Buoy uplift calculation

[Ywiebyee]

Hello all,

This is my first post !
I am facing a forces/uplift calculation issue and I am seeks for advice.
I would like to calculate the required buoy uplift to lift a section of 40 m of pipe from the seabed. I attached a drawing for clarity. The values are not exact, I am looking for a general formula / approach to calculate uplift for different pipe properties and tie in heights. My first impression was that the buoy uplift is equal to the total weight of the lifted pipe, but it seems that this is incorrect. Can you please help ?
Many thanks.

 

[IRstuff]

Your drawing shows the pipe bending, which requires additional force. Additionally, if the pipe is laid into mud, there will be suction force from the mud.

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[zeusfaber]

Have a look at the Wikipedia article on "Catenary" for a starting point.

A.

 

[EdStainless]

Are you going to excavate so that there is no overburden?
If so then it is a simple statics problem.
If the pipe is not free and clear of the seafloor then the forces can be very much higher.

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P.E. Metallurgy, Plymouth Tube

 

[6667894]

Please find the attached photo, am sure it will help....