# Deep Soft Rock Tunnel Perimeter Rock Control Technology and Research
## 3 Engineering Application of Roadway Support Technology
### Determination of the Physical and Mechanical Parameters of the Surrounding Rock  
The physical and mechanical parameters of the surrounding rock are the basis for the theoretical study of underground engineering, engineering design, and construction, and are an important basis for the study of the support structure of the roadway and the stability control of the surrounding rock. According to the research needs, the 2500 transportation roadway of this mine is taken as the research object, and the top and bottom plates of the roadway are core-taken on the spot using a geological drilling machine. The drilled core samples are shown in Figure 3. The samples were sealed with cling film to be processed in the laboratory. All rock samples were cut and polished in the laboratory and finally processed into cylindrical specimens of \(\Phi\)100 mm \(\times\) 150 mm and \(\Phi\)100 mm \(\times\) 50 mm, as shown in Figure 4. Through the uniaxial compressive test, as shown in Figure 5, and shear test, as shown in Figure 6, the basic mechanical  
The mineral composition of rock is the main factor controlling its physical, mechanical, and hydro-physical properties, and is also an important basis for evaluating the water-bearing (isolation) performance and anti-mining deformation capacity of soft layer soil. Therefore, it is essential to determine and analyze the mineral composition of silty sandy rock and soil.  
In order to analyze the internal structural characteristics of the specimens more intuitively, electron microscope scanning tests were carried out on the mudstone and sandstone samples, respectively, and the instrument model used for the SEM analysis was the Czech Republic: TESCAN MIRA LMS. The results of the scans are shown in Figures 7 and 8. By  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Rock Type**} & **Gravitational Density** & **Modulus of Elasticity** & **Compressive Strength** & **Tensile Strength** & **Poisson’s Ratio** & **Angle of Internal Friction** & **Cohesive Force** \\  & **\(\gamma\) (KN/m3)** & **\(E\) (Mpa)** & \(\sigma_{c}\) (Mpa) & \(\sigma_{t}\) (Mpa) & \(\mu\) & **\(\varphi\) (\({}^{\circ}\))** & **\(c\) (Mpa)** \\ \hline Sand stone & 25.5 & 12,139 & 75.65 & 8.57 & 0.26 & 33.21 & 3.96 \\ Mud stone & 22.4 & 9055 & 44.35 & 4.05 & 0.28 & 28.35 & 2.24 \\ Coal & 14.05 & 3525 & 43.21 & 0.85 & 0.015 & 30.21 & 1.21 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Physical and mechanical parameters of the surrounding rock.  
Figure 5: Uniaxial compression test.  
Figure 6: Shear test.  
observing the test results, it can be seen that the mudstone specimen is gray-black and blocky, with a relatively uniform particle size distribution, but the inter-grains are soft, with poor particle cementation and a relatively high amount of powdery sand grain. They also contain a large amount of quartz, feldspar, ilmenite, black mica, and a ilmenite mixing layer, as well as a small amount of iron oxides, calcite, monazite, barite, and other minerals. The sandstone specimen particles' gravel diameter is small and gray-black, with good homogeneity and good cementation between the cement. In addition to the individual gravel sand gravel with an unequal gravel diameter, the other main mineral components are quartz, a montmorillonite or ilmenite mixed layer, chlorite, ilmenite, and so on.