In this thesis, we focused on the dynamic loads that are often encountered during the use of wood. Wherever timber is used as a load-bearing or structural element, it can be exposed to adverse weather (wind) or dynamic environments (vibrations), which can lead to fatigue over time. In addition to the effect of the loading force, we also focused on the effect of the frequency of repetition of the loading over a given period of time, represented by the frequency of loading. We compared frequencies of 5 and 10 Hz, and for each of these we determined three orders of magnitude of the loading force. The tests were carried out on spruce (Picea abies). We found that the magnitude of the loading force within the same frequency has a significant influence, since with each increase in loading force the dynamic strength of the pine wood decreases, which is reflected in the load cycles achieved. Dynamic properties also deteriorate with increasing loading frequency, which is more pronounced at higher loading forces. Due to the large scatter of results, a larger number of samples would be needed. However, we had to limit the number of samples because fatigue tests are very time-consuming.
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