Abstract:

ESDU 93011 introduces a Fortran program which gives (i) the detailed distribution of deflection and either the moments and in-plane forces, or the stresses, or the strains, throughout the plate for a given pressure load or (ii) the maximum deflection and the peak values of moments, forces, stresses and strains and their location for a range of pressure loads. The differential equations formed in terms of stress and displacement functions apply to elastic, large deflection, moderate rotation, thin plate theory and are solved by a finite difference technique for edge conditions of elastic rotation, translation or shear restraint. The plate must be specially-orthotropic, is considered homogeneous, is rigidly restrained in its own plane, and its properties are input as in-plane and flexural stiffness matrices. The plate is treated as symmetrical and so behaviour in one quarter only is considered with a grid chosen by the user of 4x4, 6x6 or 8x8 points. Output of the distributions can be chosen to be at every point or at alternate points. The program input and output are fully described, error messages that may be output are explained, and a worked example illustrates its use. The program is available as ESDUpac A9311.