Hor. & Ver Accelerations
Hor. & Ver Accelerations
(OP)
I am designing a flare boom for an offshore platform. I have the following information provided to me regarding the platform:
Phase Pitch/Trim Angle Horiz Accel. Vertical Accel.
(Deg) (m/s^2) (m/s^2)
Tow 20.0 9.6 15.1
At Site 0.17 0.69 9.9
Notes:
1) Horizontal accelerations include gravitational effets due to pitch/trim angles.
2) Vertical Acceleration includes gravity.
My question is whether I can simulate the effects of motion by applying an equivalent G-Force in the horizontal and Vertical directions. For example for the "Tow" Condition, can I use 9.6/9.8 = 0.98g for Horizontal and 15.1/9.8 = 1.54g for vertical? I realize that these loads have to be combined with the other applicable loads per API RP 2A.
Also, how would the Pitch/Trim angle be considered given that the Horizontal accelerations indicate that Pitch/Trim angles have already been included (Ref. Note 1)?
Thanks,
Meca
Phase Pitch/Trim Angle Horiz Accel. Vertical Accel.
(Deg) (m/s^2) (m/s^2)
Tow 20.0 9.6 15.1
At Site 0.17 0.69 9.9
Notes:
1) Horizontal accelerations include gravitational effets due to pitch/trim angles.
2) Vertical Acceleration includes gravity.
My question is whether I can simulate the effects of motion by applying an equivalent G-Force in the horizontal and Vertical directions. For example for the "Tow" Condition, can I use 9.6/9.8 = 0.98g for Horizontal and 15.1/9.8 = 1.54g for vertical? I realize that these loads have to be combined with the other applicable loads per API RP 2A.
Also, how would the Pitch/Trim angle be considered given that the Horizontal accelerations indicate that Pitch/Trim angles have already been included (Ref. Note 1)?
Thanks,
Meca





RE: Hor. & Ver Accelerations
Yes, I think what you are proposing is correct.
On the pitch/trim angle question I think what is meant is that when the load is rotated, in addition to the inertial components of the load there are static vertical and horizontal components of the load (- because the load is inclined instantaneously) and that these effects have already been included in as equivalent accelerations. So you don't need to add anything else, just factor the loads as you propose. This way of specifying tow loads etc is pretty common in the offshore industry.
I hope this is helpful.
Good luck.
RE: Hor. & Ver Accelerations