Your search resulted in 9 documents.
Decrease of stiffness properties of degraded wood predicted by means of micromechanical modeling
2011 - IRG/WP 11-40570
Wood exhibits a highly anisotropic mechanical behavior due to its heterogeneous microscopic structure and composition. Its microstructure is organized in a strictly hierarchical manner from a length scale of some nanometers, where the elementary constituents cellulose, hemicelluloses, lignin, and extractives are found, up to a length scale of some millimeters, where growth rings composed of earlyw...
T K Bader, K Hofstetter, G Alfredsen, S Bollmus
Serviceability modeling-Predicting and extending the useful service life of FRT-plywood roof sheathing
2000 - IRG/WP 00-20210
One of the most, if not the most, efficient methods of extending our existing forest resource is to prolong the service life of wood currently in-service by using those existing structures to meet our future needs (Hamilton and Winandy 1998). It is currently estimated that over 7 x 109 m3 (3 trillion bd. ft) of wood is currently in service within the United States of America (PATH 1999). Research ...
J E Winandy
Diffusion modeling of inorganic wood preservative leaching in service
2005 - IRG/WP 05-50224-5
To evaluate the potential environmental and health implications of leaching of inorganic wood preservatives in service under different conditions, there is a need for a predictive model that provides estimates of the rate and extent of leaching over a wide range of product dimensions and exposure conditions. In this paper, we show that the leaching behavior of inorganic preservative components fr...
L Waldron, P A Cooper, Y T Ung
Three-dimensional modeling of fumigant distribution in wood poles
1993 - IRG/WP 93-30025
The practice of using fumigants to control internal decay has been widely accepted in the United States and has shown to be effect in control internal decay in transmission poles and other large wood timbers. Mathematical models were developed to simulate the chloropicrin movement in utility poles after treatment. The simulation results indicated that treatment of utility poles, using either tradi...
Jing Liu, B Goodell
Adsorption of ionic liquids by Scots pine wood (Pinus sylvestris L.) and beech (Fagus sylvatica L.): equilibrium and kinetic modeling
2010 - IRG/WP 10-20447
In this paper methods for the adsorption study of quaternary ammonium-based ionic liquids on Scots pine (Pinus sylvestris L.) and beech (Fagus sylvatica L) are presented. Kinetic and equilibrium adsorption of compounds were evaluated. The equilibrium data fitted very well to the Langmuir adsorption models. The highest correlation coefficients determined from the pseudo-second order kinetic model ...
J Zabielska-Matejuk, A Stangierska, M Kot
Predicting the Rate of Decay, and the Potential for Misinterpretation of Proper Scientific Method
2013 - IRG/WP 13-20525
Predicting the rate of fungal attack in wood-based materials and its effect on properties remains the holy grail of wood products pathologists; however, achieving this goal is difficult because of the many variables associated with the process. This paper reviews some of the more important aspects of the decay process in relation to test methodology and then discusses how data are sometimes used b...
B S Goodell, J J Morrell
Cell wall properties of softwood deteriorated by fungi: combined chemical analyses, FT-IR spectroscopy, nanoindentation and micromechanical modelling
2013 - IRG/WP 13-20527
Mechanical properties of wood are determined by its inherent hierarchical microstructure, starting at the nanometer scale, where the elementary components cellulose, hemicelluloses, and lignin build up the wood cell wall material. Fungi cause degradation and decomposition of these components and, thus, alter the mechanical properties of wood. The aim of this study is to gain new insight into these...
L Wagner, T K Bader, K de Borst, T Ters, K Fackler
Design and performance prediction of timber structures based on a factorization approach
2017 - IRG/WP 17-20603
Service life of timber structures in outdoor conditions is predominantly affected by the climatic conditions in terms of moisture and temperature over time. On the one hand, the two parameters moisture content and temperature determine the exposure-induced dosage that can lead to fungal infestation and subsequent decay. On the other hand, the material resistance of wood stands in opposition to exp...
L Meyer-Veltrup, C Brischke
Multivariate modeling of mould growth in relation to extractives in dried Scots pine sapwood
2017 - IRG/WP 17-20629
Influence of extractives on mould growth on Scots pine sapwood dried in air or in kiln was studied. Boards were sprayed with water mixtures of spores of the fungal species Penicillium sp., Aspergillus sp., Mucor sp., Paecilomyces sp., Trichoderma sp., treated at a temperature of 22ºC at 90% RH, classified into a percentage of covered area. Acetone and water extracts were isolated and analyzed for...
O Karlsson, O Myronycheva, M Sehlstedt-Persson, M Öhman, D Sandberg