# Thermomechanical Behavior of Textile Reinforced Cementitious Composites Subjected to Fire
## 3 Results and Discussion
### Bending Tests Results
#### 3.4.1 Results from 15-Minute Fire Tests  
The only case where the specimens with SBR coated textiles presented a countable residual strength was the 15-min fire test. Even though the temperature at the level of the effective depth was not measured, by assuming a linear reduction of the temperature between the surface and the middle (where the temperatures are known), it was deduced that the temperature at the level of the effective depth was below 400 \({}^{\circ}\)C. However, as a precise calculation cannot be made, no numerical value is provided. Taking this estimation into account, it is not expected to have a severe degradation of the specimens of Series E, for the following reasons:  
* The mass loss of the coating is in the order of 20% or lower (see Figure 7); therefore, since most of the coating is still in place, the bond between the textiles and the mortar will not be completely lost as in Series A, B, C, D and F.
* Even though it is well-known that glass fibers lose their strength after being exposed to temperatures higher than 300 \({}^{\circ}\)C, it is also well known that carbon fibers maintain their capacity to even higher temperatures if they are not in oxidizing atmosphere [31]. Therefore, even though the glass fibers within the specimens of Series E do not provide significant load bearing capacity, the carbon fibers do. * The matrix was exposed to a maximum temperature of 477 \({}^{\circ}\)C at the surface (face 2), while at the bottom side (face 1, which is subjected in compression at the flexural test, thus, it is the most contributing part of the mortar) the maximum temperature reached 317 \({}^{\circ}\)C. According to Table 4, the degradation of the mortar is also not critical. The loss of compressive strength is close to 20% (interpolation between 5% and 36%), while the reduction of the elastic modulus is close to 48% (interpolation between 23% and 72%). \begin{table}
\begin{tabular}{c c c} \hline \hline
**Temperature (\({}^{\circ}\)C)** & **Reduction of Compressive Strength** & **Reduction of Elastic Modulus** \\ \hline
20 & - & - \\
200 & 5\% & 23\% \\
400 & 36\% & 72\% \\
500 & 63\% & 82\% \\
700 & 71\% & 85\% \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Reduction of compressive strength and elastic modulus of TRC after exposure to high temperatures. Figure 8: Reduction of compressive strength and elastic modulus of textile reinforced concrete (TRC) specimens after exposure to elevated temperatures. Figure 9 gives the comparison between the load-bearing capacity of the not subjected and the subjected to fire testing specimens in Series E. In the same figure the dashed lines correspond to the specimens that were tested \"upside-down\", which means that instead of having face 2 subjected to tension during bending, they had face 1. Additionally, for the specimen that was subjected to the fire test before the flexural test, it was again face 1 instead of face 2 that was directly exposed to fire. The reason why this happened was the difference in the concrete cover, since the specimens in Series E had a cover of 8 mm at face 2 and a cover of 4 mm at face 1. Of course, the effective depth during bending changed; thus, these two specimens cannot be compared to the others regarding their flexural strength (higher effective depth, and thus, higher flexural strength, as can be seen from the result of the not exposed specimen-the blue dashed line). However, it can be observed that the reduction of the load recorded for the exposed to fire specimen is greater than the respective reduction in the other specimens (not tested \"upside down\"-continuous blue lines). This is not surprising, because the concrete cover in the former case was smaller, thus, a heavier damage was done to the textiles at the level of the effective depth, as a result of the higher temperature reached.