Innerbelt Bridge

Largest Steel Girders for the Innerbelt Bridge Roll into Town
Fact Sheet:

What Are They?
  • Delta girders are named for the triangular shape they form once they are assembled.  “Delta” is the fourth letter of the Greek alphabet and resembles a triangle.
  • Each Delta girder assembly is made up of six (6) steel parts; two Knuckles, two Delta Legs, one top girder and one “V.”  Each Delta assembly is connected to the next with another straight girder (not shown in the image below).
  • The piece delivered today is the Knuckle –it connects the Delta Legs with the top girders.
  • In general, the Knuckle girders are 67 feet long, 8 feet high at the narrowest end and 18 feet high at the widest end.
  • There will be 80 of these Knuckle girders used on the main bridge section.
  • Each Knuckle weighs approximately 100,000 pounds – that’s about 8 million pounds of steel in the Knuckles alone.
Getting Them Here:
  • The truck that delivers them will be carrying a load that is 18 feet wide; it requires a special permit, escorted by Highway Patrol since it takes up two (2) lanes of traffic.
  • The streets along the delivery path have to be closed briefly while the truck is passing through, but they are opened as soon as the truck has passed.
  • Shipments of steel will continue to be made through next spring. 
Where They’re Made:
  • The huge girders are being fabricated by High Steel Structures, Inc. in Pennsylvania. 
  • As with all steel used on the new Innerbelt Bridge – and all ODOT projects – it’s made in America!    
Steel Bridge Parts: