closely-spaced twin tube tunnel

Curved immersed tube tunnel

draft tube tunnel

immersted tube tunnel

Submerged tube tunnel

sunken tube tunnel

tunnel tube wave

twin tube tunnel

tube wind tunnel

Heat Exchange Tube and Tube Sheet

Tube in Tube Structure

Tube to Tube Sheet

Tube-in-tube

welding between heat exchanging tube and tube sheet

Tube—in—tube

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