Span Length

70′ 82′ 94′ 106′ 118′ 130′ 142′ Span Length BI51 70′ - 110′ BI63 85′ - 130′ BI75 105′ - 140′

Section Properties (gross)

Product NameDepth (in)Area (in2)Yb (in4)Ixx (in4)Iyy (in4)PLF @ 165

Product Information

The Bulb I (BI) girder is a standard variation of the Bulb-T girder. Use the BI shape only when it has benefits over a Bulb-T girder. Since the BI girder have a narrower top flange, it requires less concrete build-up than a Bulb-T. Therefore bridges with high super elevations (generally, greater than 7%) may want to consider the BI girder.


Standard Design Options

  • Forming and Diaphragm Inserts.
  • Adjust web thickness to accommodate post-tensioning (for spliced girders). For such cases increase the web thickness from 6″ to 7.5″
  • Cast in inserts or hole for diagraph reinforcing
  • Cast in inserts for mounting utility brackets
  • Top flange/web holes for mounting deck forming brackets

3D Viewer

3D Viewer Tools


  • 3D Viewer Functions:
  • Move, Span, Zoom Assemblies
  • Isolate Single Components in View
  • Explode Assembly Single Components
  • Use Markup to Sketch Details
  • General Measurements for Concept
  • Print Views

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