Study on undercrossing existing metro station and bridge with extending footings construction scheme of metro

Constrained by Beijing subway line 2 Chaoyangmen station, the Chaoyangmen-Dongdaqiao interval tunnel of Beijing metro line 6 is subdivided into the eastern burying mining part, the western burying mining part and the connecting tunnels part. This interval tunnel closes to the existing Chaoyangmen subway station and Chaoyangmen Bridge. The connecting tunnels with small clear space are shallow-buried and near the existing structures, the construction is hard and high-risk. In order to coordinate with construction, different construction methods are simulated by three-dimensional finite element software MIDAS-GTS. Based on the analysis, an optimized construction scheme that excavate from both sides of the tunnel and make horizontal jet-grouting piles from both sides of the existing station is proposed. The research results can provide theoretical support for the design and construction of the tunnel.