## 2 Basic Mechanical Parameters  
The basic mechanical parameters of the coals and non-coal rocks in China were collected from the previous literature, as shown in Tables S1 and S2 in the Supplementary Material files. The statistical parameters of the basic mechanical parameters of coals and non-coal rocks are shown in Table 1. The detailed location of the coals and non-coal rocks in this study are shown in Figure 2. The basic mechanical parameters of coals and non-coal rocks are shown as Figure 3. From the statistical results, it can be concluded that the distribution ranges of basic mechanical parameters of non-coal rocks are much wider than that of coals, except for the Poisson ratio. The Poisson's ratios of coals and non-coal rocks share a similar distribution range, while the other three parameters have great differences in the distribution ranges. The ranges of \(\sigma_{c}\), \(\sigma_{t}\) and \(E\) are 0-50 MPa, 0-4 MPa and 0-46 GPa for coals, respectively, and 10-310 MPa, 0-20 MPa and 1-82 GPa for non-coal rocks, respectively. It can be easily found that the maximum uniaxial compressive strength of non-coal rocks is more than six times higher than that of coals. In addition, the maximum uniaxial tensile strength and maximum elastic modulus of non-coal rocks are about five times and two times higher than those of coals, respectively, and it is widely known that rocks with higher elastic modulus and uniaxial compressive strength generally have higher brittleness and stronger bursting liability [6; 28; 29; 30]. The basic mechanical parameters of coal and non-coal rocks were divided into four parts by the same division standard, and the proportion of data points in each interval was counted and plotted in Figure 4. It is obvious that the uniaxial compressive strength \(\sigma_{c}\), uniaxial tensile strength \(\sigma_{t}\), and elastic modulus \(E\) of coals are concentrated in the smallest interval, whereas, the above three parameters of non-coal rocks are mainly concentrated in the two medium intervals, as shown in Figure 4a-c. The Poisson's ratio proportion pie charts of non-coal rocks and coals have no significant differences, as shown in Figure 4d. These results indicate that there are considerable differences between the basic mechanical parameters of coals and those of non-coal rocks. It is thus questionable to evaluate the bursting liabilities of non-coal rocks by using the same classification criteria of coals. Takingthe uniaxial compressive strength as an example, the proportions of heavy bursting liability, weak bursting liability and no bursting liability for coals are 59.6%, 29.8%, and 10.7%, respectively, while they are 97.5%, 2.5%, and 0 for non-coal rocks when the bursting liability of non-coal rocks was evaluated by the uniaxial compressive strength classification criterion of coals, as shown in Figure 5. Therefore, it is necessary to define more reasonable evaluation criteria for non-coal rocks. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Statistical Parameter** & **Rock Type** & \(\sigma_{c}\)**/MPa** & \(\sigma_{t}\)**/MPa** & \(E\)**/GPa** & \(\mu\) \\ \hline \multirow{2}{*}{Variance} & coal & 94.19 & 0.68 & 58.41 & 0.005 \\ \cline{2-6}  & non-coal & 1964.89 & 12.89 & 385.65 & 0.003 \\ \hline \multirow{2}{*}{Standard deviation} & coal & 9.71 & 0.82 & 7.64 & 0.067 \\ \cline{2-6}  & non-coal & 44.33 & 3.59 & 19.64 & 0.056 \\ \hline \multirow{2}{*}{Median} & coal & 15.85 & 1.08 & 3.41 & 0.24 \\ \cline{2-6}  & non-coal & 94.10 & 6.48 & 26.23 & 0.23 \\ \hline \multirow{2}{*}{Maximum} & coal & 50.00 & 3.89 & 45.126 & 0.45 \\ \cline{2-6}  & non-coal & 313.00 & 19.07 & 81.381 & 0.455 \\ \hline \multirow{2}{*}{Mean} & coal & 17.46 & 1.18 & 5.87 & 0.26 \\ \cline{2-6}  & non-coal & 97.38 & 7.05 & 30.47 & 0.24 \\ \hline \multirow{2}{*}{Minimum} & coal & 1.36 & 0.07 & 0.039 & 0.09 \\ \cline{2-6}  & non-coal & 10.19 & 1.34 & 1.00 & 0.03 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Statistical parameters of the basic mechanical parameters of coals and non-coal rocks.