×
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

Deflection for visibility

Deflection for visibility

Deflection for visibility

(OP)
Hi,
I have a 10-ft beam span under uniform loading, supporting visual screens (projection similar to monitors). Deflection is at L/1000 and I want to know if this will be visible to end users at 20~40 ft away. For non building structures without specific deflection limit, what would be typial slpe that will be bsible to others? Thank you.

RE: Deflection for visibility

Normal limit for visual deflection in buildings is L/250. At L/1000 I would doubt that you could see the deflection from this distance.

Do the screen suppliers give recommended deflection limits?

RE: Deflection for visibility

I suggest a very tight deflection spec if the load vibrates.

RE: Deflection for visibility

As BUGGAR said, if the load is applied or removed rapidly then you will likely have a more obvious effect than if it was slowly applied and removed.

I'd go for L/800 which is what bridges are limited to in AASHTO.

Professional and Structural Engineer (ME, NH, MA)
American Concrete Industries
www.americanconcrete.com

RE: Deflection for visibility

Quote (TehMightyEngineer)

I'd go for L/800 which is what bridges are limited to in AASHTO
What does a bridge deflection have in common with visual screens?

RE: Deflection for visibility

It's a structure subject to rapid loading and unloading that I imagine would scale well to the distance the OP's clients are viewing the monitors and the size of his/her 10 ft beam. Seemed like a good starting point.

Professional and Structural Engineer (ME, NH, MA)
American Concrete Industries
www.americanconcrete.com

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