Reseach on Strength of Ships and Offshore Structures Sbujected to Hydrostatic Pressure.

点击翻译按钮获取中文摘要

In order to obtain critical pressure to cause general instability of reinforced cylindrical shells, the buckling equations were derived based on the energy method. The buckling pressure is calculated and compared with the experimental ones indicating good accuracy of analytical model. Recent advances of numerically controlled machining ennable us to estimate buckling pressure of sttifend sylindrical shells accurately by experiments. Machined models can regarded as perfectly cylindrical shells, and the validity of modelling for numerical method will be abl to confirmed by comparing theoretical results with experiment. in order to analyse the ultimate strength of ship and offshore structures, idealized "plate element" and "stiffend element" in the framework of the idealized structural unit method (ISUM) were deceloped. A simple calculation method is developed to simulate the progressive collapse behavior of a cross section of a ship's hull under longitudinal bending moment. The dynamic pulse lateral bucling of a T-shaped section thin walled beam and the effectiveness of asymetric section steffners in large deflection due to static loads were studied by expriments with simplified calculations. A system is developed for probabilistic strength assessment of semi-submersibles under the extreme sea. Through numerical examples for a typical platform, the properties of critical section or dominant failure modes and their probabilities of occurrence are investigated. Crush analysis codes of structural members have been developed by using low-order finite elements, which have been applied to The analysis of the crushing behaviors of steel tubes as well as the collapsing behaviors of ring-stiffened circular cylinders subjected to external pressure. the validities of the developed codeshave been demonstrated through the comparisons of numerical results with the experimental observations.