Your search resulted in 221 documents. Displaying 25 entries per page.
The practice of using concrete on wood piling for marine use in Thailand
1982 - IRG/WP 492
The practice of using concrete on wooden poles has been carried on in Thailand for a long time in pile-houses and pier constructions which have been situated in, or partly in the sea. In such instances, the hewed round and/or square-sawn heartwood poles of naturally durable timber species have been coated with concrete of about 5 to 10 cm or more in thickness, and to about 100 cm above the highest...
B Anuwongse
Discoloration of pressure impregnated wood caused by Amorphotheca resinae
1990 - IRG/WP 1438
Amorphotheca resinae Parbery with the anamorph Cladosporium resinae (Lindau) von Arx & de Vries is a cosmopolitan fungus known from aviation kerosene, hydrocarbon contaminated soil and creosoted timbers. In Denmark it causes heavy discoloration on wood treated with waterborne chromate-containing preservatives e.g. CCA-oxide type. The teleomorph produces small spherical fruitbodies widespread o...
F Rune, A P Koch
The field performance of CCA-C treated sawn refractory softwoods from North America
1997 - IRG/WP 97-40085
Approximately 15% of the total volume of wood treated in the United States consists of difficult to treat softwoods known as "refractory softwoods". The long term positive performance record of CCA treated sawn material is based upon the testing of yellow pine sapwood stakes with only limited field data available for sawn refractory softwoods. As a result, the existing North American wood preserva...
M J Richards, W S McNamara
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
Lignicolous marine fungi from panels of different timbers exposed along Goa coast (India)
1993 - IRG/WP 93-10037
Colonisation by marine fungi on panels of thirty species of Indian timbers, ten species of imported timbers, marine plywood (coated with polyurethane as well as uncoated) and also on panels of five timber species treated with Copper-Chrome-Arsenic (CCA) and Copper-Chrome-Boric (CCB) preservatives, was studied by exposing test blocks in the Mandovi estuary, Goa (West coast of India) for periods ran...
L N Santhakumaran, S Chinnaraj, S G Sawant
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
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
Influence of clonal variability on the impregnability of poplar hybrids. (+ correction document of 23 April 1990)
1990 - IRG/WP 3614
The new Western European poplar clones (Populus nigra x deltoides and Populus trichocarpa x deltoides) were compared with the reference clone 'Robusta' and some old hybrids. Samples (5x5x50 cm³) with pure tangential/radial surfaces were sawn, including the transition zone between heartwood and sapwood. Treatment by a standard vacuum-pressure impregnation cycle with CCA showed a ...
J Van Acker Van, M Stevens, C De Haas
Soft rot
1978 - IRG/WP 179
Soft rot decay of treated wood is examined with special reference to hardwoods treated with CCA. Factors which adversely affect the chances of protection of hardwoods against soft rot are discussed. The ratio of the volume of the fibre cell wall to the volume of the fibre lumen is presented as a major factor influencing final preservative concentration in the fibre cell wall, the major strength co...
C R Levy
Fungi causing sap stain in wood
1980 - IRG/WP 199
The present paper is a revised edition of former Document No: IRG/WP/125. It contains some additions and an explanation of terminology, as was suggested at a previous meeting of the Group. The paper is a compilation based mainly on available literature. Some of my own unpublished results have been added together with other unpublished data which have been received from the Bundesanstalt für Mater...
A Käärik
Venezuelan net of test fields for the study of the effectiveness of treatments of non commercial timbers from natural tropical forests
2005 - IRG/WP 05-20318
A net of 13 tests fields were established in Venezuela for the study of the effectiveness of the CCA and CCB treatment in secondary or non commercial woods from natural forests, two woods from fast growth plantations wee included for promote them as treated timber mainly for fence posts uses. Partial results after two years are presented and discussed the preliminary results obtained both in field...
O Encinas, N Mora
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
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
Bacteria are important degraders of cooling tower timbers: New Zealand experience
1995 - IRG/WP 95-10128
Microscopic examinations of CCA-treated Pinus radiata timbers in industrial cooling towers in New Zealand showed bacteria and soft rot fungi to be primarily responsible for the decay of these timbers. Of these micro-organisms, erosion bacteria appeared to be most widespread, attacking wood cell walls independently as well as together with tunnelling bacteria and soft rot fungi. Tunnelling bacteria...
A P Singh, R N Wakeling
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
Wharf-borer a threat to stored archaeological timbers
1992 - IRG/WP 92-1560
Increased interest in marine archaeology has occured in recent years. Stored waterlogged archaeological timbers have been shown to be degraded by physical and microbial agents. In recent years a new threat has been highlighted, namely the wharf-borer Nacerdes melanura (L.). The objective of this paper is to outline studies of the morphology, biology, life-history and carbohydrate digestion by this...
A J Pitman, E B G Jones, A M Jones, M Rule
A review of incising as a means of improving treatment of sawnwood
1994 - IRG/WP 94-40019
The use of incising, perforation of the wood surface, is increased because of the need to treat refractory wood species. This paper reviews the development of incising and shows how the required incising patterns can be determined and specified. Most of the development has been in the area of toothed-roller incisors because of their rapid throughput. Needle, Laser, drill and water jet incisors hav...
P I Morris, J J Morrell, J N R Ruddick
Permanence of permethrin and bifenthrin in framing timbers subjected to hazard class 3 exposure
2005 - IRG/WP 05-30383
End-sealed Pinus radiata specimens measuring 235 x 90 x 35 mm were treated using a modified Lowry schedule with permethrin or bifenthrin in white spirit to Hazard Class 2 (H2) retentions. After conditioning, the specimens were exposed at 45o on north facing racks near Melbourne (Australia). Samples of the specimens were taken before installation, and after three and six months exposure. Analyses o...
A C Hunt, D G Humphrey, R Wearne, L J Cookson
Assessment of untreated Papua New Guinea timbers against subterranean termites. Final report
1993 - IRG/WP 93-10041
Four years after the exposure of eight timber species of varying density against subterranean termites in a field trial, Kwila was still generally sound while Taun, Malas and PNG Walnut were beginning to be attacked slightly to moderately. Calophyllum, Kamarere, PNG Beech and White Cheesewood were severely attacked and failed. Results after the period of exposure shows that Kwila rates highly as t...
H C Konabe, M Rokova
Laboratory tests on the natural durability of timber methods and problems
1984 - IRG/WP 2217
In literature a large variety of test methods is mentioned to examine the natural resistance of timber against fungal attack. This concerns the kind of sampling as well as the test procedure, the test fungi, the duration of test, and the classification of the resistance according to the test results. These variations, however, are of great influence on the test result. Long term exposure will lead...
H Willeitner
Alternative timbers to Iroko (Milicia excelsa) for various end-uses: Ghana’s offer
2004 - IRG/WP 04-10518
There are hundreds of timber species indigenous to Ghana and several exotic species have been
extensively planted. The timber industry in Ghana is very important to the country’s economy. Despite
its small size relative to the world trade in timber products, it has the potential to be a driving force in the development of the Ghanaian economy. The industry is currently going through a period...
S A Amartey, Zeen Huang, A Attah
Methods of culturing Lyctidae
1980 - IRG/WP 1126
Members of the tropical countries in the IRG Sub-Group "Insects in dry wood" requested a paper on the breeding of lyctids. Compared with other wood boring insects, such as cerambycids and anobiids, the breeding of lyctids is not as difficult and time consuming. Nevertheless some basic principles have to be observed in the laboratory to obtain successful cu·ltures. It is the intention of this repo...
H Kühne
Comparative natural resistance of eighty-two timber species to damage by marine borers at Goa (India)
1996 - IRG/WP 96-10139
Natural bioresistance of eighty-two species of Indian timbers to attack by marine wood-borers has been presented based on data collected from test panels exposed in Goa waters (west coast of India) for periods ranging from five to thirteen months. All the timber species, except Artocarpus gomeziana and Pterocarpus santalinus, were completely destroyed within a short period of three to six months. ...
L N Santhakumaran
Observations on preservative penetration in poplar
1991 - IRG/WP 3662
In the course of studies on the CCA treatment and durability of poplar timber a zone of refractory wood at the sapwood/heartwood boundary was observed. Further studies were conducted to investigate the causes of this refractory behaviour. The initial results have suggested that the presence of lipid storage products in the ray tissue may lead to impermeability, either by directly blocking pits or ...
R J Murphy, S U Din, M J Stone
Role of wood preservation in bioconservation and protection of environment
1997 - IRG/WP 97-50082
In order to meet a revolutionary task of bioconservation and protection of environment through preservation of less important and nondurable timbers from tropical zones, 170 timber species from Bangladesh were screened. Air-dried (12% MC) 170 different species of timbers, full cell pressure impregnated with 5% CCB solution revealed satisfactory treatability of all timbers for long-term indoor uses...
A K Lahiry