The Study On Comparison Of Direct Strength Calculation Methods For Floating Dock Structure

In the calculation of structural strength applying of finite element method, the linear load function which is distributed along a straight line can be exerted on the basis of the theory of equivalent nodal load, also can be loaded simply by means of discrete load function. For the structure calculation model which is in force balance state, the constraint of three nodes hinged can be used to restrain translation and rotation of the model, the Inertia Relief can be used as well.In the process of the structure strength of a floating dock whose lifting capacity (L.C.) is equal to a 3500 DWT ship being assessed, the comparison was made between the analysis results of these two different models. The effects of the loading mode and the constraint condition on the analysis results were demonstrated. Simultaneously, the appraisal of the advantages and disadvantages of each loading way and constraint condition was discussed. The application suggestions were given as well.The present paper is divided into three parts.1) The finite element analysis model of full dock was built using the software of MSC.Patran&nustran. According to the CCS rules, the strength of full dock was assessed. And the main results of the stress had been analyzed.2) In the analysis model of the present paper, the lifting load and the constraint conditions in the analysis model of applied CCS rules were changed into the quality element and the inertia relief. And the stress results of the corresponding models were gained through the calculation.3) The comparison was made between the analysis results of these two present models and results of the model using CCS rules. Then the scope of application of each loading way was discussed. The suggestions of application of different constraints were given as well.