×
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

Long term deflection concrete slab studies.

Long term deflection concrete slab studies.

Long term deflection concrete slab studies.

(OP)
Does anyone know of any published studies for long term deflection recordings of concrete slabs. The only study i know of is this one by Ian Gilbert & Co?

R407: An experimental study of reinforced concrete flat slabs under sustained service loads

http://www.civeng.unsw.edu.au/staff/ian_gilbert/  

Arguing with an engineer is like wrestling with a pig in mud. After a while you realize that they like it

RE: Long term deflection concrete slab studies.

rowingengineer - watch out for the next issue of Concrete in Australia.  The theme is deflections and there will be a number of technical papers on the subject.

Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/
 

RE: Long term deflection concrete slab studies.

(OP)
Doug,
Thanks for the heads up, also thanks for the reference, was able to down load it, hopefully they go back and complete the survey in a few years again, to really get some good information.

Ishvaaag,
Thankyou for the reference, unfortunately I am an excel guy so couldn't make use of your Mathcad sheet.
 

Arguing with an engineer is like wrestling with a pig in mud. After a while you realize that they like it

RE: Long term deflection concrete slab studies.

There is the slab deflection in our office that I have been meaning to study but never got around to doing. I was going to run a string-line to it so I can measure the deflections and calculate estimated deflections using the theory which Prof Ian Gilbert writes about. The unknowns will be the time that the slab was first loaded (say 14 days) and the permanent loading (1.20kPa / 25psf). That will be a form of study when completed.

thread744-265955: Long Term Deflection & Compression Reinforcing

RE: Long term deflection concrete slab studies.


The first two go together as the paper by Taylor and Heinman is from the syllabus.

http://www.ce.memphis.edu/6136/PDF_notes/syllabus_06.pdf

This is the paper referenced in the syllabus. You might be able to get this paper from the Linda Hall Library.

(J.P. Taylor and J.L Heiman, "Long Term Deflection of Reinforced Concrete Flat Slabs and Plates," American Concrete Institute Journal, November 1977, pp. 556-561.)            

These are just two that popped up along with the above.

http://www.adaptsoft.com/resources/ADAPT_TN292_floor_deflection.pdf

http://www.thomastelford.com/journals/DocumentLibrary/STBU1580106.pdf


I found the Taylor and Heinman paper but it was in Spanish

 
 
 

RE: Long term deflection concrete slab studies.

Strictly anecdotal information, but the 5 foot (60 inch) span, 4 inch thick drain culvert slabs covering cleaning access ports in my neighborhood have substantially slumped in only 40 years (early 70's until 2010) from gravity alone ...  

Sure, they are probably non-reinforced (improperly) , and a non-critical application, but very ugly results.    

RE: Long term deflection concrete slab studies.

(OP)
unclesyd,
the paper by taylor was in the right ball park, the paper he wrote as teh basis for the paper you suggest was a hiome run.

thanks

asixth,
Let us know the results of your study, will be interesting to see.

Arguing with an engineer is like wrestling with a pig in mud. After a while you realize that they like it

RE: Long term deflection concrete slab studies.

Your welcome and appreciate the heads up.

Was just hoping to repay you for hijacking your thread.

RE: Long term deflection concrete slab studies.

We had a case, back in the late sixties that got some attention. An office building, concrete floor on metal deck, composite with the beams but not the girders. The building was not occupied for two years, at which time, cracks started to appear along the girders. A review of the design said it was okay but creep had allowed the beams to deflect more, causing the beam ends to rotate and stretch the concrete above the girder.

After that, I reinforced for the fixed end moment over the girders.

Michael.
Timing has a lot to do with the outcome of a rain dance.

RE: Long term deflection concrete slab studies.

(OP)
It is amazing how many eye sores can be hidden under carpet.  

Arguing with an engineer is like wrestling with a pig in mud. After a while you realize that they like it

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