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journal of materials research and technology 2021;14:1630 e 1643
Fig. 4 e Modeling of specimens in layers: (a) mesh and detail of the layers for SL; (b) mesh and detail of the layers for ST.
strain of 0.8%, the plastic behavior was assumed [44]. A stress e strain model with three linear segments was proposed by [10] for the OSB in bending and based on experimentally obtained results, with the segments corresponding to 0 e 40%; 40 e 80%, and 80 e 100% of maximum bending force. When modeling fiberboard plates, for the bi-linear model, Haj-Ali et al. [46] adopted the compressive yield strength equal to 60% of the tensile yield strength. When adjusting the model to represent physical non- linearity, the value of the tangent modulus was obtained from the load versus deflection diagram, considering the experimental values corresponding to 60 and 100% of the maximum bending load ( P max ). In the longitudinal direction, this resulted in a tangent modulus equal to 4335.0 MPa, which, in the transverse direction, was 1193.5 MPa. In the longitudinal direction, for the value of 0.6 of the maximum bending load (0.6 P max ¼ 333.9 N), the bending moment was 18,364.5 N mm (0.6 P max Ls /4), and with an elastic section modulus of 931.18 mm 3 ( W ¼ b h 2 /6), the initial yield strength was 19.72 MPa. Based on this value, a bi- linear model with an initial yield strength of 20 MPa was implemented (sigma20 model, Fig. 6(a)). This model, despite already accounting for the effects of non-linearity, had a much more rigid behavior compared to the experimental re- sults. To adjust the model, the final displacement becomes more representative of the experimental value with an assumed initial yield strength of 10 MPa (sigma10 model). The multi-linear model is an interesting solution to better represent elastic e plastic behavior, and thus, resolve the dif- ferences found in the bi-linear models (sigma20 and sigma10). For the Mult_sigma15 model (Fig. 6(a)), implemented based on
attempts at adjustment, the following points (strain and stress) were assumed: (0; 0); (0.002202; 15); (0.00336; 20); (0.01;
Fig. 5 e Load-deflection models of the OSB material: (a) SL specimen; (b) ST specimen.
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