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stroxy
Posts: 191
Registered: ‎12-06-2011

RC Column design

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09-16-2012 01:14 AM

I notice  very high internal moments/eccentricities being reported in the calculation note for a RC column designed with seismic disposition (DCM) according to EC8.  I have tried to figure out the cause, but after searching through various results tables such as internal forces, nodal displacements, applied loads, I am still at a loss. I have attached screen shots of the calculation note plus tables mentioned . Would appreciate some info on where these high moments/eccentricities are coming from or where RSA gets these values.

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pp2008
Posts: 529
Registered: ‎06-23-2008

Re: RC Column design

09-17-2012 02:13 AM in reply to: stroxy

It seems that it is some port of the effects you observed for the model mentioned in this post:

http://forums.autodesk.com/t5/Autodesk-Robot-Structural/column-basement-wall-interface-singularity-i...

 

I will return to you as soon as some conclusions are known.

 

BTW: are you observing it for EC8 seismic dispositions in the final edition of EC1 (EN 1991-1-1:...) or in the EC1 pre-norm (ENV 1991-1-1:...)?

It is strongly recommended to use the final edition.

 

Regards,



Pawel Pulak
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Mentor
stroxy
Posts: 191
Registered: ‎12-06-2011

Re: RC Column design

09-17-2012 02:26 AM in reply to: pp2008

Thanks Pawel

 

yes it is from the same model. 

 

BTW: are you observing it for EC8 seismic dispositions in the final edition of EC1 (EN 1991-1-1:...) or in the EC1 pre-norm (ENV 1991-1-1:...)?

 

Did you mean final edition of EC2?

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pp2008
Posts: 529
Registered: ‎06-23-2008

Re: RC Column design

09-17-2012 03:32 AM in reply to: stroxy

Did you mean final edition of EC2?

 

Yes.

 

Regards,



Pawel Pulak
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Mentor
stroxy
Posts: 191
Registered: ‎12-06-2011

Re: RC Column design

09-18-2012 01:42 AM in reply to: pp2008

Hello Pawel

 

Am i correct in assuming that the internal forces shown in the ULS verification of the Column calculation note in the RC Column design module are imported directly from the analysis module and that I should be able to locate these values in the internal forces tables of the analysis module?

 

 

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Product Support
pp2008
Posts: 529
Registered: ‎06-23-2008

Re: RC Column design

09-18-2012 02:53 AM in reply to: stroxy

Yes, it you open the table of forces the values at the tops of the columns should correspond to the values in Loads table in RC Column design.

 

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Regards,



Pawel Pulak
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Mentor
stroxy
Posts: 191
Registered: ‎12-06-2011

Re: RC Column design

09-18-2012 04:36 AM in reply to: pp2008

Then there must be a bug somewhere, because looking at the design value of Msdz 858.36KNm used in the ULS verification and the global extreme value of 5.15KNm from the internal forces table, something does not look right.  

 

Any news from the development team yet?

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Mentor
stroxy
Posts: 191
Registered: ‎12-06-2011

Re: RC Column design

09-18-2012 05:05 AM in reply to: stroxy

sorry forgot to attach screenshots

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