The Research Of Simplified Model Evaluation Based In The Main Damaged Ship Hull Residual Strength's Appraisal Method

Research of damaged warship's residual strength is one of the main aspect of its life's calculation. In the passed,many people in this area have do many words about it. But the workload of evaluation based in the main damaged ship hull is so much that trying to find a formula is a significative work. Taking a certain warship as an example, this paper makes a discussion about the residual strength of the hull after its attacks by a Guided Bomb Unit and a torpedo .The research about the residual strength problem was mostly only results of calculating a particular demolition point in the past. However, based on relevant data, this paper selects more than one demolition point and makes a series of calculations.The beginning of this paper analyzes the position and size of the damaged point and then calculates the parameter of unsymmetrical section. Generally speaking ,the damaged areas of the warships are different as the arms, according to the differences of the position, they are divided into above the waterline and under the waterline. After the ship is attacked by a Guided Bomb Unit , the damaged position is above the waterline, according to giving the position of the damaged area, to find the unit, then to cope these numbers with the package which had been developed. After the ship is attacked by a torpedo, the damaged position is under the waterline, making water enter the cabin and the external loading change. This paper calculates the ship's external loading after its body damage according to Vlasov's calculation theory. At the end of the paper, we choose the fully plastic moment as the criterion of the damaged warship's residual strength and calculate the fully plastic moment of different damaged section. Based on that, we plot several curves which depict the change of the fully plastic moment on different damaged sections. We also make some sample reggssions of the trend.Because of the given numbers are limited, while the course needs many numbers, a series of imagines are made in the paper. Then use the package to regression the numbers, and get a series of pictures. The curves drew in this paper can provide facility for the analysis of the residual strength problem and will have certain value of reference for the research of the ship vitality.