The textbook is devoted to the problem of ensuring the operational strength of ships. It proposes approaches to assessing the strength of hull structures with operational defects, as well as schemes for reinforcement and modernization of structures. The development of the theoretical principles of ship structural mechanics in operational strength problems is carried out on the basis of the achievements of modern computer mathematics and high-performance information processing tools. Analysis and forecasting of current situations in assessing operational strength in complex dynamic environments is based on the integration of ship structural mechanics methods, dynamic catastrophe theory and modern intelligent technologies.