Abstract: | In [5–7], the influence of the relation between the plate width and the crack length on the limiting load for steel was investigated. The hazardous defect dimension in steel is determined by the grain size, and may be neglected in practice. For molding compositions reinforced by glassfiber or glass-strip sections, the hazardous defect dimension may be comparable with that of a visually observable crack. In that case, the failure criterion and the scale effect for a cracked plate depends on the relation between the plate width and the crack length, and on the crack-resistance characteristic of the material, which is the length of the crack equivalent to the hazardous defect in the material. The aim of the present work is to investigate this characteristic experimentally in various loading conditions, for the example of AG-4V molding composition and to develop a simple model permitting the prediction of the scale effect in analogous materials.S. P. Timoshenko Institute of Mechanics, Ukrainian Academy of Sciences, Kiev. Translated from Prikladnaya Mekhanika, Vol. 30, No. 1, pp. 62–67, January, 1994. |