Wood is a natural material that is being increasingly used in engineering structures due to greater environmental awareness. The problem with using wood, however, is that it begins to gradually degrade when exposed to the weather, which can express e.g. in cracking. Since cracks, especially on the supporting elements of larger dimensions, can weaken their strength and affect their appearance, we try to avoid them which requires a good knowledge of the mechanics of wood drying processes. The study deals with the effects of wood shrinkage due to the drying process on the stress field that is induced during this process. The effect of polar orthotropy, which is the result of tree growth, is highlighted. A mathematical model based on the finite element method takes into account the change of moisture distribution across the cross-section over time and the formation of stress due to the resulting shrinkage. A convection drying boundary condition is used. The algorithm is capable of predicting the locations of maximum values of tensile stresses and the propagation of cracks in the round and square cross-section of a wooden element.
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