抄録
The object of the present paper is to formulate the efficient method for nonlinear dynamic analyses of rotational shells by the combined use of the finite element method and the mode superposition method. In the Part 1 of the paper, the formulation of the nonlinear dynamic analyses is presented for the general shells of rotation. The nonlinear equations in the two tangential directions are solved with use of the finite element method and the two tangential displacements u and v are determined as the function of the assumed lateral displacement w. After those procedures, the dynamic nonlinear modal equations are derived. The effects of the geometrical imperfections are taken into consideration. In the Part 2, a shallow spherical cap having a clamped edge subjected to the lateral pressure is analysed for λ=5, 6, 7, 8 and 9 and the results are compared to be in fair agreement with those given by other authers. The shell subjected to the similtaneous dynamical action of auniform pressure and a concentrated load on the apex with various ratio is investigated and the results show the large a mount of reduction of the dynamic buckling load due to a slight concentrated load. The interaction formula for the dynamic buckling of the lateral pressure and the concentrated load is discussed.
