Pipeline Stacking Calculation

[atedionyahoo]

Re concrete coated Pipeline Stacking calculation:

Question A) To calculate concrete crushing effect between pipelines, how much is the effective contact length? (I am heard due to concrete nature, the whole length of concrete does not contact with its counterpart concrete) (I use Roark formulation for contact effect of cylinder on cylinder)

Question B) To calculate stress in steel pipe (coated with concrete), How should the stress distribution in steel pipeline be calculated? (I understand API RP 5LW is not used for stress in steel pipe coated with concrete)

 

[BigInch]

Pipes are not usually stacked in contact with each other. They will be placed on a truck with saddled spacers. Therefore a pipe will only make bearing contact against the width of the spacing elements.

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"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[atedionyahoo]

thanks, however kindly note that stacking is relevant to concrete coated pipeline carriage by cargo barge or stacking on the laying barge. in this case i understand wood bearing strip is used to avoid direct contact between pipe and deck.

however, in pipe stacking calculation the following cases should be checked:

case 1) contact between concrete and concrete (worst case the bottom pipe row and the penultimate row)

case 2) contact between concrete pipe and deck (without wood timber) (worst case between bottom row and the wood) (this is just for information because in reality this leads to undesirable results and as such it is concluded that below case 3 to be used)

case 3) contact between concrete pipe and wood bearing strip on deck (worst case between bottom row and the wood)

case 4) steel pipe capacity against the loads

case 5) deck capacity (force per unit area) to carry load

my question is relevant to effective contact length for above cases 1 & 2 (for case 3 the effective length is bearing length of wood strip)

(i have used DAF to consider the effect of pipe dynamic movement as well)