Storage Tank Pontoon Volume

[mecheng1818]

all,

i am trying to calculate the volume of a pontoon on a single deck floating roof tank. eventually i will use this in the upthrust calculation.

is there any set formula to use or an excel spreadsheet?

Thanks.

 

[chicopee]

Shouldn't it be =(the weight of the roof + frictional force along the wall of the tank + wind loading on the roof+ weight of pontoon ) divided by the product density?
That volume will be minimum, another word, almost totally immersed but floating pontoon because of the moment effect of the wind uplift on half the roof and wind downforce on the other half of the roof; I am assuming roof is shedding rain water.

 

[mecheng1818]

actually all i need to do is calculate the volume of air displaced by the pontoons (that is, volume of the pontoons) VS the weight of the roof.

simple calculation, its just the pontoon volume calculation due to its circular and trapezoidal shape that is giving me a little trouble.

engineering noob here

 

[jmiles]

Not to be overly symplistic, but i always break those shapes up into simpler shapes. i havent seen your exact geometry, but why not extend the lines of the trapezoid to make it a cone, then calculate the volume of the two cones, the one large, and the second part that does not actually exist, subtract and voila.

 

[rb1957]

how big are these pontoons ? can you put them in a bathtub ?

else as jmiles posts, divide the shape into simple volumes (tetrahedrons, prizms, ...)

 

[mecheng1818]

i will start breaking them up into smaller shapes/slices.

on to the calculation of upthrust vs weight of the roof.

 

[chicopee]

Mecheng1818, I think that you should have brought those two additional facts in your original post before I gave you an answer.