Radoslav PAVAZZA, University of Split, FESB, Ruñera Boškovića 32, 21000 Split, Croatia Bože PLAZIBAT, University of Split, Department of Professional Studies, Livanjska 5, 21000 Split, Croatia Marko VUKASOVIĆ, University of Split, FESB, Ruñera Boškovića 32, 21000 Split, Croatia ON THE DISPLACEMENTS OF CONTAINER SHIP HULL GIRDER UNDER TORSION Summary An analytical approach to torsion of thin-walled beams of open section with one plane of symmetry is considered. The theory of torsion of thin-walled beams of open section with influence of shear, based on the classical Vlasov’s theory of thin-walled beams of open section, as well as the Umansky’s theory for closed-open sections, is applied. The general transverse loads act in the beam walls, reduced to the moments of torsion with respect to the principal pole (torsion/shear centre) only. The beam will be subjected to torsion with influence of shear with respect to the principal pole and in addition to bending due to shear in the horizontal plane trough the principal pole. The obtained analytical expressions for displacements are applied in the analysis of displacements of the modern container ship hull girder subjected to torsion, as well as in the parametric analysis of simple U sections. Comparisons with the finite element method by applying shell elements are provided. Key words: Theory of thin-walled beams; Torsion; Influence of shear; Open sections and closed-open sections; Analytics; FEM O pomacima trupa kontejnerskih brodova opterećenih na uvijanje Sažetak Razmatran je analitički pristup uvijanju štapova otvorenog i otvoreno-zatvorenog tankostjenog presjeka s jednom ravninom simetrije. Primjenjena je teorija uvijanja štapova otvorenog tankostjenog presjeka s utjecajem smicanja, na temeljima klasične teorije Vlasova za štapove otvorenog tankostjenog presjeka, te Umanskog za štapove zatvoreno-otvorenog presjeka. Opće poprečno opterećenje djeluje u stijenama štapa, reducirano na momente uvijanja u odnosu na glavni pol (središte uvijanja/središte smicanja). Štap će biti opterećen na uvijanje s utjecajem smicanja u odnosu na glavni pol, te dodatno na savijanje zbog smicanja u horizontalnoj ravnini kroz glavni pol. Dobiveni analitički izrazi upotrebljeni su u analizi pomaka trupa modernog kontejnerskog broda opterećenog na uvijanje, kao i u parametarskoj analizi jednostavnih U profila. Dana je usporedba s metodom konačnih elemenata, s ljuskastim elementima. Ključne riječi: Teorija tankostjenih štapova; uvijanje; utjecaj smicanja; otvoreni i zatvoreno- otvoreni presjeci; analitika; MKE