## 3 Roadway Deformation Characteristics  
### Field Test  
Conducting a field investigation is a suitable way to understand the deformation failure characteristics of roadways visually and in detail. In this study, it was performed on the Jinchuan No. 2 Mine's panel (814 m above sea level with a burial depth of approximately 1000 m). To provide tangible data for the adoption of appropriate support measures, the investigation included the rock mass strength, support patterns, ground stress, construction methods and other factors that impact the stability of deep roadways. There are five main lithology types in the survey area, and Table 1 shows the mechanical and physical parameters of these intact rocks and rock masses. It can be seen that the intact rock has a high  
Figure 1: Engineering geological background of the Jinchuan Mine. (**a**) Jinchuan Mine’s location and geology. (**b**) Jinchuan No.2 Mine’s geological section along an exploratory line. strength compared to that of the rock mass. Therefore, the roadway is very weak. Furthermore, the ultrabasic rock mass has better engineering geological conditions than the marble rock mass. [PERSON] et al. [31] studied the geo-stress in Jinchuan mining for several years, based on a hollow inclusion strain gauge. They measured six points in the study area, and Table 2 displays the stress parameters of each point. It is illustrated that the maximum principal stress reaches 46.6 MPa and the gap between the minimum and maximum principal stress is huge, which indicates a high shear stress. The test roadway's initial support was a compound support scheme. It consisted of a bolt-mesh-anchor (double layer) and U-shaped steel, as depicted in Figure 3. The cement mortar anchor rod was constructed with secondary rebar (spacing, \(1000\times 1000\) mm; length, 2250 mm; diameter, 22 mm). An ordinary steel plate (thickness,10 mm; size, \(200\times 200\) mm) was utilized to make an anchor \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline
**Lithology** & **Type** & \begin{tabular}{c} **Density** \\ **(g cm-3)** \\ \end{tabular} & \begin{tabular}{c} **Tensile Strength** \\ **(MPa)** \\ \end{tabular} & \begin{tabular}{c} **Compressive** \\ **Strength** \\ **(MPa)** \\ \end{tabular} & \begin{tabular}{c} **Cohesion** \\ **(MPa)** \\ \end{tabular} & \begin{tabular}{c} **Internal** \\ **Friction Angle** \\ **(C)** \\ \end{tabular} & \
\begin{tabular}{c} **Elastic Moduli** \\ **Ratio** \\ \end{tabular} &
\begin{tabular}{c} **Poisson’s** \\ **Ratio** \\ \end{tabular} & **RMR** \\ \hline \multirow{2}{*}{Markle} & Intact rock & 2.86 & 11.00 & 104.0 & 9.5 & 42.0 & 64.0 & 0.16 & - \\  & Rock mass & 2.40 & 0.80 & 15.0 & 0.7 & 35.0 & 6.0 & 0.26 & 39.56 \\ \hline \multirow{2}{*}{Mignantile} & Intact rock & 2.73 & 9.09 & 51.9 & 15.5 & 32.0 & 55.0 & 0.15 & - \\  & Rock mass & 2.45 & 1.00 & 17.0 & 0.8 & 35.0 & 6.4 & 0.25 & 40.27 \\ \multirow{2}{*}{Ultrezhastic rock} & Interpolie & 2.93 & 13.00 & 150.0 & 11.5 & 43.5 & 95.0 & 0.23 & - \\  & Rich one & 3.02 & 9.60 & 73.5 & 10.0 & 45.0 & 70.0 & 0.22 & - \\  & Poor ore & 3.05 & 6.60 & 70.0 & 7.0 & 43.5 & 65.0 & 0.31 & - \\  & Rock mass & 2.50 & 2.20 & 25.0 & 0.8 & 38.0 & 7.0 & 0.24 & 43.23 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Mechanical and physical parameters of rocks and rock masses.