# Development of Passive Fire Protection Mortars
## 3 Results and Discussion
### Steel Plate Specimens
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Mortar** & \multicolumn{3}{c}{**Without NS and MS**} & \multicolumn{3}{c}{**With NS and MS**} \\ \cline{2-7}
**Designation** & **LA Method** & **SD** & **IM Method** & **SD** & **LA Method** & **SD** & **IM Method** & **SD** \\ \hline CM & 310.7 & 13.5 & (*) & - & (*) & - & (*) & - \\ DCM & 293.0 & 14.5 & 308.5 & 13.7 & 307.8 & 8.6 & 296.7 & 14.1 \\ DGMP & 310.3 & 7.5 & 324.8 & 18.1 & 274.8 & 7.0 & 273.6 & 3.7 \\ DGMV & 278.2 & 6.1 & 275.2 & 2.3 & 268.4 & 6.5 & 266.1 & 4.1 \\ DRCM & 322.9 & 29.0 & 366.2 & 7.6 & (**) & - & (**) & - \\ \hline \hline \end{tabular}  
* The commercial solution was not modified, so there was no need to test more than three specimens. (**) Since this mortar has the worst results in the first phase (without NS and MS), it has not been tested with the addition of silica micro- and nanoparticles.  
\end{table} 
Table 5: Average values and corresponding standard deviation of the maximum temperature (\({}^{\circ}\)C) on the inner surface of the specimen’s steel plate. raw materials used (perlite and vermiculite) did not benefit the thermal performance of the tested compositions. Note that the reduction in the porosity of mortars may have an adverse effect in the fire insulation, but only neglecting the thermomechanical effect of mortars and the thermal deformation of the structural members, as it was the case in the thermal tests of the protected steel plates. Finally, compared to the commercial mortar with the developed mortals, DCM (cementitious mortar) and DGMV (gypsum mortar with vermiculite) had greater thermal insulation capacity, while mortars DGMP (gypsum mortar with vermiculite) and DRCM (refractory cementitious mortar) had lower thermal insulation capacity. The sixth column of Table 5 refers to mortars developed with NS and MS, and the raw materials used were obtained by the LA method. This column only presents the results of the tests carried out with DCM, DGMP, and DGMV since the results of DRCM never presented a thermal insulation capacity higher than the commercial solution. The average temperature on the ISSP in the DCM, DGMP, and DGMV were 308, 275, and 268 \({}^{\circ}\)C, respectively. It appears that the introduction of NS and MS in the tested dosages slightly improved the thermal performance of the mortars by 11.3% for DGMP and 3.6% for DGMV. Comparing to CM (commercial mortal), both developed mortars with NS and MS (A2, A3, and A4) had greater thermal insulation capacity than the mortars without such particles. Values for mortars with NS and MS and raw materials obtained by the IM method are presented in the eighth column. The average temperature in the ISSP in the DCM, DGMP, and DGMV were 297, 274, and 266 \({}^{\circ}\)C, respectively. The results demonstrate that the thermal protection provided by DCM, DGMP, and DGMV were 4.5%, 11.9%, and 14.5% thermally more efficient than CM, respectively. Comparing these results with those of the fourth column, the addition of NS and MS in DCM, DGMP, and DGMV improved their thermal performance by 3.9%, 15.7%, and 3.3%, respectively. In addition, comparing these results with those of the sixth column, the manufacture of DCM, DGMP, and DGMV with raw materials processed with the IM method gives only a slight benefit on the thermal performance of these compositions, by 3.6%, 0.4%, and 0.8%, since nanoparticles tend to increase the shrinkage of materials. This is due to stronger retention of water, and capillary forces developed. Briefly, the differences in the results presented may be due to the higher porosity of the materials obtained through the LA method than the IM method, i.e., in general the higher the porosity, the higher the thermal insulation is. However when micro- and nanoparticles of silica were added, the thermal responce of fire protection materials might be different (as it was the case) since those particles can work as fire barriers, i.e., close more efficiently some porous in the materials.