Bending Analysis of Plates with Oblique Stiffeners

摘要

The most of ship structures are composed of stiffened plates. However analytical method of plates structure with obliqe stiffeners and non-rectangular plates subjected to bending load are not enough to be completed in practical sense. This paper presents an analytical method on strength of non-rectangular plates and plates with oblique stiffeners by improved finite strip method proposed by authors to lighten the volume of calculation and to obtain accurate solution. Displacement functions of strip elements are employed the approximate functions obtained by Kantorovich's method. Those give exact solutions of the equilibrium equation of plate bending in simply supported condition and very close ones to them for other cases. And this dealing is effective to make decrease of discretization errors. The problems on geometric extension contained in non-rectangular plates and oblique stiffeners are settled by using the method oflinear transformations of variables and by applying Fourier's approximation. This procedure is able to integrate analytically at the calculation of stiffness matrix and load matrix and on the contrary it is necessary to integrate numerically in the case of using of the shape functions in establishment of coordinates transformations. To investigate accuracy and convergence of solution, we analize a square plate subjected to bending load by using non-rectangular elements and this results prove that comparatively accurate solution is able to be obtained by this method in spite of a few degree of freedom. The effectiveness of the shape of element is demonstrated to analize a bending plate in rhomboidal shape and plate structure with oblique stiffeners. The effects of oblique stiffeners for plate according to varying slant angle are clarified.