times\) 120 mm--8 pcs. \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline
**Component** & **Unit** & **M1** & **M2** & **M3** & **M4** & **M5** & **M6** & **M7** & **M8** & M8(a) \\ \hline CEM 142.5 R & kg/m\({}^{3}\) & 578 & 570 & 568 & 832 & 500 & 710 & 630 & 630 & 606 \\ FGL V8 & kg/m\({}^{3}\) & 68 & 300 & 298 & 117 & & 240 & 113 & 113 & 108 \\ GBPS SMS 400 & kg/m\({}^{3}\) & & & & & & 500 & & 100 & 150 & 150 & 144 \\ MK Meifisto L05 & kg/m\({}^{3}\) & & & & 11.4 & & & & & & & \\ Xypex Admix C-1000 & kg/m\({}^{3}\) & & & 11.0 & 16.0 & & & & & & & \\ STACHEMENT 2180 & kg/m\({}^{3}\) & & & & 10.0/S8 & 10.0/S9 & 10.0/S1 & & & & & \\ special PCE admixture & kg/m\({}^{3}\) & & & & & 10.0/S8 & 10.0/S9 & 10.0/S1 & & & & \\ PowerFlow 2695 & kg/m\({}^{3}\) & 5.2 & & & & & 10 & 14.0 & & & \\ PowerFlow 3196 & kg/m\({}^{3}\) & & & & & & & & 11.0 & 10.6 \\ Centrament Retard 360 & kg/m\({}^{3}\) & & & & & & & 1.5 & 1.5 & 1.4 \\ water & kg/m\({}^{3}\) & 204 & 245 & 245 & 245 & 248 & 248 & 206 & 206 & 198 \\ SIS 0.1–1.0 mm & kg/m\({}^{3}\) & 903 & 738 & 735 & 730 & 683 & 641 & 749 & 751 & 722 \\ SIS 0.3–1.6 mm & kg/m\({}^{3}\) & 602 & 442 & 440 & 393 & 427 & 368 & 498 & 498 & 479 \\ \hline density—theoretical & kg/m\({}^{3}\) & 2360 & 2306 & 2312 & 2327 & 2359 & 2318 & 2361 & 2360 & 2266 \\ density—real 7d & kg/m\({}^{3}\) & 2281 & 2224 & 2217 & 2316 & 2355 & 2296 & 2359 & 2269 \\ \hline flexural strength 7d & N/mm\({}^{2}\) & 8.2 & 9.8 & 9.2 & 11.2 & 9.2 & 10.7 & 10.1 & 9.4 \\  & & (1.1) & (0.2) & (2.9) & (3.2) & (0.8) & (0.9) & (1.1) & (1.1) \\  & & 68.1 & 67.9 & 65.4 & 94.1 & 105.2 & 97.1 & 92.8 & 81.9 \\ compressive strength 7d & N/mm\({}^{2}\) & (3.9) & (3.4) & (4.8) & (6.5) & (4.7) & (4.7) & (3.3) & (0.2) \\ compressive strength 28d & N/mm\({}^{2}\) & 78.9 & 71.1 & 68.2 & 111.6 & 134.4 & 114.9 & 110.7 & 93.4 \\  & & (5.7) & (3.2) & (4.1) & (1.1) & (2.3) & (3.1) & (5.2) & (6.2) \\ \hline \hline \end{tabular} Note: The PowerFlow 3196 introduced an approximately 4% air-entrainment into the original mixture, so M8(a) represents M8 composition including 4% air-entrainment (=40 L/m\({}^{3}\)); theoretical values are shown in brown.  
\end{table} 
Table 2: Composition and parameters of all tested MMs (sample standard deviations are in brackets). Figure 5: Principle of mortar spread measurement. There were a total of 11 test specimens for each MM. The test specimens 40 \(\times\) 40 \(\times\) 160 mm were produced using precise steel molds in accordance with EN 196-1 [32] and employed for the determination of:  
* density according to EN 12390-3 [35] at the age of 7 days;
* flexural strength according to [32] at the age of 7 days;
* compressive strength according to [32] at the age of 7 days (always on one fraction of each of the 3 specimens);
* compressive strength at the age of 28 days (on the second fraction of each of the 3 specimens).