×
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

Return Period on Thermal Loads

Return Period on Thermal Loads

Return Period on Thermal Loads

(OP)
Does anyone in this forum know what the design return period is/should be for thermal induced loads, or deflections?  
I have a problem that many of you may relate to.  I am designing a large warehouse 300,000 sq. ft, that has an expansion joint in the middle.  The research report that I am using, "Expansion Joints in Buildings - Technical Report No. 65" by the Standing Commitee on Structural Engineering (a subcomittee of the National Research Council), cites a design temperature with a 100 year return period for both cold and hot maximums.  
If I am designing in BOCA '96, based on ASCE 7-95 I have to include thermal loads in the load combination D+S+T (seismic controls and deflections are small so D+S+W+T does not control).  In ASCE 7-95 the design earthquake is 2/3 of 10% in 50 years, the design wind is 2% in 50 years; what thermal load should I use?
I say this because we recently had a building sustain damage due thermal expansion creating more eccentricity on a connection than it was designed for.  The contractor substituted weld all around on a seat for just welds on the vertical sides.  With the increased eccentricity of the thermal expansion the welds have started to un-zip.  So any guidence would be greatly appreciated.
thanks

RE: Return Period on Thermal Loads

The answer to your question lies in the statistical data and elaboration leading to the expansion and shortening thermal ranges mandated in your code for the application. I have given a look to a publication in Spain but also omits that. In the absence of data for any particular site, I would use the values of return for wind, since circulation of the atmosphere is in its way related to cycles of solar radiation, and these to temperatures.

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