×
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

Billboard sign deflection consideration

Billboard sign deflection consideration

Billboard sign deflection consideration

(OP)
I am design a 70' high billboard sign, and I am wondering if anyone knows what the deflection limit at tip of the pole.

Thanks.

RE: Billboard sign deflection consideration

I am not aware of any deflection requirements for a billboard, but here are my thoughts. If it does deflect, it probably won't be noticeable to the passerby at that height. As long as the deflection does not contribute to significant P-delta affects, the deflection should not matter. I would expect the various strength limit states to control (flexure, shear, etc).

RE: Billboard sign deflection consideration

If there is no code to guide you, I would size it based on stress and then just make a reasonable judgement call on deflection. maybe 6" is ok?

RE: Billboard sign deflection consideration

I would think vibration might be a bigger consideration than just static deflection (and assume that's the fatigue item mentioned above)- who's reading a billboard in a hurricane, anyway?

RE: Billboard sign deflection consideration

I'd be more concerned about dynamics and fatigue.

Dik

RE: Billboard sign deflection consideration

Treat it like a high-level luminaire, and use AASHTO code limits to design it.
Dave

Thaidavid

RE: Billboard sign deflection consideration

I agree with Thaidavid40. Start with Section 2 of the AASHTO Standard Specs for Structural Supports for Highway Signs, Luminaires and Traffic Signals. Pay attention to the new fatigue section - depending upon what your columns are. Read Section 10.4.2.1.

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