A discussion on the control of grading machine settings

Authors

Jochen Köhler and René Steiger

Abstract

Typical problems in structural engineering such as design, assessment, inspection and maintenance planning are decision problems subject to a combination of inherent, modelling and statistical uncertainties. Recent developments in the field of structural reliability together with the formulation of probabilistic models for the structural response and for loads enable the structural engineer to quantify these uncertainties and establish his decisions on a consistent basis. The results of these advances are summarized in the Probabilistic Model Code (PMC) published by the Joint Committee on Structural Safety (JCSS).
The PMC contains general guidelines for uncertainty modelling, reliability assessment and probabilistic models for loads and material resistance for building materials as concrete and steel. Lately, also a probabilistic model code for structural timber has been developed by an international group of researchers organized under the umbrella of the COST action E24 Reliability of Timber Structures. During the COST action E24 it has become apparent that several fundamental issues require more research and development. In particular it has been found that the present practice in regard to strategies to quality control or grading of timber raw material introduces significant uncertainties on the performance of timber structural components. In the present paper control schemes for timber grading machines are discussed from the perspective of the probabilistic modelling of material properties of graded timber.

Published by/in

Proceedings of CIB-W18, Paper No. 39-5-1, Florence, Italy, August 28-31, 2006.