Yield Line Analysis of Slabs 2

[abusementpark]

Does anyone actually use this in practice?

I have been learning about it recently in an graduate-level advanced concrete class, and it is very interesting. However, I am wondering if there is anyone out there who uses it. It seems like there may be some hurdles to applying it in practice.

 

[JedClampett]

I've used it. I wouldn't design with it, but it's good for checking an existing slab, originally designed as one-way, for an increased load. It's not going to give you n huge increase, but it might give enough for a changed use.

 

[dik]

The first engineering work I ever did was supervising a load test on a concrete gym floor where the top reinforcing mats collapsed onto the bottom reinforcing steel. Failure produced a classic yield line pattern. The failure occurred in a technical institute and there was a structural group that I invited down to see the failure. The contractor was not impressed that I marked the failure pattern out in permanent marker.

I used yield line to analyze a plate about 40 years ago (they had markers back then, too) where the columns were offset by half a bay.

I tried attaching a file on yield line (source unknown) but it is over 5 meg... and too large, I guess.

Dik

 

[ishvaaag]

Really one can easily. One of the more common books on reinforced concrete here, the Montoya-Meseguer-Morán has tabulations for cases of slab I think to remember based in the yield line approach. Was quite used prior to FEM, the 70's and 80's. I lately have met this thing mainly as the one of the limit capacities for a point load on a slab, as a function of standing flexural reinforcement. And likely when used cooked details or formulations for steel plates we are also using yield line approach.

http://civilearth.wordpress.com/2009/01/23/practical-yield-line-design/

 

[abusementpark]

Thanks for responses, guys.

Dik,

Have you tried zipping the file before posting it?


ishvaaag,

Are you supposed to be able to download a publication from that link? I tried clicking the download link but it takes me elsewhere.

 

[ishvaaag]

Hmmm you are right. The question is that I have this pdf. So from some place I downloaded it sometime ago. Will try to find the source and post.

 

[ishvaaag]

Try this one

http://www.brmca.org.uk/downloads/PYLD240603a.pdf

 

[abusementpark]

ishvaaag,

Thanks!

 

[Lion06]

I've never done it for concrete. That being said, I've used the analysis procedure from my concrete text to check cap plates for an existing building because I couldn't find any relevant info for steel plates.

 

[dik]

Thanks for the link, Ishvaaag... that's the publication I was trying to upload. Often *.pdf documents are well compressed.

Dik

 

[dik]

The caution with yieldline is that it gives you a failure loading and pattern... hopefully it is the one with the proper minimised loading... it gives you no information about deflections or cracking to achieve that end...

Dik

 

[rowingengineer]

I use it for foundations (wind turbine foundations normally) all the time. However for deflection controlled designs it isn't the best.

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