# The Influence of Steel, Glass and Basalt Fibres on Selected Parameters of Construction Mortars
## 3 Results  
The rheological tests were performed to determine the consistency based on the PN-EN 1015-6:2000 standard [50] using the flow table method, and the volume density of fresh mortar was determined. The test was carried out in accordance with PN-EN 1015-3:2000 [51] (Table 3). According to PN-EN 1015-6:2000 [50], mortars with a spread value of less than 140 mm belong to the group of dense-plastic mortars. The addition of fibres to mortars significantly changed the volumetric density of the mortars. This study showed that the contribution of glass, basalt and steel fibres resulted in an increase in volumetric density compared to the reference series. When glass fibres were used, the volumetric density increased by 7.67% relative to the SW sample, while for steel fibres, there was an increase of as much as 14.44% relative to the reference series (Table 3). Based on scientific research conducted to date, it can be concluded that the rheological properties of mortars with fibre additives depend primarily on the parameters of the fibres and the W/C ratio. With the addition of fibres, the rheological properties of mortars deteriorate. Similar conclusions were reached by [PERSON] and [PERSON] [52]. The results of the WRV10 water retention index tests for all mortars tested, together with data and auxiliary calculation results, are presented in Tables 4 and 5. \begin{table}
\begin{tabular}{l c c} \hline \hline
**Series Name** & **Spreading, [mm]** & **Volumetric Density, [g/cm\({}^{3}\)]** \\ \hline SW & 115 & 1.80 \\ \hline ST & 107 & 2.06 \\ \hline SZ & 105 & 1.94 \\ \hline SB & 110 & 2.01 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Results of consistency and bulk density measurements of fresh mortars. The water retention (Tables 4 and 5) index of the reference mortar SW after 10 min of measurement was 89.0%. The lowest WRV10 index was recorded for mortar with glass fibres added. WRV10 for the reference mortar was 4.38% higher than for mortar with glass fibres. The highest index was recorded for mortar with basalt fibres. It is 3.36% higher than the reference series. Figure 6 shows the average increase in compressive strength for the tested series of mortars with the addition of selected fibres. The determination of compressive and flexural strength was performed on three standard specimens of 4 cm \(\times\) 4 cm \(\times\) 16 cm according to PN-EN 1015-11:2020-04 [48]. An analysis of the results of tests conducted by [PERSON] and [PERSON] [7] on compressive strength shows that steel fibres added in quantities of up to 1% of the volume effectively increase this strength. Above this level, there is no significant increase in compressive \begin{table}
\begin{tabular}{c c c c c c c} \hline
**Series Name** & **Dry Weight of Filter Paper [g]** & **Wet Filter Paper** & **Empty Set** & **Weight of Set** & **Weight of Set** & **Water Absorbed** \\  & **Filter Paper [g]** & **Mass [g]** & **Weight [g]** & **with Mortar [g]** & **Mortar [g]** & **by Filter Paper** \\ \hline SW & 42.4 & 47.1 & 229.5 & 615.3 & 385.8 & 4.7 \\ \hline SZ & 42.3 & 46.58 & 193.5 & 578.8 & 385.3 & 4.28 \\ \hline ST & 41.5 & 47.15 & 227.3 & 618.8 & 391.5 & 5.65 \\ \hline SB & 41.2 & & 214.9 & 599.3 & 384.4 & 3.38 \\ \hline \end{tabular}
\end{table} 
Table 4: Data required to calculate the WRV10. Figure 6: Average compressive strength gain of the tested series. \begin{table}
\begin{tabular}{p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt}} \hline
**Series Name** & **Water Content in Mortar W1 [\%]** & **Water Content in Matrix in Plastic Ring W2 [g]** & **Water Absorbed by the W3 Filter Paper [g]** & **Relative Water Loss in Mortar W4 [\%]** & **Water Retention Index, WRV10 [\%]** \\ \hline SW & 11.11 & 42.87 & 4.7 & 10.96 & 89 \\ \hline SZ & 11.11 & 45.11 & 6.71 & 14.87 & 85.1 \\ \hline ST & 11.11 & 43.5 & 5.65 & 12.99 & 87 \\ \hline SB & 11.11 & 42.71 & 3.38 & 7.91 & 92.1 \\ \hline \end{tabular}
\end{table} 
Table 5: Water retention index, WRV10. strength.