PSI - Issue 68

Victor Rizov et al. / Procedia Structural Integrity 68 (2025) 146–152 V. Rizov / Structural Integrity Procedia 00 (2025) 000–000

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The variation of the SERR generated by growth of ratio is presented in Fig. 4. The diagrams 1 and 2 in Fig. 4 correspond, respectively, to increase of delamination in the delamination tips situated in cross-sections and of the beam. There is a qualitative similarity between the two diagrams (Fig. 4). Another important finding from Fig. 4 is that the SERR for increase of delamination in cross-section is significantly higher than that for increase of delamination in cross-section . ! ! ! ! ! !

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Fig. 4. The SERR -

diagrams (curve 1 – for increase of delamination in cross-section,

, and curve 2 – for increase of delamination in

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cross-section,

).

This is explained by the rise of the values of the shear moduli of the inhomogeneous layers from the left end and towards the right end of the beam. 4. Conclusions In this paper, results from analysis of the SERR for a fixed-ended multilayered beam structure under twist of support are presented. There is an inner delamination between layers in the beam. The only external influence on the beam is the support twisting. Since the beam is statically undermined, the support twisting loads the beam in torsion that activates the delamination. Solutions of the SERR are determined for delamination increase in the left and right delamination tips. The compliance method is utilized for checking the solutions of the SERR under twisted support. Different features of the delamination associated with value of the angle of support twist, variation of the layers shear moduli along the beam length, number of layers, etc. are investigated. The investigation indicates that rise of the angle of support twist causes growth of the SERR. The increase of generates reduction of the SERR. Reduction of the SERR is observed also with growth of and ratio. The SERR for increase of delamination in its left tip is higher than that for increase of delamination in the right delamination tip. References ! ! ! ! ! ! " " ! " #

Chobanian, K.S., 1997. Stresses in combined elastic solids. Science. Dolgov, N. A., 2005, Determination of Stresses in a Two-Layer Coating. Strength of Materials 37, 422-431.