Your search resulted in 224 documents. Displaying 25 entries per page.
Moisture correction for ultrasonic MOE measurements above fibre saturation point in Scots pine sapwood
2006 - IRG/WP 06-20333
There is a high correlation between methods for dynamic modulus of elasticity (MOEdyn) and static modulus of elasticity (MOEstat). MOEdyn methods have been found sensitive to detect early stages of decay and may be seen as an option for non-destructive wood durability testing. As the MOEstat measurements do not change after reaching the fibre saturation point, the uncorrected MOEdyn data from ultr...
E Larnøy, G Alfredsen, H Militz
Laboratory methods for assessing the resistance of wood plastic composites to fungal attack.
2006 - IRG/WP 06-20340
Wood plastic composites (WPC’s) have many attractive material features including dimensional stability and resistance to moisture, but the wood in these materials remains susceptible to fungal attack. Assessing WPC decay resistance in laboratory trials has proven difficult because the slow moisture sorption characteristics of this material do not allow for sufficient fungal attack over the trad...
J J Morrell
CCB Preservative treatment of split muli (Melocanna baccifera ) bamboo by soaking process
2006 - IRG/WP 06-40336
This study was carried out in order to investigate the retention of chemicals inside the split muli ( Melocanna baccifera ) bamboo after preservative treatment by soaking process. Treatment with 10% aqueous solution of CCB (copper-chrome-boron) was applied in split bamboo of two sizes (1/4 part and 1/8 part) at three different moisture contents and five time periods (24, 48, 72, 96, 120 hours). It...
K Akhter, M H Chowdhury
The Influence of Extractives on Western Redcedar’s Equilibrium Moisture Content
2006 - IRG/WP 06-40331
The high natural durability of western redcedar (Thuja plicata Donn) heartwood is often attributed to the presence of the thujaplicins, which are toxic to fungi. However, sound, twenty-five year old western redcedar shakes and shingles were found to contain only traces of the thujaplicins, but significant quantities of plicatic acid (which is only weakly toxic to fungi). This suggests that factors...
R Stirling, P I Morris
Lyctine susceptibility testing and dealing with rarely susceptible hardwood species
2007 - IRG/WP 07-10607
This study examined the lyctine susceptibility of 16 timber species or hybrids. Several of the timbers have been placed previously in a ‘rarely susceptible’ category, but for standards and compliance purposes, such in-between ratings are not acceptable. Timber specimens were spot tested for starch content, and exposed to three species of lyctine beetles in an insectary. New criteria were devel...
L J Cookson, J Carr, N Chew, J W Creffield
The effect of wood moisture content and rod dosage on movement of boron through Douglas-fir heartwood
2007 - IRG/WP 07-30431
The potential for moisture sorption by boron rods following application to wood to affect subsequent boron diffusion was investigated in small Douglas-fir blocks conditioned to 30, 60 or 90% moisture content (MC). MCs tended to decline over the 180 day test period, but there was no evidence that the rods acted to draw moisture away from the wood. As expected, boron movement tended to increase with...
Y Cabrera, J J Morrell
Effect of barriers on moisture content of treated and non-treated utility poles
2007 - IRG/WP 07-40369
The potential for non-biocidal barriers to slow moisture sorption was investigated using butt treated western redcedar poles immersed in either water or moist soil over a 2 year period. Moisture sorption was initially slowed by the barriers, but openings at the bottoms of the barriers eventually allowed moisture to migrate upward. Moisture levels in wrapped poles eventually reached those found in...
C S Love, J J Morrell
The Role of Moisture Content in Above-ground Leaching
2007 - IRG/WP 07-50245
This paper reviews previous reports on the moisture content of wood exposed above ground and compares those values to moisture contents obtained using simulated rainfall and immersion methods. Laboratory leaching trials with CCA-treated specimens were also conducted and the results compared to published values for leaching of CCA-treated specimens exposed above ground outdoors. Previous researcher...
S Lebow, P Lebow
Control of Moisture Content in Wood Materials for Mold Growth
2007 - IRG/WP 07-10630
Mold growth on wood materials is a major concern for house owners, as it can cause health and aesthetic problems. Mold fungi, present everywhere, usually appear as black or gray patches on wood surfaces in humid environments, and are common in houses. Like any living organism, molds need food, water, oxygen, and a specific temperature range in order to grow. To avoid mold growth on wood materia...
Dian-Qing Yang
Effect of fiber type and content on the natural durability of wood flour/high density polyethylene composites against rainbow fungus (Coriolus versicolor)
2007 - IRG/WP 07-40387
In order to evaluate the effect of fiber type and content on the natural durability of wood flour/high density polyethylene (HDPE) composites against Coriolus versicolor, samples containing 25% and 50% by weight of various natural fibers and HDPE were selected. Natural fibers included in the study were wood flour, rice hulls, hemp fibers and newsprint. Samples containing 25% and 50% natural fiber ...
A Karimi, M Tajvidi, S Pourabbasi
Preservative treatment of strips of Bambusa balcooa by soaking process using Borax-Boric acid
2008 - IRG/WP 08-30478
Bamboo strips made from Borak bamboo (Bambusa balcooa) were treated with 10% borax-boric acid aqueous solution by soaking process. The moisture contents of the bamboo strips were 12%, 20% and 30%. The strips were soaked for one, two, three, four and five days. The penetration of the
solution was investigated by colour test after soaking and drying. Full penetration was observed after three days ...
K Akhter, M W Sheikh, M M Rahman, T A Chowdhury, M H Chowdhury
Effects of acetic acid and nitric acid pre-treatment on copper content of spruce wood treated with CBA-A and CCA
2008 - IRG/WP 08-40406
This work investigates the effects of nitric acid and acetic acid on compression strength values and copper retention contents of refractory spruce wood (Picea oriental L.) treated with the waterborne preservative Copper azole, (CBA-A, Tanalith-E 3492) and copper / chrom / arsenic (CCA). Before the CBA-A and CCA treatment, the samples were immersed in 500 ml of nitric and acetic acid solutions for...
S Yildiz, E Dizman, Ü C Yildiz
Effects of Moisture Content and Species on Penetration of Liquid in Laser Incised Lumber by the Passive Impregnation Method
2008 - IRG/WP 08-40408
Penetration of liquid by passive impregnation method for Douglas-fir (Pseudotsuga menziesii Franco), sugi (Cryptomeria japonica D. Don) and Japanese larch (Larix leptolepis Gordon) were studied. Effects of initial moisture content of sugi (16, 43 and 70% moisture content) on liquid penetration by the method were also studied. Dried Douglas-fir and sugi, and green Japanese larch and sugi were treat...
N Hattori, M Nazrul Islam, K Ando, H Yamauchi
Comparison of permeability at different levels of moisture content in Bornmullerian fir (Abies bornmulleriana Mattf.) and Eastern spruce (Picea orientalis L.) impregnated under vacuum/pressure through full-cell method by using CCA and CCB of different concentrations
2007 - IRG/WP 07-40366
In this study, a comparison has been made in terms of the combined, longitudinal, tangential, and radial permeability of the species of Bornmullerian fir (Abies bornmulleriana Mattf.) and Eastern spruce (Picea orientalis L.) with moisture contents of 50 % and 15 %, which were impregnated under vacuum/pressure through full-cell method by using water-borne wood preservatives (impregnation materials)...
I Usta
High Temperature Treated Wood
2008 - IRG/WP 08-40429
High temperature can modify internal structure and physic-chemical properties of wood by a controlled pyrolysis process. Such treatment, among other changes in properties, modifies the wood color in a way that resembles exotic species, increasing its market value. The main objective of this work is to determine the changes in wood properties caused by the effect of temperature and time, in order t...
C C Borges, A L Barbosa, R Faber de Campos, S T Targas
Service Life Prediction of Wood Claddings by in-situ Measurement of Wood Moisture Content: Status after 5 years of Outdoor Exposure
2009 - IRG/WP 09-20401
The Danish Technological Institute is in co-operation with industry partners running a project aiming at predicting the service life of different wood protecting systems. The project focuses on examining the moisture reducing effect of different protecting systems for timber claddings and the ability of these to maintain the appearance of the surfaces, when the wood is used in service class 3 (EN ...
E Tang Engelund, B Lindegaard, N Morsing
Evaluation of variables that influence dynamic MOE in wood decay studies
2009 - IRG/WP 09-20409
The effect of wood moisture content (MC) and outdoor exposure of southern pine lap-joint components on dynamic MOE values was investigated. The use of dynamic MOE as a method of measuring progressive biodeterioration of above ground test samples shows promise, but the accuracy of this method for evaluating test samples subjected to fluctuating environmental conditions has not been reported. The re...
D Nicholas, J Shi, T Schultz
Fungal decay resistance and durability of wood products made from borax-impregnated wood and bonded with corn starch and tannin adhesive
2009 - IRG/WP 09-30494
At present, the production of wood composites mainly relies on the petrochemical-based and formaldehyde-based adhesives such as phenol formaldehyde (PF) resins and urea formaldehyde (UF) resins, which are non-renewable and therefore ultimately limited in supply. This paper concerns the decay resistance of wood products bonded with a new, environment-friendly adhesive derived from abundant and rene...
A Moubarik, A Pizzi, A Allal, F Charrier, B Charrier
Estimating the heat treatment intensity through various properties of thermally modified timber (TMT)
2009 - IRG/WP 09-40459
The suitability of different measures for prediction of the heat treatment intensity was investigated. Therefore, the resistance to impact milling (RIM), the lightness L*, the equilibrium moisture content (EMC), the anti swelling efficiency (ASE) and the total amount of soluble carbohydrates (TSC) of heat treated specimens were correlated with corresponding fungal resistance achieved by heat treat...
C R Welzbacher, C Brischke, A O Rapp
Weathering of Wood Modified with the N-Methylol Compound 1,3‑dimethylol-4,5-dihydroxyethyleneurea (DMDHEU)
2009 - IRG/WP 09-40467
Scots pine (Pinus sylvestris L.) sapwood boards were treated with a methylated 1,3‑dimethylol-4,5-dihydroxyethyleneurea (mDMDHEU) causing weight gains of approx. 25% and exposed to weathering for 18 months. Compared to untreated boards, treatment with mDMDHEU reduced surface discoloration mainly caused by staining fungi. Boards treated with mDMDHEU exhibited clearly lower moisture content th...
C Mai, Yanjun Xie, A Krause, K Urban, P D Evans, K Richter, H Militz
Wood properties influencing the penetration of Scots pine (Pinus sylvestris) sapwood with the wood modification agent furfuryl alcohol
2009 - IRG/WP 09-40470
The European standard EN 350-2 classifies Scots pine sapwood as class 1 (easy to treat). However large variations in sapwood penetration exist which affect a homogenous distribution of preservatives. Hence individual penetration schemes have to be developed and adjusted to the material most difficult to treat in order to provide adequate sapwood penetration. To ensure better economic process con...
K Zimmer, E Larnøy, G Koch
Measurements of rot fungal activity as a function of moisture content by isothermal calorimetry
2010 - IRG/WP 10-20428
Measurements of heat production rate have been made on wood samples with the brown rot fungus Postia placenta at different moisture contents. The results clearly indicate that the heat production rate (a measure of respiration rate and activity) is moisture dependent. When the moisture content is decreased, less heat is produced, and when the moisture content is increased, more heat is produced. I...
L Wadsö, A Pilgård, G Alfredsen
Service life prediction of wooden components – Part 1: Determination of dose-response functions for above ground decay
2010 - IRG/WP 10-20439
Scots pine sapwood (Pinus sylvestris L.) and Douglas fir heartwood (Pseudotsuga menziesii Franco) specimens were exposed in double layer field trials at 24 different European test sites under different exposure conditions (in total 28 test sets). The material climate in terms of wood moisture content (MC) and wood temperature was automatically recorded over a period of up to eight years and compar...
C Brischke, A O Rapp
Impact of climate change on wood deterioration - Challenges and solutions for cultural heritage
2010 - IRG/WP 10-20441
Deterioration of wood in cultural assets follows the same physiological mechanisms as in modern structures. Therefore rules and data for prediction of service life derived from old wooden structures can be used to model the service life of recent wooden structures and vice versa. The latter is done in this paper: From experimental test set ups in the field spread over Europe, climatic data, wood t...
C Brischke, A O Rapp, M Hasan, R Despot
A Review on Conditions for Decay Initiation and Progression
2010 - IRG/WP 10-20444
This paper reviews the key publications available on service life prediction of exterior wood applications, critical conditions for decay initiation and progression, and the impact of decay on wood strength. While it is helpful to use climatic data to predict general trend of decay potential, more precise decay initiation and progression information is required by hygrothermal modeling for its dam...
Jieying Wang, P I Morris