Calculation Model and Influencing Factors of Surrounding Rock Loosening Pressure for Tunnel in Fold Zone

Figure 8

Relationship between friction angle and loose pressure (q). 1—k = 0.05; 2—k = 0.10; 3—k = 0.15; 4—k = 0.20; 5—k = 0.25; 6—k = 0.30.