## 4 Results
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Influence Factor** & **Parameter** & **Symbol** & **Value** & **Unit** \\ \hline \multirow{6}{*}{Vehicle} & Mass & \(m\) & 30,000 & kg \\  & Height of the CG & \(h_{g}\) & 1.8 & m \\  & Synchronous adhesion coefficient & \(\varphi_{0}\) & 0.4 & \\  & Front axle to CG distance & \(a\) & 3.60 & m \\  & Rear axle to CG distance & \(b\) & 4.25 & m \\ \hline \multirow{6}{*}{Road} & Design speed & \(V_{\text{DS}}\) & 80 & km/h \\  & Radius & \(R\) & 250 & m \\ \cline{1-1}  & Superelevation & \(i_{h}\) & 8 & \% \\ \cline{1-1}  & Downgrade & \(i\) & 1/2/3/4/5/6 & \% \\ \cline{1-1}  & Friction coefficient (tire–pavement) & \(\mu_{x,max}\) & 0.6 & \\ \hline Environment & Weather & & Dry & \\ \hline \multirow{2}{*}{Driver behavior} & Speed & \(V\) & 80 & km/h \\  & Deceleration & \(a_{x}\) & 0–5.5 & m/s\({}^{2}\) \\ \hline \hline \end{tabular} Note: The blue-filled areas indicate that the impact of changes in these variables on truck skidding is being explored.  
\end{table} 
Table 3: Parameter values. Figure 9: Prediction of truck skidding potential and recommendations of the MSBDRs on horizontal curves with different curve radii. Note: The area highlighted in orange indicates a high potential of skidding. The results in Figure 10 show that:  
* The downgrade has an effect on truck skidding. * During braking, a horizontal curve with steep slopes is more prone to inducing truck skidding compared to a single horizontal curve. The larger the downgrade rates, the higher the potential of truck skidding. * During significant and emergency braking maneuvers, trucks traveling on horizontal curves with steep slopes have a higher skidding potential. * Therefore, the recommended MSBDR is 4 m/s\({}^{2}\) on horizontal curves with steep slopes. The results in Figure 11 show that:  
* The friction coefficient has a significant effect on truck skidding. * The combination of braking and wet road conditions is worse for driving. * During braking, the lower the friction coefficient, the higher the potential of truck skidding. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Influence Factor** & **Parameter** & **Symbol** & **Value** & **Unit** \\ \hline \multirow{6}{*}{Vehicle} & Mass & \(m\) & 30,000 & kg \\  & Height of the CG & \(h_{g}\) & 1.8 & m \\  & Synchronous adhesion coefficient & \(\varphi_{0}\) & 0.4 & \\  & Front axle to CG distance & \(a\) & 3.60 & m \\  & Rear axle to CG distance & \(b\) & 4.25 & m \\ \hline \multirow{6}{*}{Road} & Design speed & \(V_{DS}\) & 80 & km/h \\  & Radius & \(R\) & 250 & m \\  & Superelevation & \(i_{h}\) & 8 & \% \\  & Downgrade & \(i\) & 0 & \% \\  & Friction coefficient (tire-pavament) & \(h_{\pi,max}\) & 0.6/0.5/0.44/0.34 & \\ \hline Environment & Weather & \multicolumn{3}{c}{Dry/wet} \\ \hline \multirow{2}{*}{Driver behavior} & Speed & \(V\) & 80 & km/h \\  & Deceleration & \(a_{x}\) & 0-5.5 & m/s\({}^{2}\) \\ \hline \hline \end{tabular} Note: The blue-filled areas indicate that the impact of changes in these variables on truck skidding is being explored.  
\end{table} 
Table 4: Parameter values. Figure 10: Prediction of truck skidding potential and recommendations of the MSBDRs on horizontal curves with different slopes. Note: The area highlighted in orange indicates a high potential of skidding. * On extremely wet roads (roads with a lower friction coefficient), even during stopping-sight-distance braking maneuvers, there is a higher potential of truck skidding. * Therefore, the recommended MSBDR is 2 m/s\({}^{2}\) on an extremely wet horizontal curve. The results in Figure 12 show that:  
* Driving speed has a significant effect on truck skidding. * The combination of braking and speeding is worse for driving. * During braking, the more excessive the speeding, the higher the potential of truck skidding. * In cases of excessive speeding, during significant and emergency braking maneuvers, there is a higher potential of truck skidding.