Due to its hygroscopic and time-dependent nature, wood is susceptible to the development of long-term deformations. This master’s thesis investigates the influence of selected rheological and mechanical parameters on the long-term mechanical response of a glued laminated timber beam subjected to variable climatic conditions. A numerical model is used in which the first phase determines the temporal and spatial development of temperature and moisture content within the beam cross-section, while the second phase evaluates the mechanical response of the beam by accounting for elastic deformation, shrinkage and swelling, viscoelastic creep, and mechano-sorption. A parametric study was carried out in which individual input parameters were varied separately, and their influence was evaluated based on displacements, the deformation factor, individual deformation components, and stresses within the cross-section. The results showed that, among the rheological parameters considered, the mechano-sorptive parameter has the greatest influence, followed by the creep parameters with a less pronounced effect, while the shrinkage coefficient has the smallest influence within the investigated range. The modulus of elasticity also has a significant influence, particularly on the initial and total displacements as well as on the value of the deformation factor. The results confirm the importance of appropriately determining input parameters for reliable prediction of the long-term response of timber structures.
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