×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

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!
  • Students Click Here

*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.

Students Click Here

Jobs

Knee Brace as a substitute for X-Bracing

Knee Brace as a substitute for X-Bracing

Knee Brace as a substitute for X-Bracing

(OP)
I am designing a rectangular platform for an industrial application. All four bays in the vertical plane were provided with diagonal x-bracing. Due to clearance requirements the diagonal x-bracing is not acceptable. Can the x-bracing be replaced with knee braces? Or are knee braces together with rigid moment connections required? Thanks in advance.

RE: Knee Brace as a substitute for X-Bracing

I have done this before where equipment shelters needed clearance, so x-bracing was out.  Knee braces should work well unless you are in an extremely high wind area.

RE: Knee Brace as a substitute for X-Bracing

Knee braces are common for structures with a small 'racking' force. Your frame may become more flexible because of the eccentricity of the bracing.

RE: Knee Brace as a substitute for X-Bracing

You are switching from concentrically braced frames to knee braced frames (ordinary moment frames in AISC 341-05) so there are different seismic limitations under this document. I don't what code you are under.  

RE: Knee Brace as a substitute for X-Bracing

Yes, knee braces are acceptable and practical.  You may need stiffer columns and/or beams to limit lateral deflection.  X-braces are used because they are more efficient that knee braces, but knee braces are common.  Be sure to check the columns and beams for the added moment you will impose on them.  Also, we typically round the code required lateral load up to be conservative.

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!


Resources