The Investigation of Stability of Tunnels and Settlements with Centrifuge Modeling

Abstract

In most of the larger cities underground transportation systems have been gettingdesired. Such systems are constructed in urban areas and involve a tunnel, especially in softground and in shallow zones.One of major concerns for tunneling operations in urban area is the effect onneighboring buildings, because the tunneling operation and near structures highly interacteach other. Whatever the used construction method is, the excavation of a tunnel causesdisplacement around the opening and may expand towards the ground surface. Thedislocations of the buildings interact with the ground movement, and the rigidity of existingstructures will promote reduction of the magnitude of displacements induced by tunneling.In this investigation, to determine displacements induced by tunneling, the centrifugemodeling was used. The small scale centrifuge model provided dependable information aboutthe face collapse of a shallow tunnel. A required support pressure for shield driven tunnels insoft materials, and the ground deformations along the longitudinal section of the tunnelmodel, can be identified by simulating a loss of tunnel face stability.