Conclusions
1. When short beams made of composite materials with span-to-height ratios within the 4.0–5.0 range are tested in three-point flexure, the profile of shearing stresses over the height of a beam cross section departs appreciably from a parabolic one over approximately 40% of the span length.
2. The zones of a perturbed state of stress, which appear in short beams tested in three-point flexure, render this method unusable for determining the interlayer shear strength of composite materials on "ultrashort" specimens.
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Institute of Polymer Mechanics, Academy of Sciences of the Latvian SSR, Riga. Translated from Mekhanika Polimerov, No. 1, pp. 56–62, January–February, 1977.
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Tarnopol'skii, Y.M., Zhigun, I.G. & Polyakov, V.A. Distribution of shearing stresses under three-point flexure in beams made of composite materials. Polymer Mechanics 13, 52–58 (1977). https://doi.org/10.1007/BF00857280
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DOI: https://doi.org/10.1007/BF00857280