Slab reinforcemetn: strange peak values

[Anonymous]

Dear support,

I have a query regarding the slab reinforcement. In some areas the span of the slab is around 6,8m and the thickness of the slab is 225mm. The thickness is relatively small, therefore I get quite big deflection value in some areas which is around 50mm. The quantity of the reinforcement looks not so big what is correct because it has been calculated in order to satisfy the strength criteria only. To satisfy the deflection criteria I change the reinforcement option for this slab and ask Robot to update the reinforcement – ‘reinforcement correction’ in reinforcement parameters tab. The maximum deflection I choose is 35mm. After this I would expect to get the increase of reinforcement in nearby area of the slab with big deflection. But Robot gives quite strange reinforcement map with a huge reinforcement values in a lot of different points(please find the attached file). When I try to check the internal forces in these point they look very small. So I don’t understand why do I need to increase the quantity of reinforcement in these non-specific points? I can just ignore these peak values, but maybe there is a way to sort out this problem?

[Anonymous]

I faced the same problem

[Rafal.Gaweda]

File please.

[Anonymous]

Here it is.

[Anonymous]

I'm doing one more project and I've got the same problem. The reason of huge reinforcement quantity in some points is the stiffness factor. Somehow Robot gets big stiffness factor in some points. But I can't see any reasons for these values. I added one more query in the post 'stiffness factor for the slab'.         

[Rafal.Gaweda]

My results

Different settings to get similar deflection limit:

[Anonymous]

Thank you for your response.

As I understand in my particular case robot is not able to control deflection automatically. I need to do it changing the limit of the crack value? And what about the stiffness factor in my other post? Why sometimes do we get huge values for this factor?

Thank you for your help. 

[Rafal.Gaweda]

As I understand in my particular case robot is not able to control deflection automatically. I need to do it changing the limit of the crack value?

I just showed you different than standard way of getting deflection limit , sometimes this approach produces "nicer" reinforcement

And what about the stiffness factor in my other post? Why sometimes do we get huge values for this factor?

I did not look at it, yet.