Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.


Beams and girders

Beams and girders

Is there any difference between the words "beam" and "girder" ?

Alessio Spigarelli
Structural Engineer

RE: Beams and girders

Typically a girder is larger than a beam, or may support several beams.

RE: Beams and girders

I use the term "girder" to describe a member that has other members framing into it, and the term "beam" to describe a member that supports only decking or sheathing, with no other members framing into it.


RE: Beams and girders

The way that I was taught in school and now in professional practice is that:

A girder is a memeber that is in the floor system and has other members tying into the side of it.

A beam is a member that is dropped or below the floor system and has members bearing on top of it.

RE: Beams and girders

In the steel bridge world, they often use "girder" to mean "built-up plate girder" and "beam" to mean "rolled section".


Eng-Tips policies:  FAQ731-376

RE: Beams and girders

In structural mechanics, a beam is a virtual device which can only resist bending. A girder also resists bending but also has some torsional resistance. I vote for Keysol's definition.

RE: Beams and girders

But a beam element in FEA has torsional rigidity, so I think your definition is rather restricted. I can't remember  Shigley, Timoshenko or Roark making that distinction.

To me a girder has an implication of being fabricated from sub-components, as HgTX suggests.


Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close