thickness plating on convex curvature

[darlian]

http://www.pusatkelautan.its.ac.id//images/stories/LR_convex_curvature.JPG

according to the rule ( LR - Rules and regulation for the clasification of
naval ships,january 2006, Part 6, section 2 ) above "the thickness of
plating may be reduced where significant curvature exist beetwen
supporting members"..
Q: is the rule above only for Longitudinal construction?
what about Transverse construction? where no longitudinals available?
h = ....?

my English is not that good, pls explain in simple English.....
thanks in advance...

[Ilan Voyager]

Yes, the rule is only applicable on longitudinal system of construction, as in transverse construction the scantlings of the hull plates are already calculated with the transverse elements and the curvature.
Apply this rule with a lot of caution, and so not forget the the plates must be thick enough to resist to buckling and also to local loads like grounding the boat.
A max coeff of 0.7 is very low as the rigidity of a plate (its modulus) varies with the third power of the thickness.
A common "disease" of the too lightly built metal boats is to show after a short time in sea the print of the "ribs" and stringers through the hull.
What kind of boat and what material (steel or aluminium) are you designing?

[lazeyjack]

If you look at my gallery
I can not tell you how much strength is added by shape, it is simply unbelievable

[darlian]

thanks a lot for the answer, it's really a big help...
to ilan voyager, i was designing 30 m steel yacht.
to lazeyjack, your gallery really open up my mind...