The Load Forecasting And Response Of Structural Of Bulk Carriers Longitudinal Launching

Longitudinal gravity type slipway launching is at present, China’s large and medium-sized shipyard is widely adopted a way of launching. This method is suitable for the different ship type and ship launching weight, and has simple equipment, low fabrication cost and convenient maintenance. But it also has launched a process more complicated, the tail floating will produce very big pressure as shortcomings. Along with the development of the modern shipbuilding, created new ship appeared some new characteristics, new challenges, directly affect the slipway launching safety of the ship. In recent years the slipway launching ship hull, slipway structure damage accidents happen. So in ship design stage, when the longitudinal launching water at the bottom of the load forecast and structure response of ship research, to ensure the safety of ship’s longitudinal launching has important significance.This paper carried out the bulk cargo ship longitudinal launching load forecast and response of bottom structure. First of all, the research of ship longitudinal launching arrangement and force analysis of each stage in the water. Lay a solid foundation of theory basis and mechanics for the longitudinal launching load forecast and the bottom of the numerical simulation of structural response; Secondly, taking the typical bulk cargo ship longitudinal launch as an example, obtained a series of main parameters of water load forecast data launching calculation and water in the process of calculation of hull effect; Then, establelish the finite element model of the whole ship, various slippage state finite element simulation of the hull bottom structure. Analysis of bottom structure of potentially dangerous conditions that damage local tail bending and tail floating condition, hull area and dangerous conditions corresponding to the; Finally, respectively, to the bulk carrier cargo area in typical local tail bending condition and the bow region near the collision bulkhead in tail floating condition when the finite element simulation study. Get response region of ship hull bottom structure should be relative and dangerous working conditions, carries on the appraisal to the water bottom of ship structure strength.The main research works are listed as follows:(1) The study of ship longitudinal gravity launching of the sewer layout and force analysis of the various stages of launching process by. Analysis of longitudinal launching force four stage in the process and the adverse circumstances that may arise. To avoid or improve this situation to propose the corresponding measure, laid the foundation of theoretical basis for numerical simulation and mechanical response of load forecasting and bottom longitudinal launching of ship structure;(2) The whole ship launching process of launching calculation and load forecast.In a typical bulk cargo ship longitudinal launching as an example, to contain FRom a sliding to the beginning of the four stage a water floating in the water process completely. On the ship model in a typical high tide and high tide when the water of different assumptions, the ship’s overall water situation to carry on the numerical simulation. First get full floating support distance ways end distance, tail float distance, the first bracket distance power zone tail float gravity distance ways end distance and a series of launching calculation of main parameters of data. Get the load forecast waters on the hull effect. Draw the ship launching in the typical high tide and high tide when the water of different assumptions, the bottom will not disrupt the structure because the water depth is shallow and the conclusion of regional;(3) The whole ship launching process of ship hull girder structure analysis studies. The obtained FRom the beginning to the ship launching slide based entirely on the floating load forecast slippage, the establelishment of finite element model of the whole ship hull girder. It was all slippage state on the whole ship finite element model of finite element simulation on the bottom of the hull structure. It gets the local bending analysis of tail and tail floating condition for the bottom structure of potentially dangerous condition of damaged hull area and dangerous working conditions, and the corresponding;(4) Some bulk cargo ship longitudinal launching bottom structural strength assessment study. Analysis of two dangerous conditions obtained stress beam finite element model of the hull, the hull area and dangerous conditions based on the corresponding. Separately to the typical local conditions within the cargo area of tail bend and bow region near the collision bulkhead in tail floating condition when the finite element simulation study. So get response respectively different conditions typical of cargo area and bow collision bulkhead near the area of bottom structure. It carries on the appraisal to the water bottom of ship structure strength.