Settlement Analysis and Technique Measures for Double-line Tunnel Crossing Bridge Piles

The DK30+820—DK30+855 segment of Matsuyama Lake Tunnel passes the piles of Shida Highway Bridge.To ensure the safe operation of Matsuyama Lake Avenue and the highway bridge,the surface settlement and the bridge pile settlement due to the excavation of the tunnel were simulated and calculated assuming CD excavation method.Major technical control measures and monitoring issues were proposed.The monitoring results show that the combined applications of control measures in the tunnel and strengthening measures outside the tunnel with sleeve-valve-pipe grouting was successful.