Hull girder ultimate strength analysis of oil tanker

Diplomski rad obuhvaća analizu granične uzdužne čvrstoće trupa broda za prijevoz tekućeg tereta koristeći geometrijski i materijalno nelinearnu metodu konačnih elemenata (NLMKE) te inkrementalnu-iterativnu metodu propisane unutar IACS-ovih Združenih pravila za projektiranje (engl. Common Structural Rules, International Association of Classification Societies) brodske konstrukcije. Nakon teorijskog opisa propisanih metoda za analizu uzdužne granične čvrstoće i opisa izrade strukturnog modela, provedena je nelinearna analiza metodom konačnih elemenata glavnog rebra pomoću programskog paketa LS-DYNA. Osim programskog paketa LS-DYNA korišten je programski paket LUSA i MARS za provedbu iterativno-inkrementalne metode u koju su implementirane krivulje naprezanja-deformacije σ-ε. Preko krivulja naprezanja-deformacije σ-ε određuje se vrsta kolapsa pojedinog strukturnog elementa. Cilj propisanih metoda je određivanje graničnog momenta savijanja trupa broda. Uspoređeni su rezultati dobiveni korištenjem dva programska paketa (LUSA i MARS) u okviru iterativno-inkrementalne metode te rezultati dobiveni nelinearnom metodom konačnih elemenata korištenjem programa LS-DYNA. Osim cilja dobivanja graničnog momenta savijanja, analiziran je redoslijed kolapsa pojedinih strukturnih elemenata za stanje pregiba i progiba. Na kraju su komentirani mogućnost korištenja (dobre strane i ograničenja) obiju metoda proračuna graničnog momenta savijanja trupa.Graduate thesis includes hull girder ultimate longitudinal strength analysis for tankers using geometric and material non-linear method finite elements and incremental-iterative method prescribed by the International Association of Classification Socities, Common Structural Rules for ship construction. After teoretical description of prescribed methods for hull girder ultimate longitudinal strength and description for makig of structural models, it was conducted non-linear analysis of hull girder with the program LS-DYNA. Besides LS-DYNA, for incremental-iterative method were used programs LUSA and MARS2000, in which are inserted curves stress-deformation σ-ε. With curves stress-deformation σ-ε determined the type of collaps of each structural element. The target of prescribed methods are assessment ultimate hull girder bending moment. The results were obtained by using two program packages (LUSA and MARS) within the iterative-incremental method and the results obtained by the nonlinear finite element method using LS-DYNA program. In addition to the aim of obtaining the ultimate bending moment, also was analysied the order of collapse of the individual structural elements for the state of sagging and hogging. Finally, the possibility of using (the good side and the limitations) of both calculation methods of the ultimate hull girder bending moment are commented