COMPARATIVE ANALYSIS OF THE TYMOSHENKO METHOD AND THE Γ-METHOD FOR CALCULATION OF CLT PANELS STRENGTH BY BENDING.
DOI:
https://doi.org/10.31618/ESSA.2782-1994.2021.2.71.91Keywords:
bending strength, cross laminated timber, CLT, calculation method, shear deformation, Timoshenko beam theory, shear coefficient, shear stiffness, γ-method, advantages and disadvantages.Abstract
The γ-method and the Timoshenko method are most often used for calculation the bending strength of CLT panels, the latter of which takes into account the transverse shear deformations of the transverse layers of boards, which are due to the significant difference between the modulus of elasticity and the shear modulus apply the method of Timoshenko's beams. The γ-method treats the CLT panel as a beam on flexible joints, similar to the Derevyagin system beam on plate dowels or Kubler cubes, where the transverse layers of the boards are considered as flexible joints and are not taken into account when calculating the geometric characteristics of cross sections of CLT panels. Taking into account the amount of shear for each type of panels, depending on the configuration of the cross-sectional components, is performed by introducing shear correction factors, which in turn depend on the thickness of the CLT panel layers and their distance from the center of gravity of the panel. The γ-method, like Timoshenko's method, is used in engineering practice more often than the shear analogy method. Each technique has its advantages and disadvantages, as it has a number of specific assumptions to simplify the calculations. This paper highlights the advantages and disadvantages of the γ-method and the Timoshenko method, which are the most common and are contained in many technical opinions of various manufacturers of CLT panels.
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