Stress and strain assessment of ship structural elements in ultimate longitudinal bending state

In operation mode, ship hull may encounter dangerous situations, especially in cases of hogging or sagging conditions. These are two cases where the bending moments acting on the hull are the largest, causing the hull to reach the ultimate state of longitudinal bending. At this state, the longitudinal structural elements in the midship will appear as tensile or compressive stress due to the corresponding tensile or compressive strains. These stresses will be different and can reach the material's yield stress or the structure's ultimate stress. Therefore, this paper will study the stress-strain relationships of the structural elements on the midship of four bulk carriers. The current study specifically focuses on analyzing the stress and strain of the structural elements in top-side tank area of selected bulk carriers. The incremental iterative analysis method is applied to create the stress-strain curve of each group of structural elements. The summary, analysis, and evaluation of the results on stress and strain will be presented in this paper.