FEA Of Structural Strength For Bulk Carrier Cargo Holds Based On ABAQUS

The Computer Aided Engineering technology (CAE), which is based on the finite element theory, has been widely applied to the simulation and design of ship structures. Accompanying with the development of CAE technology, ship structure engineers can consider the effects of various types of loads on the simulation of ship structures more comprehensively. On the strength analysis of ship structures, the early methods were based on the classical thin-walled beam theory; it is dominated today however by finite element simulations of cargo holds or whole ships. Limited by the abilities of computer hardware and software, it is difficult to conduct a finite element simulation of a whole ship, current ship structure simulations are accomplished mainly on the representative cargo holds.According to the "Common Structural Rules for Bulk Carriers" set by the International Association of Classification Societies (IACS) a finite element model of a dry bulk cargo hold was established with the general-purpose CAE software ABAQUS in the thesis, with the properties of large open-type dry bulk cargo transport ship considered. The range used to the model covers 1/2+1+1/2 holds, with 88 plat floors. In the finite element model some unimportant structures of the related ship components are simplified, e.g. the lightening holes on the plat floors are ignored.According to the specification, the loads and boundary conditions corresponding to four working conditions H1 (head sea, sagging), F1 (following see, sagging), R1 (maximum roll) and P1 (maximum external pressure) are set on the FE-model under the full-loading condition. The loads applied on the model include:the hull girder load, hydrostatic pressure, hydrodynamic pressure, and cargo pressure as well as the ship weight. The displacement, strain and stress fields of the cargo hold are numerically simulated by using ABAQUS.From the numerical results the following conclusions can be drawn:(1) the larger stresses mainly arise on the shipboard at the midship section, the main deck and the hatch coaming; (2) for all four load cases stress concentration occurs at the corners of the hatch near the midship section; (3) on the inner and outer hulls, the larger stresses arise near the main deck and the ship bottom; (4) under the four load cases, large deformation can be found on the hatch coaming near the midship section; (5) for load case H1, the head sea compartments deform more than the midship compartments deform, stress concentration and larger deformations can be seen on the upper part of the head sea section; (6) for load cases R1 and P1 (horizontal wave conditions) and with the port side being the weather side, larger deformations occur on the part of the starboard side near the midship section.