# Efficacy of Fire Protection Techniques on Impact Resistance of Self-Compacting Concrete
## 3 Results and Discussion
### Failure Impact Energy of SCC Specimens  
Figure 8a,b depict the variations in failure impact energy and the corresponding number of blows for the unprotected (FA and GGBFS) and protected SCC specimens subjected to high temperatures. The results of impact energy failure revealed that the specimens with CPP coating containing EPA demonstrated superior performance under impact loading conditions. This can be attributed to the enhanced thermal compatibility of  
Figure 7: Failure impact energy (represented by histograms) and the number of blows of unprotected SSCC specimens subjected to high temperature (represented by the line), (a) FA and GGBFS, (b) FA/EPA and GGBFS/EPA. the CPP layers, which effectively limited the transfer of heat transfer into the core of the SCC, resulting in reduced impact energy. Generally, the failure energy decreased as the intensity of exposure and the duration of heating increased. The graphical examination indicated that the SCC specimens incorporating EPA and protected by a CPP layer, FA/EPA/CPP and GGBFS/EPA/CPP, exhibited superior performance across all exposure conditions. The FA/EPA/CPP 30M specimen exhibited a loss in failure impact energy of about 15.56%, while it was 80% for unprotected FA 30M specimens. The difference in the failure impact energy loss of GGBFS/EPA/CPP 30M and GGBFS 30M compared to that of the GGBFS 0M specimen was about 3.6% and 90%, respectively. The efficiency of the CPP coating in combination with the EPA content in withstanding high temperatures is evident  
Figure 8: **(a)** Failure impact energy (represented by histograms) and the corresponding number of blows of protected SCC (FA) specimens exposed to elevated temperature (represented by the dots). **(b)** Failure impact energy (represented by histograms) and the corresponding number of blows of protected SCC (GGBFS) specimens exposed to elevated temperature (represented by the dots). from the comparison. EPA's enhanced thermal compatibility nature gives it a unique property [32; 33]. The heated specimens FA/EPA/CPP 60M and GGBFS/EPA/CPP 60M exhibited impact energy losses of 33.3% and 24.6%, respectively, compared to the FA 0M and GGBFS 0M specimens. On the other hand, the unprotected heated specimens FA 60M and GGBFS 60M demonstrated significantly higher impact energy losses of approximately 86.7% and 91.8%, respectively, when compared to the FA 0M and GGBFS 0M specimens. The failure impacts energy values of SCC-FA and SCC-GGBFS specimens are presented in Tables 6 and 7, respectively. The loss in failure impact energy for the FA/EPA/CPP 120M specimen was approximately 44.44%, whereas the unprotected FA 90M specimens showed a loss of 88.9%. The reduction in failure impact energy for GGBFS/EPA/CPP 30M and GGBFS 30M specimens compared to the GGBFS 0M specimen was approximately 37.3% and 92.7%, respectively. All test specimens experienced a rapid decline in failure impact energy when temperature exposure exceeded 120 min. However, the protected specimens could limit energy loss compared to the unprotected ones [38]. The loss in impact energy for 120 min of heated FA/EPA/CPP and GGBFS/EPA/CPP was 64.4% and 60.0%, respectively, compared to FA 0M and GGBFS 0M specimens. Unprotected heated specimens (FA 120M and GGBFS 120M) showed a significantly more significant loss in impact energy of around 95.6% and 93.6%, respectively, compared to FA 0M and GGBFS 0M specimens. The study found that even after 120 min of heating, the CPP-protected SCC specimens containing EPA effectively resisted temperature penetration and reduced the loss in failure impact energy [39]. During the heating period, measurements were taken to determine the time-temperature behaviour of various specimens, including FA, FA/EPA, FA/CPP, FA/EPA/CPP, GGBFS/EPA, GGBFS/CPP, and GGBFS/EPA/CPP. Temperatures were recorded at each specimen's surface, protective layer, and core. For FA/EPA specimens exposed to 60 min of heating, the measured temperatures were 918 \({}^{\circ}\)C at the concrete surface and 613 \({}^{\circ}\)C at the core.