Blue Line tunnel diameter

Tallguy

Active Member
Joined
May 2, 2018
Messages
886
Reaction score
459
Does anyone know the minimum diameter a BL train might operate in?
 
Does anyone know the minimum diameter a BL train might operate in?

I don't know the diameter of the tunnels, but they are the shortest cars in length that operate on ANY of the other lines in the system. But they are all 6-car trains like the Red & Orange Lines. :)
 
Does anyone know the minimum diameter a BL train might operate in?
BL cars are 9-1/4 feet wide. x2 side-by-side that's 18-1/2 feet. Add the clearance envelope to that and you probably get to a practical minimum operating width of 22 ft. Add the tunnel walls and it's an under-street minimum of no less than 25 feet.

Though the design minimums for new construction have been Red Line-dimension tunnels for 110 years now.
 
Also remember you need a walkway in each tunnel of maybe 3-4 feet.
 
So, a single track TBM (circular) tunnel would need to be....18ft? 16ft? 17ft? The car is ....12ft 9in tall?
 

Back
Top