Span Length

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

Section Properties (gross)

Product Name Depth (in) Area (in2) Yb (in4) Ixx (in4) Iyy (in4) PLF @ 165
BI51 51" 566 25.2 191444 16303 650
BI63 63" 638 31.1 327551 16519 733
BI75 75" 710 37.1 509572 16735 815
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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.

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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
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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

Need More Info?

We Are Here to Help

 

Have a question, need a budget or detailed schedule?  Knife River sales team is ready to discuss precast solutions for your project.  Reach out to our staff below :

Image's Eric Holje

Eric Holje

Bridge Estimator

phone

(509) 536-3323

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LinkedIn
Image's Sam Jewell

Sam Jewell

Outside Sales Representative

phone

(541) 221-8599

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LinkedIn

Product Family

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