Abstract:

Taking the construction of the smallspaced group tunnels of Xuanwumen Station on No. 4 Line of Beijing Metro as an example, the author optimizes the construction methods, excavation sequences, distances among excavation faces of the pilot tunnels and bench lengths by orthogonal tests and numerical simulations. The author also analyzes the ground surface settlement caused by construction of group tunnels, as well as the mutual influence among the group tunnels. Reasonable construction scheme is determined on basis of the analysis and study results. The paper can provide reference for future studies.

Key words: small spacing  , group tunnels construction scheme optimization  , orthogonal test  , numerical simulation  , ground surface settlement