The Analysis Methods Of Warships Structure Strength And The Software System Development

For a long time,the structural design and strength check of ship has been executed on the basis of military standards which promulgated by government.The longitudinal strength calculation of conventional ship that ranges in normal scale is performed in approximate calculation method,and the process is mature enough;while at the case of structural damage,the floating state of the ship changes,external load redistributes,and the structural integrity is destroied.It’s neccessary to re-evaluate its residual strength to ensure the safety of structure.The table method is generally the traditional method,which needs a large amount of work and a complicated process.In order to analyse the longitudinal strength and residual strength after damage more efficiently and accurately,the Visual Basic6.0 language was taken to the secondary development of three dimensional design software-Solidworks,and the ship structure strength analysis software system was developed.This system mainly includes the following two main modules:the longitudinal strength and residual strength analysis modules which this paper introduces them in details. The longitudinal strength analysis module includes external load calculation, hydrostatic shear bending moment calculation, wave bending moment calculation, slamming vibration bending moment calculation, section modulus calculation, the longitudinal bending stress calculation and military specifications intensity check and the total longitudinal strength of ships is calculated, and then outputs the total longitudinal strength calculation. Residual strength analysis module includes the float state of structure calculation, hydrostatic curves calculation, the external load calculation, hydrostatic shear bending moment calculation, wave bending moment calculation, section modulus calculation, the residual bending stress calculation and the residual strength calculation under the standard of Lloyd’s army, residual strength of damaged ship is calculated and checked, then outputs residual strength calculation. In addition, the help module of this systemincludes chinese ship desigh rules, Britain Lloyd’s military vessels design rules and User guide for query and reference.The main innovation of this thesis:1. General Longitudinal bending strength analysis for a complete ship is based on a three-dimensional model, the more accurate and faster than manual form, of course, the traditional calculation method to calculate is provided;2. the residual strength analysis for the ship after damage is also based on a three-dimensional model, and using military standard criteria Lloyd’s calculations, this method also provides spreadsheet calculations, the domestic research in this area is not very common.The software system compiled in this paper was based on VB programming language, Developed for ship structural strength analysis in engineering application software system with Solidworks.The interface of the system is simple, convenient and easy to use.lt can save lots of manpower and material resources by Using this system for the longitudinal strength and residual strength calculation, this system improves the calculation precision and efficiency of design significantly which gets a certain practical value.