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With the consideration of shipping efficiency and the limited conditions of the Yangtze River, flat and wide ship become the preferred type for River-Sea-Going ship. This kind of structure is adverse to the ship’s stiffness under longitudinal bending, transverse bending. And two-stage repeated loading brings to the fatigue assessment of the ship structure new uncertainties, so accurate cumulative fatigue damage is a matter of necessary. Based on the theory of three-dimensional potential flow, the hydrodynamic analysis of River-Sea-Going container ship under specific route is carried out. The hull motion and the load transfer function of each section are obtained. The finite element model is used to calculate the amplitude-frequency response Operator RAOs. The influence of special routes and speed factors are also considered. Based on the frequency domain spectral analysis method combined with the scatter diagram of E1 sea area, the characteristics of wave-induced load are analyzed under 10−7.5 probability level. The stress response spectrum and the short-term distribution of stress range are obtained by combining the structural stress response calculation with the whole ship finite element structure model. The long-term distribution of stress response spectrum and stress range is also obtained. The cumulative fatigue damage of River-Sea-Going container ship under the special route is evaluated by using the S-N curve recommended by the criterion. It can provide the basis for the fatigue assessment of the new type of River-Sea-Going container ship.

Inflated membrane structures make of high-strength fabric material that can be used as beams when inflated at high internal pressure. Due to their physical characteristics which are deployed and lightweight, they can be used as off-shore floating structures such as floating breakwaters and floating causeways. The paper is devoted to present experimental studies on the behavior of fabric inflated beams. The experimental result was compared with wrinkling theory. This experiment consisted of three parts. First, the beams were tested under bending load with different internal pressures and then the different diameters specimens were tested with identical pressure. The results showed that the deformation depended on the applied load, the internal pressure and the diameter. The amount of deformation increased sharply when the local wrinkles occurred and the load-displacement curve manifested strong nonlinearity. Then, an experiment of the parallel-connected beams was performed to obtain the parallel-connected effect of the load-deflection response of inflated beams. The results showed the deflection of the single beam was not twice of the deflection of double parallel beams. A floating causeway model experiment was also finished, the results confirmed the previous conclusions and the floating composite causeway was enough stable. These experimental results can be applied to provide theoretical guidance and scientific basis for design method of the floating composite structure.