Model warnings

[Anonymous]

I have 3 warning after calculated a 3 storey RC frame:

-incoherent mesh on edges

-cohesion of the calculation model has been provided by definition of kinematic constraints in incoherent points of finite element mesh

-linear load as not been applied to a pannel

I have tryed to follow other post and change the mesh settings but it is even worse.

I have attached the model file:

http://www.filemail.com/t/36154234cbb54dc9834ae45ca2b1d2d6

thank you

[Rafal.Gaweda]

---

Franco

Thanks for your reply. However, the steel columns do not line up with the concrete columns below.

I appreciate any sketch you can publish because I do not understand your thoughts.

The slab at +9.0 is required to transfer the loads.

Can rigid links be applied to the actual floor slab?

Riigid links connects nodes. On the screen shot above you see concrete column (lower level bars) top nodes on the level of slab, slab is meshed, rigid links are applied to top_column_node=slab_node and bottom node of steel (upper level) columns

[Anonymous]

I have another problem with the slab provided reinforcement.

I have manually defined the zones but after the verification I have this error: "User defined zones do not cover all regions in which reinforcement is required".

I am sure I had covered all the regions, in all the 4 directions.

Thank you

[Artur.Kosakowski]

Try to define the zones slightly outside the slab's shape. 

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[Anonymous]

Thank you, you solved my problem with reinforcements.

Now I have created an RC slab with some point loads and springs supports.

I have 2 problems:

1) Robot auto-deletes the nodes I have used for apply the loads on the slabs.
2) I am not happy with the reactions on the springs. for example in the picture attached you can see a point load of -379.52 and the springs reactions both around 70kN.
Have I applied the load in the right way on the slab? I have attached the model at the end of the post.

http://www.filemail.com/d/hkaoupwpzcpvsld

Thank you

[Artur.Kosakowski]

1) Robot auto-deletes the nodes I have used for apply the loads on the slabs.

When this actually happens?

2) I am not happy with the reactions on the springs. for example in the picture attached you can see a point load of -379.52 and the springs reactions both around 70kN.

Part of the load is taken by elastic soil you defined in the panel thickness.

[Anonymous]

1) when I run the calculation, but not every time, usually the third time I run the calculation without save it, close it and open it again. If I open it and run the calculation the first time this does not happen.

2) do you mean the load is take by the springs or is there something else I ignore?

[Artur.Kosakowski]

1). I'm not able to reproduce such situation. Please try to install SP 5 for Robot 2014 and check if youi have the same issue.

2). You defined a spring in the supported node and springs under each of surface element of the panel. They work together therefore part of the 300 kN force you applied goes to the support (70 kN) whereas the rest to the elastic soil under the slab. In most situations such "doubled" definition of boundary conditions is done by mistake but this is for you to verify 

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[Anonymous]

Can you please show me how to delete the springs under each surface of the panel?

[Artur.Kosakowski]

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[Anonymous]

Hi,

I am checking the provided reinforcement of the RC slab. Is possible to avoid the peak of reinforcement required on top of the columns? It is a small portion of slab (just above columns) but requires a lot of reinforcements and  if I don't add these, the verification failed.

Thank you

[Artur.Kosakowski]

Please look at:

http://forums.autodesk.com/t5/robot-structural-analysis/reduction-of-value-near-supporte/m-p/4699379...

http://forums.autodesk.com/t5/robot-structural-analysis/global-smoothing-and-reduce-forces-above-sup...

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[Anonymous]

Thank you.

That work absolute fine for columns. But I was not able to do the same with a core in the middle of my slab. I have defined the linear support like a wall of thickness 450,  but in the corners of the core the moment  is huge and if I use the reduction near support the value does not change.

I have tried also to increase the thickness of the wall to 800 but nothing.

I have attached the model if you want to check it:

http://www.filemail.com/d/jyrysluzvzsdnsu

Thank you again.

[Artur.Kosakowski]

Try to replace linear support with nodal supports of defined column size 450x450. Let me know if this works for you. Thank you.

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[Anonymous]

Thank you it works now. Good idea!

Now I have a problem with the provided reinforcements:

Like you can see:

-error 1: I have defined a bigger area, but it says there is a point with 0 reinforcements.

-errors 2&3: I have draw a big area with 16 at 200=1005mm2 and a small area with 12at200=565mm2 (565+1005= using 20 at 200). I want to use 20 at 200 only in this small area. the window on the right makes the sum of the 2 areas and it is in green (so it should be fine). but I have these 2 errors. if I put 20at200 in the small + 16at200 in the big I don't have these errors anymore. so I don't understand if it makes the sum or not.

thank you

[Artur.Kosakowski]

Could you attach the file with generated provided reinforcement?

[Anonymous]

http://www.filemail.com/d/vwrkddmztknoqfd

Thank you

[Anonymous]

Hi Artur,
did you have any chances to check the model?

[Artur.Kosakowski]

The warning are excessive and caused by incorrect check of the distances to the neighbouring bars checked for finally generated rebars (slab provided reinforcement layout). If you made the definitions of zones like on the attached picture you will reduce it to a single location at the very edge of the slab which is really the one to ignore.

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[Anonymous]

Sorry but from the attached picture I can't understand how to define the zones and if I have even 1 warning I can't run the calculation for the provided reinforcements.

[Anonymous]

Is it possible to generate reinforcement drawing for each direction? (top X, top Y, bottom X and bottom Y)
thank you