Above Ground Flowlines

[Johnrem]

Dear Specialists:
Is there any body in this forum who has experience with Above Ground pipelines (continuously in contact with soil) modeling using Caesae software?

Thanks

 

[Johnrem]

Good Morning every one;

Could someone indicate me where can I find specialists of stress analysis using Caesar ?

 

[LSThill]

http://www.aptecheng.com/experience/pdf/Thill_Leonard.pdf

 

[Johnrem]

Thanks Leonard;

I need your advice concerning modeling of above ground pipeline.

What is the best way to model above ground pipelines continuously in contact with soil? Is it by providing supports with short span or by using Buried modeler included in Caesar II.

In case we use Buried Modeler of Caesar II, what will be the Burial depth since the pipe is burried infact?

 

[C2it]

You should check out the Caesar II forum at

http://www.Coade.com.

There is a good search facility and this question has been raised a number of times.

 

[Johnrem]

The question was raised by me on that forum, but no answer

Thank u

 

[DSB123]

Johnrem,
I thought LSThill would have responded by now as you asked him for more information and he could back up him extensive experience by helping you out.

 

[Johnrem]

No body answered me until now...

 

[DSB123]

Johnrem,
Thought as much. So the CV posted was not much help then? You never actually get help from the poster - normally just a list of papers to refer to or a plug for FEpipe etc.

What I would do is model the system as a buried line with the lateral stiffness input as being equivalent to the friction between the pipe and the ground.You will have to come up with a figure dependant upon the "soil" the line is sitting on. The vertical stiffnesses - I would use a very stiff value for the downward values and as low as you can get away with for the upward resistance to movement. The axial resistance to movement - I would use the same as the lateral stiffness you come up with. The problem you have got is that if the stiffnesses used generates high compressive loads then the lateral restraint due to just the friction will not be enough to prevent lateral "buckling" of the line to the same extent as normally higher values used in buried lines. And the problem is you do not know where the pipe will move laterally in practice as slight imperfections in the straight routing of the line will become significant.

Sorry I can't help in any more detail but that's the way I would start to consider the problem.