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Concrete Slab Problem - beginner

41 REPLIES 41
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Message 1 of 42
Wioletta_F
886 Views, 41 Replies

Concrete Slab Problem - beginner

Hello,

I'm trying to model concrete flat slab and compare the results to results from different software. I fallowed all guidance I could find but it looks like I'm doing something wrong and my deflections are WAY to big. Can you please help? Where do I start?

 

 

41 REPLIES 41
Message 21 of 42
Wioletta_F
in reply to: Wioletta_F

Hello! I wonder if you could give me some more guidance please? Max deflection is only 15mm (and I know it should be 50mm ish). I run the design of reinforcement (got errors for punching shear) and had a look at long term conditions, stiffness factors etc. But the results are not correct. As I said I'm a beginner, tried to read manuals etc. but don't really know how to fix it. Will be grateful for your advice. And also I can't figure out how to manoeuvre Maps colour scale so that the results are easy to read (everything comes up in the same colour).

Message 22 of 42

The map suggests that the deflection is 0 (has not been calculated). The [possible reasons:

1. No SLS cases used for RC Slab Required Reinforcement calculations

2. Check of deflection not marked in the reinforcement type assigned to the slab

3. Supports in all nodes of the slab so that it doesn't deflect (this happened more than one time in the models I received) Smiley Happy

 

If none of the above I need the model to look at.



Artur Kosakowski
Message 23 of 42
Wioletta_F
in reply to: Wioletta_F

Czesc Artur!

1. First guess correct - didn't put any SLS for required reinforcement

2. Not to sure were to check

3. It deflects now 22mm so I don't think it's a case Smiley Happy

 

As I said above, I'm getting 22mm deflection for long term conditions but it's still half of what is expected. Can you please have a look at the attached file? Thank you very much. I used 7zip as 'normal' zip wouldn't get it under 1.5Mb.

Message 24 of 42
Wioletta_F
in reply to: Wioletta_F

Sorry, my zip is more than 1.5Mb and when I use 7zip the file is not going trough, what can I do?

Message 25 of 42
Rafal.Gaweda
in reply to: Wioletta_F

winrar to compress or www.wetransfer.com then paste the link to file in post



Rafal Gaweda
Message 26 of 42
Wioletta_F
in reply to: Wioletta_F

Looks like rar is not allowed extension (message comes up) and I can't use wetransfer (company policy). Is there any other way I can send it to you, please?

Message 27 of 42
Wioletta_F
in reply to: Wioletta_F

My colleague managed to compress the file even more. Please find attached and sorry for the confusion.

Message 28 of 42
Rafal.Gaweda
in reply to: Wioletta_F

change rar extension (text) onto ra_ or zip or anything allowed



Rafal Gaweda
Message 29 of 42
Rafal.Gaweda
in reply to: Wioletta_F

According to data in model max RC deflection is ~23mm

 

23.jpg



Rafal Gaweda
Message 30 of 42
Rafal.Gaweda
in reply to: Rafal.Gaweda

After verification with stiffeness update 52mm

 

52.jpg



Rafal Gaweda
Message 31 of 42
Message 32 of 42

That's brilliant! Thank you. Only when I run the design deflection is 42mm and not 52mm. I noticed that when running 'required reinforcement task' the message 'required types are not acribes to SLS combination, calculation may not be correct' comes up. Could that be the reason?

 

P.S. For some reason I can not open the attached link...

Message 33 of 42
Wioletta_F
in reply to: Wioletta_F

Forgot to attach... sorry..

Message 34 of 42
Rafal.Gaweda
in reply to: Wioletta_F

PLease update your version with Service Pack 5 for ARSA 2012.

 

2505.jpg



Rafal Gaweda
Message 35 of 42
Rafal.Gaweda
in reply to: Wioletta_F

 I noticed that when running 'required reinforcement task' the message 'required types are not acribes to SLS combination, calculation may not be correct' 

 


SLS combinations for RC Desing should be SLS:QPR (quasipermanent) or SLS:FRE (frequent)

 

ct.jpg



Rafal Gaweda
Message 36 of 42

Thank you. Will change and check deflections again. Have a good weekend and I'm sure I will be back next week Smiley Happy

Message 37 of 42

Hello!

I'm trying to tidy the design - had to add some walls (linear supports) etc. While deflection is OK, moments are just way out of what I think they should be. Basically we've got the design done in different software... Could you please have a look at the attached and suggest where I went wrong again? And thank you very much for great support so far.

Message 38 of 42
Rafal.Gaweda
in reply to: Wioletta_F

Pani Wioletto,

 

Troche wiecej szczegolow. Gdzie i czego Pani sie spodziewa, ktory przypadek itd...



Rafal Gaweda
Message 39 of 42
Wioletta_F
in reply to: Rafal.Gaweda

Panie Rafale,

zestawilam przykladowe wyniki na zalaczonym pdf-ie. Grubosc plyty jest taka sama, obciazenia takze. Jak juz wczesniej napisalam ugiecia pod dlugotrwalym obciazeniem sa zblizone (53mm w Orion i 55mm w Robocie). Niestety momenty sa rozne. Nie za bardzo wiem jak do tego podejsc, bo analiza nie wykazuje zadnych bledow. Czy lokalne zageszczenie siatki na podporami 'wygladziloby' wykres momentow? No i w przesle roznica jest duza. Bardzo prosze o jakies sugestie i jeszcze raz dziekuje za pomoc.

Message 40 of 42
Rafal.Gaweda
in reply to: Wioletta_F

Czy Orion to program MESowski czy tez liczy sie tam pasmo (np 1m szerokosci plyty) w analogii belkowej?



Rafal Gaweda

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