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Member
an.pisey
Posts: 3
Registered: ‎04-08-2012

Pile cap model in robot

498 Views, 4 Replies
04-08-2012 10:05 PM

Dear all members,

 

Please kindly give me a concept modelling for Pile cap desiging in autodesk robot. I used to model as a slab whose thinkness is equal to the real pile cap. The piles are modelled as column under slab and column above pile cap are model as a column. Finally the result of pinching shear is not satified and rc bar is also so high comparing to manual caculation

 

Thank you so much,

 

Pisey

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Valued Mentor
AJA14
Posts: 490
Registered: ‎11-01-2011

Re: Pile cap model in robot

04-09-2012 04:19 AM in reply to: an.pisey

Hi, I'm not sure how the Robot People would do it so it would be good to know. What we usually do is model the piles as elastic supports and use rigid links to model the full pile behaviour (by adding nodes on the pile periphery and providing rigid links with the center of the pile). As for the column, we use a distributed load instead of a nodal force. Give it a try.

When it comes to modeling anything, there are so many ways, but I think the Robot guys probably know the best way to receive accurate results.

Ali Al-Hammoud
Structural Design Engineer
MZ & Partners Engineering Consultancy
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Valued Mentor
tony.ridley
Posts: 652
Registered: ‎09-07-2011

Re: Pile cap model in robot

04-09-2012 05:27 AM in reply to: AJA14

You could use the plane stress option but this won't check for required reo or for punching shear automatically.  

However it will give you the stresses that you need to provide reo for.

 

I think if you model it as a slab element it won't be accurate as Robot will assume the slab/shell is a flexural member.  

I think you normally use a strut/tie method for pile caps which will result in different amounts of reinforcement than you'd get from flexural design analogy.  

 

Tony

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Distinguished Contributor
gustavo.c.vasconcellos
Posts: 107
Registered: ‎04-15-2011

Re: Pile cap model in robot

04-09-2012 10:52 AM in reply to: an.pisey
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Member
an.pisey
Posts: 3
Registered: ‎04-08-2012

Re: Pile cap model in robot

04-10-2012 06:29 PM in reply to: tony.ridley

Dear Tony,

 

yes, I think you have reason. anyway, do you think Robot can design element in Struct and Tied analysis methode or not? could you give me some idea, if i want to calculate Pile Cap by Robot as i want to check punching shear also.

 

Thanks,

 

Pisey

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