## 4 Results  
### Highway Rockfall Susceptibility Map  
After importing all the highway rockfall susceptibility elements into the GIS, the elements were first divided into different zones. In this research, the highway rockfall susceptibility elements were divided into various zones based on the actual situation in Guizhou Province in combination with expert opinions. Then, we calculated the information content in the GIS by counting the area of each interval and the number of hazard points. The information content in each zone is shown in Table 3.  
After determining the influence of each zone on highway rockfall susceptibility through the information content method, it was still necessary to use logistic regression to assign different weights. The specific steps are as follows: First, 250 rockfall hazard sites were randomly selected, and the same number of non-rockfall hazard sites were determined. Then the parameters of the highway rockfall susceptibility index corresponding to these random points were extracted. The data were then analyzed by logistic regression to derive the appropriate weights. Finally, the highway rockfall susceptibility map was created using the GIS. The results of logistic regression modeling are shown in Table 4. After calculating the highway rockfall susceptibility, the susceptibility was categorized into four levels of low, medium, high, and very high by the natural discontinuity method. The highway rockfall susceptibility map is shown in Figure 9. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Factor** & **Class** & \begin{tabular}{c} **Information** \\ **Value** \\ \end{tabular} & **Factor** & **Class** & \begin{tabular}{c} **Information** \\ **Value** \\ \end{tabular} \\ \hline Elevation & \begin{tabular}{c} \textless{}500 m \\ 500\(\sim\)1000 m \\ 1000\(\sim\)1500 m \\ 1000\(\sim\)1500 m \\ \end{tabular} & \begin{tabular}{c} \textless{}0.004715 \\ \textless{}0.052104 \\ 0.011811 \\ 0.073626 \\ 0.254924 \\ 0.146219 \\ 0.266531 \\ 0.094343 \\ 0.0863558 \\ 0.2–0.4 \\ 0.4–0.6 \\ 0.6–0.8 \\ 0.8 \\ 0.8 \\ \textless{}150\(\sim\)150 m \\ 150\(\sim\)300 m \\ 0.152283 \\ 0.045654 \\ 0.163818 \\ 0.2–0.4 \\ 0.267191 \\ fault \\ 1.5–3 km \\ 3–4.5 km \\ \textgreater{}4.5 km \\ \hline \hline \end{tabular} & \begin{tabular}{c} 1 \\ 2 \\ 3 \\ 4 \\ 5 \\ 6 \\ 7 \\ 8 \\ \end{tabular} & \begin{tabular}{c} 0.255183 \\ \textless{}0.110352 \\ \textless{}0.004681 \\ 0.1611609 \\ 0.058467 \\ 0.012289 \\ \textless{}0.034320 \\ \textless{}0.036404 \\ 0.002801 \\ 0.078364 \\ \textless{}0.018094 \\ 0.035378 \\ 0.045654 \\ \textless{}0.2–0.4 \\ 0.4–0.6 \\ 0.6–0.8 \\ 0.6–0.8 \\ 0.6–0.8 \\ 0.8 \\ 0.35773 \\ \end{tabular} & \
\begin{tabular}{c} 3 \\ 4 \\ 5 \\ 5 \\ 6 \\ 7 \\ \end{tabular} &
\begin{tabular}{c} 0.1611609 \\ \textless{}0.058467 \\ 0.012289 \\ \textless{}0.034320 \\ \textless{}0.036404 \\ \textless{}0.002801 \\ 0.078364 \\ \textless{}0.018094 \\ \textless{}0.035378 \\ \textless{}0.045654 \\ \textless{}0.2–0.4 \\ 0.4–0.6 \\ 0.6–0.8 \\ 0.6–0.8 \\ 0.6–0.8 \\ 0.8 \\ 0.35773 \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Information content of highway rockfall susceptibility. Based on the highway rockfall susceptibility map, it can be found that most of the study area is of high rockfall susceptibility and above. The percentage of high susceptibility regions reached 20%, while very high susceptibility regions reached 45%. This means that the entire study area may face rockfall accidents at any time, and the rockfall accident distribution map of Guizhou Province also shows that there have been a large number of rockfall accidents in the entire study area. According to the statistics, QDN and QN have the longest mileage of very high rockfall susceptibility. In addition, BJ and LPS have the highest percentage of low and medium rockfall susceptibility road mileage. The results of the highway rockfall susceptibility statistics for the entire study are shown in Figure 10.