Probabilistic Modelling of Timber Material Properties

The probabilistic modeling of timber material characteristics is considered with special emphasis to the modeling of the effect of different quality control and selection procedures used as means for grading of timber in the production line. It is shown how statistical models may be established on the basis of the same type of information which is normally collected as a part of the quality control procedures and furthermore, how the efficiency of different control procedures may be compared. The tail behavior of the probability distributions of timber material characteristics play an important role in the overall probabilistic modeling. Therefore a scheme for estimating the parameters of probability distribution parameters with special focus on the tail behavior has been established using a censored Maximum Likelihood estimation technique. The proposed probabilistic models have been formulated such that they may readily be applied in structural reliability analysis and the format appears to be appropriate for codification purposes of quality control and selection for grading procedures