Research On Security Of Residual Strength Of Damaged Ships

With the process of globalization, the shipping industry is growing at a high speed, playing a more and more important role in the international trade. However, along with the development of large sized and higher speed vessels, collision and grounding accidents happen inevitablely, resulting in structure damage, oil leakage and casualties. Therefore, the study of structure safety of damaged vessels is of vital importance for safety protection, economic development and environmental conservation.Once collision and grounding accident happen, on one hand, the floating status and loading would change significantly because of inlet water. On the other hand, Structural damage directly weakened the hull structure bearing capacity and the hull strength decreased. At the same time, shear force and bending moment changed, due to the lack of strength and fracture. In order to avoid civilian casualties and the pollution to the environment caused by the damage of the ship, we need to assess the safety of damaged ships so as to make towing measures and rescue plan.This paper mainly studies the load and residual strength of damaged ships. First of all, it based on the theory of insubmersibility to determine the floating state and external load. Then, based on the rules and regulations for the construction and classification of sea-going ships, by using finite element software to establish three-cabin model of bulk carriers and chosing reasonable external load and boundary conditions, it find the stress law and weak links of the broken component, in order to provides a reference to improve the strength of damaged ships. Secondly, it use the arc-length method to solve the ultimate moment of simplified model of the bulk carrier, as a reference of the ultimate bearing capacity. Finally, it describes the residual strength evaluation method based on the section modulus and ultimate moment, and analyze the residual strength based on the section modulus of the bulk carrier. By the results of the above analysis, we hope it can play apart in promoting the analysis of the safety performance of damaged ships.