Figure 7
From: FEM analysis of a new three-way drainage and pressure reduction system for road tunnels
Secondary lining external water pressure cloud: (a) No drainage; (b) Conventional drainage; (c) 2 reverse drains; (d) 4 reverse drains; (e) 8 reverse drains; (f) 16 reverse drains; (g) 32 reverse drains; (h) Reverse drain.
