## 9 Results and Discussion
### Predicted Maximum Effective Temperature Formula  
The discussions and comparisons conducted in the previous section revealed that the maximum effective temperature can be affected by environmental and geometric parameters. A regression analysis was conducted to develop a prediction model for the maximum effective temperature. In the regression analysis, the coefficient of determination R\({}^{2}\) and a \(p\)-value test (95% acceptance) were used to evaluate the model accuracy and to identify the significant parameters, respectively. The proposed model used for effective temperature prediction was developed based on the FE effective temperature data, which were determined based on the thermal analysis of the FE model that was verified using an experimental steel girder and thermal loads. Therefore, the proposed model can be consid \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Representative**} & \multicolumn{8}{c}{**Standard Steel I-Girders**} \\ \cline{2-9}  & **W36 \(\times\) 282** & **W36 \(\times\) 232** & **W30 \(\times\) 191** & **W30 \(\times\) 148** & **W18 \(\times\) 86** & **W18 \(\times\) 71** & **W10 \(\times\) 26** & **W10 \(\times\) 19** \\ \hline Toronto & 56.28 & 55.21 & 56.42 & 55.11 & 57.81 & 55.94 & 57.64 & 56.63 \\ \hline Winnipeg & 55.62 & 54.74 & 55.71 & 55.13 & 56.94 & 55.29 & 56.75 & 55.91 \\ \hline Halifax & 51.81 & 50.72 & 51.94 & 50.87 & 52.88 & 51.44 & 52.68 & 51.84 \\ \hline Victoria & 57.77 & 56.91 & 57.85 & 57.19 & 59.11 & 57.36 & 58.94 & 57.83 \\ \hline Whitehorse & 48.24 & 47.79 & 48.51 & 48.27 & 49.41 & 48.51 & 49.36 & 48.98 \\ \hline Yellowknife & 51.28 & 50.84 & 51.46 & 51.11 & 52.52 & 51.49 & 52.52 & 52.16 \\ \hline Iqaluit & 44.14 & 43.68 & 44.39 & 44.29 & 45.32 & 44.45 & 45.29 & 45.01 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: The FE maximum effective temperatures (\({}^{\circ}\)C) of the representative cities. ered reliable. Moreover, the effective temperatures of the CHBDC were determined based on air temperature data recorded decades ago, which are lower than the air temperature data used to determine the effective temperatures of FE, resulting in higher effective temperatures of FE than the corresponding effective temperatures of the CHBDC. Accordingly, the FE thermal model and the proposed model for effective temperature prediction are reliable. It was found that the daily maximum air temperature (DTa), flange width (b) and girder depth (d) are the prominent parameters forming the predicted maximum effective temperature formula. In addition, the effect of the flange width and the girder's depth should not be studied separately; instead, their combined effect should be considered. The predicted formula of the maximum effective temperature (PETmax) in \({}^{\circ}\)C is expressed in Equation (16). \[\text{PETmax}=8.80(\text{b})+0.94(\text{DTa})-4.98(\text{d})+22.54 \tag{16}\]  
Figure 11 shows that the predicted maximum effective temperatures are highly correlated with their corresponding FE maximum effective temperatures. The predicted formula shows a high correlation with a coefficient of determination R\({}^{2}\) of approximately 0.97. Comparison between the Predicted FE Thermal Results and the Corresponding Results Recommended by the CHBDC  
The maximum effective temperatures recommended by the CHBDC are calculated based on the air temperature and modified according to the superstructure's depth [1]. However, the FE maximum effective temperatures are not solely affected by the superstructure's depth. Instead, combining the superstructure's depth and flange width significantly affects the maximum effective temperatures. To observe the difference between the FE maximum effective temperatures and the CHBDC maximum effective temperatures, the extreme maximum effective temperatures recorded for W18 \(\times\) 86 were compared with their corresponding values recommended by the CHBDC.