Tsuneo Tsuiji

Free Vibration for Twisted Thin Conical Shell Panels.

A numerical method for analyzing free vibrations of twisted thin conical shell panels is presented based on the Rayleight-Ritz procedure. To this end, exact strain-displacement relationships are derived by employing the thin shell theory and the principle of virtual work for free vibrations is formulated. Algebraic polynomials are used as assumed displacement functions in the analysis. Frequency parameters are analyzed for typical conical shell panels and effects of variation of the curvature of the shell and of pretwist on them are discussed. Resonance frequencies and modes of vibration obtained experimentally are compared with analytical ones. The agreement between them is found to be quite good.

Free vibrations of pre-twisted cantilevered trapezoidal plates.

In this paper, a method based on the Rayleigh-Ritz method is developed for calculating frequency parameters and modes of vibration of pre-twisted cantilevered trapezoidal plates. The double integrals of the strain and the inertia energies are evaluated approximately by the single integrals along the edges of elements, into which the plate is divided. The method is then applied for the typical pre-twisted cantilevered trapezoidal plates. The frequency parameters and the corresponding modes of vibration are analyzed. The results show that the pre-twist of the plate has considerable influences on the frequency parameters except for those of the first bending mode.

Deflections of thin-walled pretwisted beams.

薄肉断面を有する初期ねじれはりの変形解析に必要な微分方程式・境界条件を, 微小変形はり理論の立場から導いた. 初期ねじれはりのねじれ変形解析に必要な幾何学的量を明確にし, その近似式を提案するとともに, 長方形断面に対してその精度を確認した. 薄肉長方形断面初期ねじれはりの引張荷重によるひずみを, 理論的にまた実験的に求め, 両者を比較検討することにより, 本論文で導いた微分方程式の有用性を明らかにした.