Abstract:
The influence of double-line shield tunnel of urban rail transit under railway bed and close-distance side-crossing railway frame bridge was explored, and the protection measures of railway were analyzed to ensure the safety of railway operation.This paper took the under-passing railway trunk lines in the Shilipu-Hangang Tunnel Section of Wuhan Metro Line 12 as an example, the influence range of shield construction on railway bed and the protection effect of ground reinforcement on railway bed were explored by the method of theoretical analysis+numerical simulation.The results demonstrated that: ① The main influence range of double-line shield tunnel under-passing railway bed was about 77 m.The general influence area (about 20 m) was located on both sides of the main influence area, and the slight influence area was located about 30 m outside the general influence area.② The maximum deformation of railway bed and frame bridge after shield tunneling was 2.78 mm and 2.27 mm respectively after ground grouting reinforcement.Ground grouting could effectively control the deformation of railway bed and surrounding frame bridge.③ In grouting reinforcement construction, attention should be paid to the foundation on both sides of the railway bed and the soil between the frame bridge and the shield tunnel.