The Smith method has been improved to calculate the ultimate strength of the semi-submersible platform during splitting and closing when considering the overall instability of the brace, in order to study the influence of the fatigue and corrosion on the reliability of the structural ultimate strength of the semi-submersible platform. A random time-varying model of the structural ultimate strength of the platform considering the effects of fatigue and corrosion is established based on the random process theory. The time-varying models of wave loads and hydrostatic loads are established for a semi-submersible platform. The time-varying reliability of the platform structure is calculated by using the parallel system method, and is compared with the annual instantaneous reliability.

Supportability analysis is a series of analysis activities to assess the equipment supportability, influencethe supportability design, and to obtain the information and data of the integrated logistics support during the life-cycle of the equipment. The supportability analysis of the ship equipment is a complex system engineering which is implemented by the cooperation of general, system and equipment.It can not only develop the inherent supportability of the ship equipment, but also provide comprehensive and accurate data sources for the planning of supportability and the establishment of informative support methods. The supportability analysis technology of the ship equipment is studied for the typical application scenario to generate data packets of the ship integrated logistics support. The method and process of the supportability analysis are identified to provide support for the implementation of the ship integrated logistics support.

The characteristics of ship equipment include not only the functional performance, but also the common quality characteristics including the reliability, maintainability, testability, supportability, safety and environmental adaptability. Functional performance that focuses on the ship function has attracted sufficient attention in the product design. However, the common quality characteristics become more and more prominent due to the more complex system with the innovative development of new ships and the application of high technology. During the ship life cycle, the design and analysis of common quality characteristics that focus on system faults become the main factor that imposes limitation on the development of ship equipment. The design and analysis of the common quality characteristics of ships are then carried out based on the characteristics of ship equipment.