Analysis on ground surface deformation induced by the subway double tunnels construction

Abstract

The relative position change of metro double tunnels and construction of the sequence will induce the surface deformation and the interaction of the tunnel lining. It is more concerned about these issues in tunnel design. In this paper, It is the main purposes to analyze the metro double tunnels surface deformation which induced by the position changes of new construction double and the sequence of construction. From the numerical simulating results, in order to reduce surface deformation and ensure the structural safety over the subway tunnel, it should try to make double-tunnels at the same horizontal plane in design. If the double tunnels could not be located at the same horizontal plane, the double-hole tunnel construction sequence of the deformation of the surface subsidence effects are obvious it is obvious that the double tunnels construction sequence differently make the deformation of the surface subsidence. To reduce the deformation of the surface subsidence, it should be first excavated the shallow tunnels and then excavated the tunnel buried deeply. The ideal distance of the double tunnels center is greater than 4 times the tunnel diameter. It can make the surface subsidence reduce to the minimum during the metro tunnel construction.