A. I. Zirka

Stress Concentration in an Orthotropic Plate with a Circular Hole under Dynamic Loading

The paper sets forth a photoelastic method for the determination of the dynamic stress concentration factor near a hole in an orthotropic plate. The stress distribution at the periphery of a circular hole is analyzed. The stress concentration factors for orthotropic and isotropic plates under dynamic and statical loading are compared

NEAR-BOUNDARY STRESS WAVE FIELD IN ANISOTROPIC PLATES UNDER IMPULSIVE LOAD

The stress wave field and the behavior of waves near the free boundary in an orthotropic plate and at the interface between two anisotropic media are studied. The results presented were obtained using the dynamic photoelastic method and optically sensitive fibrous models. Experimental data for impulsively loaded plates with various boundary conditions are analyzed

Stress Wave Field Near a Notched Boundary in Anisotropic Plates under Impulsive Loading

The stress distribution near a rectilinear boundary and a boundary with a notch of different depths in an anisotropic plate is analyzed. The plate boundary is under the action of a surface or embedded impulsive source. The results presented have been obtained using the dynamic photoelastic method for optically sensitive orthotropic plates. The results for orthotropic and isotropic plates with different ratios of notch depth to wavelength are analyzed

Theoretical and Experimental Investigations of the Stress Concentration in Nonthin Cylindrical Shells with Rectangular Openings

The problem on the stress state of cylindrical shells with rectangular openings under axial compression is considered based on the theory of shells of average thickness. For a shell with two diametrical openings, numerical calculations are carried out by the finite-difference method for anisotropic and isotropic materials. The anisotropy of the material and the sizes of the openings are shown to affect the displacements and stresses on the opening periphery. An experiment is implemented for a cylindrical shell with rectangular openings under axial compression. The experimental and numerical data are compared

Experimental Investigation of the Stress Concentration in Axially Compressed Thick Cylindrical Shells with Rectangular Holes

The stress concentration in cylindrical shells of various thicknesses is studied experimentally. The shells are made of epoxy resin, have a hole, and are subjected to axial compression. The shell thickness and the opening angle are shown to affect the stresses near the corners of the hole. The experimental and theoretical values of the stress concentration factor are compared for a thin shell

Stress state of honeycomb circular plates in uniaxial compression

Equations are derived for determining the relative density of honeycomb plates with triangular, square, hexagonal, and circular cells. The results are used to derive equations for determining the geometrical dimensions of these forms of the cells of honeycomb sheets of the equal density. The results are presented of experimental examination, by the polarization-optical method, of the stress state of elastic circular honeycomb plate with triangular, square, hexagonal, and circular cells under uniaxial compression. For specific geometrical characteristics the results of these experiments are presented in the form of fringe patterns obtained in a circular polariscope which were then used to calculate the maximum stresses at characteristic points of bridges of the honeycomb plates. For each type of structural heterogeneity of a circular plate loading was carried out in the two most typical directions coinciding with the diameter of the plate.