1636
journal of materials research and technology 2021;14:1630 e 1643
Mult_sigma7.6 models were investigated, which include the maximum experimental displacements. For this purpose, the stress versus strain diagrams were modified based on the ratio of the moduli of elasticity ( E LL / E L ¼ 1.05and E TL / E T ¼ 0.79) that were applied to the stress values (Mult_layer model, Fig. 8).
3.
Results and discussion
The results concerning the rigidity obtained by the OSB models used in the computer simulations were evaluated based on the flexural rigidity of the specimens in the bending test. Additionally, due to the proposed use of the equivalent moduli of elasticity attributed to the OSB panel layers, the effects in the normal bending stress were also evaluated. To validate the model discretized by SHELL181 elements (Fig. 3), the analysis of convergence was evaluated for several generated meshes by varying the number of nodes and ele- ments. The results in Table 1 summarize the values of the deflections in the elastic-linear analysis for the maximum loads ( P max ) of 556.5 N (for SL) and 205.3 N (for ST), which were applied to three key points (2 edge points and 1 center point) positioned at the middle of the span of the specimen (Fig. 3). Based on the results of the convergence of vertical displace- ments with centesimal precision (Table 1), the mesh of the elements with dimensions of 2.5 mm was chosen for modeling for both directions.
Fig. 8 e Stress versus strain adjusted with physical non- linearity and applied to the Mult_layer model: (a) longitudinal direction; (b) transverse direction.
( 2 ð I e Þ E LL þ I i E TL ¼ I E L I i E LL þ 2 ð I e Þ E TL ¼ I E T
(1)
where I e is the moment of inertia of each outer layer, I i the moment of inertia of the core layer, I the moment of inertia of full cross-section, E L and E T the modulus of elasticity obtained from the bending test with the length of the specimens aligned in the longitudinal and transverse directions, respec- tively, E LL the equivalent modulus of elasticity of the longitu- dinal layer and E TL the equivalent modulus of elasticity of the transverse layer. As the resolution of the linear system results only in elastic properties, to consider the effects of non-linearity of the ma- terial, the adjustments for the Mult_sigma19.7 and
Table 1 e Mesh attributes and maximum vertical displacements for SL and ST specimens, corresponding to P max . Elements Deflection (mm) Dimension (mm) Quantity SL ST
20 10
48
3.66 3.67 3.70 3.70 3.70
5.52 5.55 5.56 5.57 5.57
132 440
5
Fig. 9 e Deflection as a function of the step of maximum loads for the various models tested: (a) longitudinal direction; (b) transverse direction.
2.5
1760
1
10,560
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