×
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

Curtain Wall Deflection
2

Curtain Wall Deflection

Curtain Wall Deflection

(OP)
What horizontal, deflection criteria is recommended for exterior, glass, curtain walls to resist lateral wind forces?  L/600? 480? 360?

On a slight tangent, what would you recommend for the following:  (All due to lateral wind forces)

-Exterior structural concrete masonry also supporting gravity loads.

-Exterior concrete or brick masonry veneer.

RE: Curtain Wall Deflection

Usually L/600 is reserved for masonry or veneer, curtain wall, L/360 should be adequate, however they might have criterion to follow.

RE: Curtain Wall Deflection

almost all of the aluminum curtain walls that I have designed deflection has been specified to be L/175 or 3/4" whichever is less

RE: Curtain Wall Deflection

AISC's Steel Design Guide #3, "Serviceability Design Considerations", has L/240 listed as a Deflection Limit for wind forces in Table 1 for Exterior Walls with brittle finishes.

RE: Curtain Wall Deflection

I design my curtain walls for L/360 generally unless they support brick veneer which gets a deflection criterion of L/600.  

RE: Curtain Wall Deflection

What exactly is "Empirical Design of masonry" as per MBC 2003? If you use the NCMA software for a masonry load bearign wall design, would you consider it as a special design or an empirical design?

RE: Curtain Wall Deflection

2
For glass and al. curtain wall, currently, the most often used deflection criteria is l/175 w/ 3/4" max for spans less than 13'-6" and l/340+1/4" for spans greater than 13'-6".  The old l/175 , 3/4" max was an old window criteria intended for use w/ single lites.  It is too conservative for modern curtian wall design, especially when coupled with C&C wind pressures.

RE: Curtain Wall Deflection

For out of plane, I would use L/180 or so for curtain wall (more strict depending on the finish), l/300 or so for cmu and brick. I think a lot of people use different amounts. I usually check total deflection as well as the ratio.

You could multiply the wind load by 0.7 in IBC 2000 for checking deflections under C&C , I haven't checked if you still can in 2003.

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