Deformation Control of the Existing Medium-Low-Speed Maglev Metro Viaduct over a Double-Line Bored Tunnel

Taking a double-line underground excavation subway tunnel underneath the medium-low-speed Maglev bridge section of the Beijing S1 Metro line as a project reference, the deformation control index of the Maglev metro bridge and track panel was studied using numerical simulation and data monitoring, under the conditions of deep-hole grouting measures for the soil layer around the excavation tunnel and active lifting for the superstructure of the viaduct. The results of the numerical simulation show that the maximum deformation value of the pier is −1.73 mm and the maximum vertical deformation value of the Maglev rail track is −1.56 mm. Monitoring shows that the maximum vertical deformation value of the magnetic levitation rail is −1.25 mm and the deformation is within the allowable range. Both numerical simulation and field monitoring results reflect the deformation trend of existing structures; the deep-hole grouting measures taken to strengthen the soil layer around the tunnel and the upper structure of the active roof elevation frame can effectively control the deformation of the existing structure. The study can provide guidance and reference for similar projects.