Your search resulted in 662 documents. Displaying 25 entries per page.
Natural durability, density and extractive contents of 42 wood species of Bangladesh.
2003 - IRG/WP 03-10490
Natural durability, density and major extractive contents of 42 lesser used or unused wood species of Bangladesh have been studied. Correlation analysis between these properties has been performed. It has been shown that natural durability of these species neither explained by water soluble nor by alcohol benzene extractive contents. Density has a weak but significant positive correlation with dur...
S Akhter, K Akhter, S C Das
Resistance of various wood species against decay by Coniophora cerebella (Pers) Duby and Lenzites trabea (Pers) Bres
1976 - IRG/WP 142
Both fungi, Coniophora cerebella and Lenzites trabea, are important destroyers of timber. Coniophora often occurs inside buildings and Lenzites trabea has been observed on southern facades of buildings, on balconies and window frames. In most instances that we investigated coniferous timber had been decayed. But both species are known to attack also various hardwoods. For this reason tests similar...
O Wälchli
Natural resistance of timbers to marine borer attack. A laboratory test with Limnoria tripunctata
1977 - IRG/WP 430
Attack of the timber specimens was much less severe in the laboratory than in some marine localities. This is not surprising. One reason is certainly that wood-boring molluscs (Teredinidae and Pholodidae) which were missing in the laboratory are the most important wood-destroying organisms in the open sea. Another reason is that it is not possible to offer the gribbles optimal environmental condit...
H Kühne
Evaluation of chlorpyrifos and fungicides alone and in combination for control of insects and fungi in wood and wood composites
1998 - IRG/WP 98-30187
Wood composites are rapidly being adapted for use in exterior applications. The incorporation of a preservative system to prevent fungus and insect attack is necessary with most exterior composites. Research studies were reviewed pertaining to organic preservative systems based on Lentrek* insecticide wood treatment which contains the active ingredient chlorpyrifos alone and in combination with te...
M P Tolley, P E Laks, R Fears
Evaluation of wood durability by laboratory test - A new equation to predict wood durability
2001 - IRG/WP 01-20230
To estimate the wood durability in a short term, periodical weight determination was carried out in a laboratory test. This test provided the results comparable to those of the field test and the fungus cellar test, but it required much more jobs in comparison to the usual accelerated laboratory test. To save the time and jobbing for this method, a new equation was devised from simple two assumpti...
I Momohara, K Yamamoto
The natural durability assessments of secondary timber species - field trials
1998 - IRG/WP 98-10297
Secondary or 'alternative' hardwood timber species can replace traditional hardwoods and contribute significantly to satisfying the overall demand for hardwoods in the UK timber market. A selection of these 'alternative' hardwoods is currently being tested at BRE-WTC for natural durability both in ground contact (to EN252) at two field sites, and out of ground c...
E D Suttie, R J Orsler
Eucalyptus globulus. Impregnability in relation with plantation and crop
1992 - IRG/WP 92-2402
Eucalyptus globulus Lasill is currently classified in Pr EN 350 on the basis of the characteristics of the first log. In practice, there are usually several following crops of branches developped on each stump in plantations. Up to a diameter of 8 cm, round wood of 2nd crop and further crops present a maximum of sapwood and characteristics which differ significantly from the basic classification a...
D Dirol
Treatability and natural durability of some lesser used or unused wood species of Bangladesh
2000 - IRG/WP 00-40170
A research study was conducted to determine the natural durability and treatability of heartwood of some lesser used or unused wood species. The treatability of species has been studied along with certain anatomical concepts association with preservative penetrability of the wood. It was observed that grain structure and presence of tyloses appeared to be correlated with penetrability of the wood....
K Akhter, M Younusuzzaman, M H Chowdhury
The influence of the location of a wood defect on the modulus of elasticity determination in wood durability testing
2004 - IRG/WP 04-20287
This study investigates the influence of the location of a wood failure in stakes upon elastic changes observed in beech specimens with the resonance vibration technique. Natural failures were simulated by artificially created defects at different locations of the test stake. The results indicate that the location of an attack in a stake is important for the measurement outcome. When the attack is...
L Machek, H Militz
Variation in natural durability of British grown Douglas fir ((Pseudotsuga menziesii (Mirb.) Franco). Part I. Effect of density and growth rate
2002 - IRG/WP 02-10445
Seed origin trials of Douglas fir (Pseudotsuga menziesii) in Britain have provided important information on growth differences between origins (Lines, 1987), but the variation in wood properties between origins has not been reported. The present paper describes a study of the variation in natural durability against two brown rot fungi (Coniophora puteana and Postia (Poria) placenta) and in a fung...
S Akhter, M D C Hale
Preservative treatment of different thatching materials for low cost housing
1999 - IRG/WP 99-40144
Preservative treatment were made in seven different roofing materials with Copper-Chrome-Boron (CCB) at different concentration by soaking process. These were paddy straw, wheat straw, jute stick, sungrass, ulu grass, sugercane leaf and Nipa fruticans. It was observed that retention of preservative chemicals varies from species to species at the same concentration. From the service test it was obs...
K Akhter, M Younusuzzaman, M H Chowdhury
Durability of Anogeissus acuminata timber used for plank-built catamarans
2005 - IRG/WP 05-10551
Catamaran, the most versatile traditional fishing craft used along the Indian coast is made hitherto of solid timber of a few selected species of broad-leaved soft woods. Due to scarcity coupled with high cost of these timbers, the craft, of late, are fabricated from the wooden planks of an indigenous hardwood species, namely, Anogeissus acuminata (Yon) belonging to the family Combretaceae. Infor...
M V Rao, M Balaji, V Kuppusamy, K S Rao
Influence of felling time on the natural durability of norway spruce (Picea abies (L.) Karst.)
1998 - IRG/WP 98-10250
Natural durability was tested in a laboratory test according to EN 113. The test fungi were Coniophora puteana and Poria placenta. Additionally, the test method was modified by using water agar instead of malt agar, so that wood was the only nutrient source for the fungi. In a third attempt the samples were inoculated with Trichoderma harzianum before testing.
The trees were felled on the 22.7.97...
M Hirmke, K Messner, J Fellner, A Teischinger, R Wimmer
Natural durability of fifty species of Indian timber in Goa waters against marine wood-borers
1989 - IRG/WP 4150
Results of the investigations on the natural durabilitv of fifty species of Indian timber, based on data collected bv exposing test panels at Betim near Panaji (Goa) continuously for a period of 11 months are presented. The study revealed that none of the timber species tested has any natural resistance at this locality and all the panels were completely destroyed within 11 months. Details on the ...
L N Santhakumaran, S Udaya Bhaskar, J C Jain
A comparison between different accelerated test methods for the determination of the natural durability of wood
1996 - IRG/WP 96-20099
According to the European standard EN 350-1 the natural durability of wood is defined as: "the inherent resistance of wood to attack by wood destroying organisms". This standard also describes how, for certain hazard classes, the durability is determined. The two methods described in this standard are the kolleflask method (EN 113) and the field-stake-test method (EN 252). The EN 113 test gives re...
H Militz, S G L Michon, J E Polman, M Stevens
Performance of preservative-treated timber against biodeterioration in Indian waters
1984 - IRG/WP 4106
Results on the investigation on the durability of panels of 32 timber species, pressure-treated with various preservatives and exposed along the Indian coast for varying periods upto a maximum of 15 years, are summarised. Panels of even non-durable timber gave excellent results against biodeterioration after treatment. Their life was comparable to that of treated durable timber. The preservative t...
L N Santhakumaran, J C Jain, M C Tewari
NIR spectroscopy for rapid estimation of decay resistance
2004 - IRG/WP 04-20294
In Scandinavia Scots pine (Pinus sylvestris L.) is an important commercial tree species. Its heartwood has traditionally been used in constructions exposed to risk of decay. In a laboratory experiment Scots pine wood specimens sampled from inner heartwood, outer heartwood and sapwood were exposed to the brown rot fungus Poria placenta. In general outer heartwood was more resistant than inner heart...
P O Flæte, E Ystrøm Haartveit
Evaluation of the european standard ENV 12038 for durability testing of plywood
2001 - IRG/WP 01-20237
The latest improved version of the standard ENV 12038 drafted as document N44 by CEN Technical Committee 38 (WG 7 - WG 23) is used to evaluate the effect of wood composition and structure on plywood durability. The method described is based on the agar-block test of the EN 113 standard used for the determination of the efficacy of wood preservatives and the assessment of the natural durability of ...
J Van Acker, M Stevens, E De Clercq
Soft Rot Decay of Cengal (Neobalanocarpus heimii) Heartwood in Ground Contact in Relation to Extractive Microdistribution
2003 - IRG/WP 03-10501
The heartwood of cengal (Neobalanocarpus heimii, fam. Dipterocarpaceae) is naturally durable. A square-sawn utility pole specimen of cengal heartwood, after 30 years in ground contact, showed 10-15 mm surface decay all around the ground line position, accompanied with isolated surface termite attack at the decayed region. Light and transmission electron microscopy (TEM) of the decayed regions prov...
A P Singh, A H H Wong, Yoon Soo Kim, Seung-Gon Wi, Kwang Ho Lee
Durability of surface coating systems. Mycologg - an accelerated mycological test.
2004 - IRG/WP 04-20301
Field testing and natural aging/degradation of test sample, e.g. coated wooden surfaces is a slow process. Accelerated tests focus on mechanical properties, water uptake or sometimes stain fungi.
Artificially weathered coated panels are not easily compared with naturally aged panels, and show the importance of involving the biological component among the degrading facors. It is a need for acce...
L Ross Gobakken, J Mattsson, B Jacobsen, F G Evans
Laboratory evaluation of termite resistance of five lesser-known Malaysian hardwoods used for roof and ceiling construction
2001 - IRG/WP 01-10398
The general laboratory procedure of AWPA E1-97 was used to evaluate the termite resistance of 5 lesser- known species (LKT) of Malaysian hardwoods: Kekatong (Cynometra sp.), Kelat (Eugenia spp.), Mempening (Lithocarpus spp.), Perah (Elateriospermum tapos) and Pauh Kijang (Irvingia malayana) against the subterranean termite Coptotermes curvignathus over 28 days. Kempas (Koompassia malaccensis) and ...
A A H Wong, Kee Suan Cheok, J K Grace
Laboratory testing of wood natural durability - In soil-bed assays
1998 - IRG/WP 98-20141
Laboratory methods for assessing wood decay resistance are being investigated in the framework of an ongoing European research project. This paper summarizes the main results obtained for soil-bed tests based on the European prestandard ENV 807-Test 2. The data suggest that this testing methodology is suitable for evaluating the natural durability of timber species in soil-contact under conditions...
R Sierra-Alvarez, I Le Bayon, J K Carey, I Stephan, J Van Acker, M Grinda, G Kleist, H Militz, R-D Peek
Occurrence of termite species on decaying heartwood specimens exposed 18 to 23 years at an Australian site
1998 - IRG/WP 98-10270
The occurrence of species of subterranean termites on hardwood and softwood specimens (including preservative-treated), exposed in-ground at a semi-arid site at Walpeup (north-western Victoria), 18 to 23 years after installation, is reported. This paper presents maps of the cumulative occurrence on specimens, after six annual inspections, of the following species: Coptotermes acinaciformis, Hetero...
J W Creffield, J-D Thornton, G C Johnson
Above-Ground Durability Estimation in Australia. Results after 16 years exposure
2005 - IRG/WP 05-20314
A program of research was established in 1987 to examine the above-ground durability of a selection of timbers that are commercially significant in Australia. Test samples were assembled in an L-Joint design and placed on exposure racks in a format to replicate joinery that is exposed to the weather above ground. Both painted and unpainted material has been exposed.
Test samples have been evaluat...
L P Francis, J Norton
Variation of natural durability of sugi (Cryptomeria japonica) wood in 15 clones examined by decay test (Preliminary report)
2004 - IRG/WP 04-10526
Natural durability of wood in 27 trees from 15 clones of sugi (Cryptomeria japonica)　 was investigated by an accelerated decay test. Thirty years old trees were collected from a clonal trial in Ibaraki prefecture, Japan. Natural durability is usually evaluated in heartwood. Mass losses of heartwood caused by a brown rot decay fungus, Fomitopsis palustris and a white rot decay fungus, Py...
K Yamamoto, A Tamura, R Nakada