This paper deals with the nonlinear free vibration of thick annular functionally graded material plates. The thickness is assumed to be constant. Material properties are assumed to be graded in the thickness direction according to a simple power law distribution in terms of the volume fractions of the constituents. The formulations are based on the first-order shear deformation plate theory and...

This paper deals with two-dimensional plane stress wrinkling model of a plastic annular plate. Based on energy method and the nonlinearity of strain-displacement law, a bifurcation function in polar coordinates is derived analytically. This technique leads to the critical conditions for the onset of the plastic wrinkling of flange during the deep drawing process. To find this solution, the Tres...

In this article, axisymmetric buckling behavior of piezoelectric fiber reinforced polymeric composite (PFRPC) annular plate subjected to electro-thermo-mechanical field is presented utilizing principle of minimum potential energy. Boron-nitride nanotubes (BNNTs) are used as fibers. Full coupling between electrical, mechanical and thermal fields are considered according to a representative volum...

In this article, the axisymmetric stability of an elastic annular plate with distributed internal heat source under uniform constant compressive radial loading at outer edge is investigated. The governing and compatibility equations are taken from modified Karman’s equations, which solved by shooting method. effect density on critical load investigated discussed in detail. Numerical results wit...

In this paper, an analytical approach for deriving the Green’s function of circular and annular plate was presented. Null-field integral equations were employed to solve the plate problems while kernel functions were expanded to degenerate kernels. The unknown boundary data of the displacement, slope, normal moment and effective shear force were expressed in terms of Fourier series. It was noti...

OBJECTIVE To determine abnormal MRI findings in adults hospitalized with acute severe axial LBP. METHOD Sixty patients with back pain were divided into 3 groups consisting of 1) 23 adults with acute axial severe LBP who could not sit up or stand up for several days, but had not experienced previous back-related diseases or trauma (group A), 2) 19 adults who had been involved in a minor traffi...