"INTRODUCTION This Item presents formulae for the elastic analysis of the stresses in flat laminated plates built up from thin orthotropic layers that may have different material elastic and thermal properties@ thicknesses and orientations of their principal axes of orthotropy. Stresses in laminated plates arise either as a result of externally applied loading or as a result of the method of manufacture. Current methods of production of laminated plates usually require the assembly to be cured at a temperature above the working temperature range of the plate. Upon cooling to working temperatures the different orientations of the layers together with their often different elastic and thermal properties lead to the development of a system of self-equilibrating stresses. Similarly internal stresses may be generated in plates cured at room temperature but which are subjected to a wide range of working temperatures. The formulae presented relate to uniform stress systems away from the plate boundaries or other geometric discontinuities. No allowance is made for the deformations associated with the effects of through-the-thickness shear. Methods of calculation of the stiffnesses and transformation matrices referred to extensively in this Item are provided in Item No. 94003*. The principal formulae derived in this Item are summarised in Table 8.1 * Data Item No. 94003 ""Stiffnesses of laminated flat plates""."
ESDU 94004-1994 history
1994ESDU 94004-1994 STRESS ANALYSIS OF LAMINATED FLAT PLATES