Ground Settlements due to Construction of Triplet Tunnels with Different Construction Arrangements

Figure 6

(a) Twin tunnels (u = 0.55D) in vertical configuration (dimensions in cm). (b) Settlement trough of vertical twin tunnels (u = 0.55D). (c) Displacement contours of vertical twin tunnels (top constructed first). (d) Displacement contours of vertical twin tunnels (bottom constructed first).

(a)

(b)

(c)

(d)