In the presented paper, the governing equations of a vibratory beam with moderately large deflection are derived using the first order shear deformation theory. The beam is homogenous, isotropic and it is subjected to the dynamic transverse and axial loads. The kinematic of the problem is according to the Von-Karman strain-displacement relations and the Hook's law is used as the constitutive equation. These equations which are a system of nonlinear partial differential equations with constant coefficients are derived by using the Hamilton’s principle. The eigenfunction expansion method and the perturbation technique are applied to obtain the response. The results are compared with the finite elements method. تفاصيل المقالة

This paper investigates the buckling of finite isotropic rectangular plates with circular cutout under uniaxial and biaxial loading. The complex potential method is used to calculate the pre-buckling stress distribution around the cutout in the plate with finite dimensions. To satisfy the in-plane boundary conditions, the generalized complex-potential functions are introduced and a new method based on the boundary integral which has been obtained from the principle of virtual work is used to apply the boundary conditions at the plate edges. The potential energy of the plate is calculated by considering the first order shear deformation theory and the Ritz method is used to calculate the buckling load. The effects of cutout size, type of loading and different boundary conditions on the buckling load are investigated. Comparing of the calculated buckling loads with the finite element results shows the accuracy of the presented method for buckling analysis of the plates. تفاصيل المقالة