This study presents the correlation between laboratory and field tests in assessing the functional and aesthetic service life of the wood. The results obtained in the laboratory experiments were combined and compared with the results obtained in field trials. Thus, we evaluated the potential of various laboratory tests for the purpose of predicting the dynamics of moistening of wood in external conditions of use. To determine the correlation between laboratory and field tests, we calculated the Pearson coefficient of correlation, which determines the linear connection of two numeric variables. The results showed that it could be inferred that some faster laboratory tests can be used to predict the interaction of water with wood in external use, but a good knowledge of the conditions of use is needed. The importance of the aesthetic service life of wood is increasing and because colour is one of the most important parameters of aesthetics, we have determined and evaluated the differences in the colour changes with respect to the direction of exposure. It turned out that photo-degradation covers the signs of blue staining, and in wet months, blue staining may reappear. The results of the comparison of colour changes obtained with laboratory and field tests showed the positive Pearson correlation coefficients between natural aging of the wood and the combination of wood colouring with blue-staining fungi and artificial aging of wood. Therefore, it would be sensible to assemble a two-step laboratory test (staining with fungi and artificially accelerated aging) in order to simulate the colour changes in the best way compared to the wood tested in field trials.
|