Research On Structural Sate Assessment And Navigation Safety Decision Of Ultra Large Ships Based On Monitoring Data

The structural safety of ultra-large ships is receiving more and more attention.Structural safety is the basis for the normal operation of ultra-large ships.However,a series of strength problems are caused by hydroelastic effects such as slamming,wave induced vibration and torsion.If these strength problems are not taken seriously,it will seriously affect the navigation safety of the ship.By installing a sensing system on the structure of a very large ship,a hull structure safety monitoring and evaluation system is established to provide early warning and auxiliary decision-making recommendations for the safety of the large ship structure,to avoid the dangerous state of the hull structure,and to enhance its ability to resist risks It has important practical significance.In view of the above background,the research contents of this paper mainly include the following aspects:1.Research on the safety monitoring and evaluation index system for ultra-large ships.Based on the design technical indicators of ultra-large ships and the operating characteristics of real ships,an evaluation system for the equivalent impact of torsion and slamming flutter on the hull structure safety is established,and designed the system to the evaluation system;2.The method of processing and analyzing the monitoring data was studied.The method of analyzing and analyzing the statistical value of monitoring data,the method of analyzing and analyzing the short-term probability distribution of amplitude,and the method of analyzing and analyzing high-and low-frequency response data are studied;3.The monitoring component algorithm based on structure monitoring data is studied.According to the safety index system,the algorithm based on the hull structure state data(physical quantity obtained from the monitoring)corresponding to the monitoring component is researched,mainly the inversion calculation of warping stress and slamming pressure;4.Research on decision-making database for navigation safety based on online assessment results.A numerical analysis method is used to establish an expert system for the structural response status of ultra-large ships under different loadings,different speeds,different wave directions,and different sea conditions.Based on the results of the system and structure prediction,reasonable navigational aid decision-making opinions are automatically given.