Raft design for tank

[Anonymous]

Hi,

We are trying to design a concrete slab to support a tank which weighs 200kN using a raft design. I have never used robot before for concrete design so not familiar with how to do it. However I have read the forum and watched some example.

What our aim is to have a model that shows A393 mesh and the results - is it possible someone can show me what is wrong with my model. the results are not what we expect.

Additional questions

1. what is this error

1. as I want A393 mesh I what to turn off all bars however it wont let me save is this correct that I cant save without selecting a bar?

1. When trying to design with mesh I get strange results and when I look at slab reinforcement the lines are shown in the top for both. Why is this showing it like this and cannot it not show bars like the below when designing with loose bars?

1. Even when designing with loose bars the bars are shown top only for both top and btm cases, how do I correct?

If I can ask someone to look at my model to see where I have gone wrong and correct my model would really appreciate.

Thanks

[Anonymous]

Can someone explain how to attach model?

[Simau]

@Anonymous 

Zip your model before attaching it

[Anonymous]

Thanks

Please see file.

[TSOFA]

I think that you should change your SLS combinations to SLS:QPR in order the RC to be checked for deflections and derive the proper reinforcement

"If you select EN 1990 or any National Annex to this code as a load combination code, this list also includes specific 3 types of SLS load combinations (action combinations) distinguished according to EN 1990 Eurocode - Basis of structural design:

• SLS:CHR - Characteristic combinations, used for checking irreversible limit states such as cracking in reinforced concrete.
• SLS:FRE - Frequent combinations, used for checking reversible limit states such as cracking in prestressed concrete.
• SLS:QPR - Quasi-permanent combinations, used for checking long-term effects and the appearance of a structure, such as deflections."

[Simau]

@Anonymous 

To avoid the wraning create some new SLS comb as said by @TSOFA 

In your parameters uncheck this item

Then no problems

[Simau]

Updated model

[TSOFA]

@Simau ,

unfortunately, I have an older version of RSA so I can't check your model, sorry

Is it something that you think that is not right or now you have reasonable results?

[Anonymous]

Hi @Simau  & @TSOFA ,

Thanks for the reply help.

I have made the changes, the error was resolved but the reinforcement is still not working.

I tried to open the model attached but nothing is there I am using 2019 version is that the reason?

Can you save it in this version?

Thanks

Daniel

[Simau]

Hi @Anonymous 

You can open a 2020 file with 2109 version.

Could you share your 2109 file

[Simau]

@Anonymous 

2019 model attached

[TSOFA]

unfortunately I use a 2017 version