Complex Analytical Study of the Stability of Tunnel-Surrounding Rock in a Layered Jointed Rock Mass

Figure 3

Conformal mapping for the tunnel. (a) Fourth-class highway two-lane tunnel (20 km/h). (b) Third-class highway two-lane tunnel (40 km/h). (c) Second-class highway two-lane tunnel (80 km/h). (d) First-class highway two-lane tunnel (100 km/h). (e) First-class highway three-lane tunnel (120 km/h).

(a)

(b)

(c)

(d)

(e)