Ultimate Limit State Assessment of Stiffened Panel Structures for Very Large Ore Carrier via Nonlinear Finite Element Method

Reduces weight of hull structures designed for a very large carrier plays an important role as the economic efficiency is the most significant aspect. It is known that the traditional allowable working stress approaches with high safety and reliability, it means that the hull structural weight is higher than the actual requirement in operation. Recently, the limit state approach has been widely applied for analysis and assessment of marine structures, the limit strength of structures is determined by nonlinear finite element analysis (FEA) method. A Very Large Ore Carrier (VLOC) is designed by using IACS Common Structural Rules (CSR) method in this article, and pre-CSR method is adopted to improve cross-sectional of the bottom and deck structures. Given that the stiffened panel under the combination of axial or biaxial compression and lateral pressure loads for computation, ultimate strength of the ship structures designed by using the aforementioned method are analyzed by using the nonlinear finite element method (FEM). The results show that the difference of ultimate strength of ship structures designed by using pre-CSR method and CSR method is able to neglect. It can be seen that the weight of hull structure can be reduced by 0.56 percent (640 tons in this case) without reducing ultimate strength when pre-CSR method is applied.