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Strength and deformation properties of fiberglass-plastic in the flat stressed state as a function of reinforcement structure

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Limiting strength values have been ascertained in the flat stressed state as a function of reinforcement structure. The change in each strength surface tensor component as a function of reinforcement intensity has been approximated by the piecewise-linear approximation method. A strength condition has been derived which can be used in optimization problems. The problem of the optimum reinforcement structure of a composite at various ratios of the stresses σ11, σ22, and σ12 has been examined. By using the strength condition, one can predict strength values for structures which appear in the class of materials in question with various reinforcement intensities. The procedure developed can be used in designing composite materials.

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Additional information

Institute of Polymer Mechanics, Academy of Sciences of the Latvian SSR, Riga. Translated from Mekhanika Polimerov, No. 5, pp. 848–859, September–October, 1978.

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Upitis, Z.T., Rikards, R.B. Strength and deformation properties of fiberglass-plastic in the flat stressed state as a function of reinforcement structure. Polymer Mechanics 14, 681–691 (1978). https://doi.org/10.1007/BF00860783

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  • Stressed State
  • Composite Material
  • Approximation Method
  • Reinforcement Structure
  • Tensor Component