An Analysis of Practical Use Experience of Ultimate Hull Girder Strength Criterion and Some Features of Hulls Ductile Collapses

Abstract

Follow-up to the survey report [1], containing in-depth study of this problem, basically, since 1965, in the present report the almost 100-year’s experience of usage of the ultimate plastic strength criterion (U.S.C) in the Russian and Ukrainian practice of design of hulls of ship of different destination is reviewed. On the basis of comparison of results of computational and experimental estimations of an ultimate bending moments (Mult) and characteristics of their variability the expediency of usage of the (Mult) lower boundary by Boobnov-Papkovich-Shimansky method with a more precise estimation of carrying capacity of longitudinals by the generalized method of C. Smith is substantiated. These recommendations may be used also for estimation of the hull ultimate strength of FPSO (Floating Production Storage and Off-loading Units), the structure of which is similar to the hulls of modern tankers with the double bottom and double sides.