## 3 Example Test and Result Analysis  
### Test Environment Analysis  
The soft rock tunnel of the expressway from Yunxian to Lincang in Yunnan Province was the research object; the total length of the soft rock tunnel is about 10.2 km. The tunnel is designed as a left- and right-separated, two-hole, one-way, two-lane tunnel. The starting and ending distance of the left side of the tunnel is ZK12 + 600-ZK22 + 835, with a total length of 10,235 m. The starting and ending distance of the right side of the tunnel is YK12 + 620-YK22 + 830, with a total length of 10,210 m. The tunnel area elevation is 1197.6-2525.3 m, the design elevation of the tunnel bottom is 1212.38-1394.67 m, and the elevation difference between the entrance and exit of the tunnel is about 1322 m. The tunnel is situated in a high and middle mountain weathering and denudation landform area. The tunnel body in the tunnel area is precipitous and steep, and the surface vegetation is prosperous and dense, dominated by shrubbery, a walnut forest, and a spruce forest. The tunnel lining structure is shown in Figure 1.  
According to the results of geological surveys and drilling, the stratum lithology of the tunnel cross-section includes Quaternary diluvium, Quaternary debris flow accumulation, Quaternary alluvium and diluvium, Lower Proterozoic Lancang Group schist, Jurassic stratum Huakaizuo Formation lower glutenite, and Yanshanian volcanic rock biotite granite [24]. In the inverted arch failure K13 + 060-K13 + 100 section, the rock mass is highly weathered; the lithology is mainly strongly weathered granite and partially granitic schist, with well-developed fissures; and the rock mass has a relatively broken blocky structure. The rock mass of the K13 + 100-K13 + 170 section is highly weathered. The lithology is moderately weathered granitic schist. The rock mass is relatively broken and has a massive structure, overlying the Quaternary slope eluvial brown-yellow gravel and underlying the Yanshanian granite. The lithology within the mud and water inrush (mileage K13 + 612) section is mainly intensely weathered granitic schist and local granite. The rock mass is broken in a fragmented block structure. The fissure water is relatively developed with a strong water yield and poor stability of the surrounding rock. It is overlaid with Quaternary slope eluvial brown-yellow gravel and underlaid by Yanshanian granite. This area has abundant rainfall, developed surface water bodies, and high groundwater levels. The hydraulic connection between the surface water and the groundwater is closely complementary. In the fracture zone development area, the net reserves and regulation reserves of groundwater are relatively rich, and tunnel geological disasters such as collapses, mud inrush, water inrush, and geothermal disasters are prone to occur. The tunnel section is rich in groundwater resources, which can be divided into pore water and fissure water according to the characteristics of water-bearing media. Influenced and controlled by regional faults, the following water diversion structure has developed:  
1. [label=(0)]
2. Pore water  
Pore water is mainly distributed in the form of pore phreatic water in the Quaternary loose accumulation layer. The water volume is small, its location is high, and the water level is altered by seasonal precipitation. It is recharged by infiltration of atmospheric precipitation and discharged to low-lying areas or the surface in the form of springs. Due to the large seepage area of bedrock fissure water, the pore water supply is mainly rainfall. 3. [label=(0)]
4. Fissure water  
The bedrock fissure water in this tunnel section is mainly in the joint fissures, structural fissures, weathering fissures and diagenetic fissures of granitic schists and granites, all of which are tensile fissures that cross each other. They have a good uniformity and openness, forming a network of runoff complementary systems, water storage systems and drainage systems and receiving infiltration recharge from atmospheric precipitation.