asymmetric tunnel barrier
diversion tunnel and spillway tunnel
option of separate highway tunnel and Metro tunnel
railway tunnel under crossing the highway tunnel
Shield Tunnel and Rock Tunnel
water tunnel and salt tunnel
1600℃ energy-saving gas tunnel kiln
3D monitoring of tunnel slope deformation
a little spacing tunnel
a shallow mined large-span crossover tunnel
abrupt changes in the cross-sectional area of a tunnel
Access Tunnel
隧道通道
刷引线
人员进出地道
辅助隧洞
引水隧洞
交通隧洞
进口隧道
横洞
通道
隧道
Access Tunnel to Powerhouse