A compact blowout model for shallow tunnelling in soft soils

Tunnelling in soft soil conditions, especially with a shallow overburden, faces the risk of face instability due to blowout. Although several blowout models have been proposed to estimate the blowout pressure, mostly based on limit analysis or limit equilibrium, there is a significant gap between the allowable blowout pressures predicted by...

Structural analysis for shallow tunnels in soft soils

Generally, studies on structural design for bored tunnels focus on moderate to deep tunnels (cover-to-diameter ratio C/D ≥ 2). Such tunnel design methods cannot be used for shallow-situated bored tunnels because the influence of buoyancy is discounted, and actual loads on the tunnel lining are not taken into account properly. This paper...

Volume loss in shallow tunnelling