1. Multipurpose Polar Icebreaking Subsea Work Vessel
Niko Kantonen
Santeri Ihalainen

2. Hull structure
First round of calculations for the hull structure done in the structural design course
We have the first sketch of the main frame, plates, stiffeners and web frames defined
All the difinitions need to be updated
Checking the compatibility of structure with GA

3. Main Frame

4. Work flow
The process is started by estimating the pressures on different structural components
After that calculating the still water bending moment (SWBM) and wave induced moment, especially the cases where the moment gets the highest values (hogging and sagging)
To estimate the ships response in irregular sea, the Bonjean curves are utilized
For the wave loads the North-Atlantic wave spectrum -> ship response
After the loads are estimated the plate thicknesses can calculated according to the classification society rules

5. Work flow
After the plates the tertiary level response -> defining stiffener sizes
Moving on to secondary level response -> web frames and girders
Finally the hull girder response -> longitudinal strength
Check the critical buckling stresses and make sure those are not exceeded
Check the vibratory response

6. Problem area - Moonpool
The moonpool is located in the mid ship area
Space reserved around the pool for the hull structures
How should we take the moonpool in consideration in the calculations?

7. Schedule and work breakdown
First week updating the calculations done in the ship structural course
A more specific estimation of the loads will be carried out
Adding more attention to problem points including the moonpool and other discontinuity points of the ship
Checking the compatibility of structure with GA