The Calculation Of Shear Properties Of Thin-walled Structure Section And Stiffened Research

As the development of shipping business around world and the strategic plan of Chinese Navy,"from light blue to dark blue", there is increasingly demanding to ship speed. For commercial ship, improvement of ship speed means higher economic returns, and for the warship, higher speed means better combat and survivability. With the development of the catamaran, trimaran and some non-symmetrical high-speed ship, the shape of the hull cross section become more and more complex. For existing marine engineering computing, the general use of approximate Timoshenko methods to the hull cross-section, and generally think the projected area of the hull equal to the shear correction area in both of breadth and depth directions. However, this approach does not take into account the impact of shear lag and the result is different from actuality. This article will use the equivalent static method of moments to consider the effects of shear lag, so accurate calculation of the shear correction area.The accurate calculation for the shear correction area of the hull section is still in the blank, we need to buy related software from DNV and pay high prices. Domestic research scholars has been adequate theoretical analysis to the shear flow’s calculation of thin-walled section, this paper attempts to write related procedures using C++language. But for thin-walled structures stiffened shear research, the approach of use the concentrated area substitute for stiffened structure has theoretical defect, it ignores the effect of cross-sectional shape of the stiffened structure. As a major innovation of this paper, the authors attempt to create a new approach to calculate the shear of stiffened thin-walled structures.The main purpose of this paper has the following two:First, using a programming language to make exact numerical calculations to shear properties of hull section, and compared with the projected area in the engineering applications, and determine the relevant correction factor.Second, making the theoretical derivation and numerical calculation to the stiffened structure’s shear properties, and prepare the relevant programs.In this paper, the results found that for unstiffened hull sections, one direction of shear area correction factor decreases with the increase of the number of components in this direction. For stiffened hull cross-section, the part-convergence method has advantages and disadvantages in the calculation from the original focus area method, the results point that the stiffened effect to the calculation of shear can’t be ignored.