Analysis of statistical methods for the determination of characteristic values of Italian red spruce (Picea abies)

摘要

Strength data of Italian grown spruce that has been gathered during various research projects over the last 13 years have been combined into one large dataset. The data has been analysed for mechanical properties such as bending strength, modulus of elasticity as well as density. Visual grades have been determined using the German and Italian standards and were analysed for their strength profiles. The data has been analysed for a depth effect which was found to be small at the characteristic strength level. The parameters for Normal, Lognormal and Weibull distributions have been determined. In addition to the distributions used, different methods to determine the fifthpercentile characteristic bending strength values have been used, including the method specified for Eurocode 1. This is an approach using the Bayesian method. The differences between the methods in the determination of the 5 5th th-percentile characteristic strength level were found small.