The combined effect of wetting ability and durability on outdoor performance of wood: development and verification of a new prediction approach

Abstract

Meyer-Veltrup et al.: The combined effect of wetting ability and durability on outdoor performance of wood -development and verification of a new prediction approach Abstract Comprehensive approaches to predict performance of wood products are requested by international standards and the first attempts have been made in the frame of European research projects. However, there is still an imminent need for a methodology to implement the durability and moisture performance of wood in an engineering design method and performance classification system. The aim of this study was therefore to establish an approach to predict service life of wood above ground taking into account the combined effect of wetting ability and durability data. A comprehensive data set was obtained from laboratory durability tests and still ongoing field trials in Norway, Germany, and Sweden. Supplementary, four different wetting ability tests were performed with the same material. Based on a dose-response concept decay rates for specimens exposed above ground were predicted implementing various indicating factors. A model was developed and optimised taking into account the resistance of wood against soft, white and brown rot as well as relevant types of water uptake and release. Decay rates from above ground field tests at different test sites in Norway were predicted with the model. In a second step the model was validated using data from lab and field tests performed in Germany and Sweden. The model was found to be fairly reliable and it has the advantage to get implemented into existing engineering design guidelines. The approach at hand might furthermore be used for implementing wetting ability data into performance classification as requested by European standardisation bodies.

The minimum moisture threshold for wood decay by basidiomycetes revisited. A review and modified pile experiments with Norway spruce and European beech decayed by Coniophora puteana and Trametes versicolor

“…MMThr and other physiological requirements of decay fungi are usually tested in laboratory experiments (Viitanen 1997;Viitanen et al 2010), and also in the field (Scheffer 1971;Augusta 2007; Van den Bulcke et al 2009;Meyer-Veltrup et al 2017). It is agreed that available free water in the cell walls is critical, but not that in the cell lumens Stienen et al 2014).…”

Utilisation of chemically modified lampante oil for wood protection

“…This would provide us with a more realistic view of the antimicrobial and fungal performance of the wood/oil treatment specimens rather than simply creating a hydrophobic oil barrier. However, recent studies clearly indicate that water exclusion efficacy contributes to the overall performance of wood in outdoor applications (Meyer-Veltrup et al 2017) and the hydrophobic effect cannot be neglected. Additionally, the effect of oil products in culture media on fungal growth could be investigated, where radial growth in a Petri dish is recorded (Paajanen and Ritschkoff 2002).…”

“…This property could be used to predict field performance of wood (Meyer-Veltrup et al 2017). However, the absence of a biocidal effect from the oil treatment makes long-term durability unlikely.…”

Evaluation of the wood degradation in the underground fort Goli vrh

“…V primerljivih, a nekoliko bolj toplih pogojih je les v Partizanski bolnici Franja propadel po približno petih letih . Na življenjsko dobo lesa poleg naravne odpornosti v največji meri vpliva še vlažnost okolja in temperatura (Meyer-Veltrup et al, 2017). Namen prispevka je raziskati mikroklimatske pogoje v podzemni utrdbi in oceniti razkrojenost lesa.…”