IRG Documents Database and Compendium

Search and Download IRG Documents:

Between and , sort by

Displaying your search results

Your search resulted in 282 documents. Displaying 25 entries per page.

Problem of the treatment of dried sawn spruce building timbers with water-borne preservatives. Interim reports for discussion at the 4th Annual Meeting in West Berlin on 27 October 1972
1972 - IRG/WP 311
One of the most difficult technical problems facing the preservation industry is how to improve the treatment of refractory species of timber such as spruce. Its resistance to penetration, even under pressure' precludes its use for more hazardous service situations, and even in less severe conditions a higher level of treatment would be desirable. The importance of this subject led us to look once again at possible ways of improving treatment.
W Liese, J W W Morgan, T Hof, R O Ullevålseter

Treatment of dried sawn spruce and redwood building timbers with water-borne preservatives under a scheme for the quality control of the preservation and preserved wood in the Netherlands
1978 - IRG/WP 3123
Treatment of dried sawn spruce and redwood Building Timbers with water-borne preservatives under a scheme for the quality control of the preservation and preserved wood in the Netherlands. The aim of this article is to give the reader a modest description of the evaluation of fundamental research in wood preservation into a practical application.
H F M Nijman, N Burgers

Study on the treatment of construction timbers by diffusion methods
1983 - IRG/WP 3252
Several species of timber that could be used for constructional purposes have to be pressure impregnated before such use. Pressure impregnation requires expensive equipment, and needs specialized trained operators, etc, which is not possible in most parts of India. Some timbers cannot be pressure impregnated, but can be treated by diffusion. Diffusion treatments could protect these timbers with simple inexpensive apparatus, using local resources and labour. It is our purpose, therefore, to locate such species which are commonly used in India for constructional purposes, and to preserve these by diffusion; to check if the results are satisfactory, and to find a preservative and simple procedure for the treatments of these timbers based on their treatability.
V R Sonti, B Chatterjee

The dip diffusion treatment of tropical building timbers in Papua New Guinea
1972 - IRG/WP 310
In Papua New Guinea a dip diffusion process using a multi salt preservative developed by C.S.I.R.0. has been in commercial use for 8 years. Over 200 million super feet (236,000 m³ ) of timber has been treated during this period and current rate of treatment is 34 million super feet (80,400 m³ ) of timber per year in 70 licenced treatment plants. The process has been found to be simple to apply, convenient to control and has proved very successful in the protection of timber used out of ground contact and protected from the rain. No serious health hazards to process operators or product users have come to light. In common with other countries in the wet tropics P.N.G. is faced with very serious biological deterioration hazards to timber in houses but dip diffusion has overcome the major problems. During the 16 years in which dip diffused timber has been in service in P.N.G. there have been no notable falldowns, the only falldowns reported being in mouldings in which heavy dressing has removed the preservative envelope, but this is a very rare occurrence and cannot be considered of economic importance.
C R Levy, S J Colwell, K A Garbutt

Major insects attacking timber used for building purposes and a practical approach for their control
1990 - IRG/WP 1449
Lignocellulosic materials like wood, bamboos, palmyra palms, reeds, leaves and grasses have been the oldest materials used by human beings. Although with the rapid pace of industrialisation, specially in several western countries, wood began to be replaced with alternative materials like cement, steel etc. yet its use has not vanished even in highly developed countries. Some of the reasons for this are its inherent advantages over other building materials. Wood is a renewable resource, economical in use, easy to work with and process and possesses adequate strength. In addition, it has better thermal, electrical and accoustic insulation properties and can withstand fire resulting in lesser damage to buildings. In developing countries, like India, where resource exploitation has not kept pace with rapid population growth, the use of wood in building construction has dwindled in preference to alternative materials due to certain reasons like:- (i) use of cement, steel, etc. is regarded as a symbol of industrial advancement, (ii) naturally durable species are becoming scarcer and costly and (iii) lack of knowledge amongst consumers, engineers, designers regarding processing techniques, scientific designing of wooden structures, choice of suitable species according to strength etc. The component of wood varies from 10-15 percent of the total building cost (1) Presently it is reported that nearly 3 million cum. is utilised for building construction which is likely to increase in the near future (2) as there is a shortage of the order of 6 million urban and 18 million rural units. At several recent International consultations on the utilisation of wood in buildings, it has been emphasised that wood, as a constructional material, has not been receiving adequate attention in the training programmes of architects and engineers and that there has been a complete neglect of the large technological potential that exists for replacing solid wood by plywood, particle board, wooden board etc. Introduction of proper processing techniques, careful selection of species for the end use, proper grading practices, reduction of presently permitted safety factors through mechanical grading and improved designing and timber engineering, progressive adoption of re-constituted wood products can lead to considerable savings of wood. The ill organised state of sawmilling industry in most of the developing countries restricts investment potential for essential operations - processing, grading, design development etc. Conversion of timber in advance and stocking of graded and processed sizes and prefabricated components is not possible when units operate in a very small scale and in widely scattered locations. Lastly, sufficient education and confidence in the feasibility of timber structures are yet to be developed amongst consumers, engineers, architects and manufacturers. Apart from timber other forest based materials like bamboo, thatch grasses, leaves, reeds etc. for rural housing cannot be ignored specifically in developing countries like India, where bulk of the population lives in villages and uses these materials without processing. While several problems in the introduction of scientific processing of building materials of lignocellulosic origin, including reconstituted wood, arise due to socio-economic factors and organisation of the industry, the need for research to develop simple and economical processing techniques cannot be ignored for any developing country. It may, however, be pointed out that in India there is already enough data base on properties and working stresses of timbers, seasoning and preservation processes, timber engineering designs, use of reconstituted wood etc. Some of these aspects are briefly highlighted here.
V R Sonti, B Chatterjee

Errata in Document NO: IRG/WP/472
1981 - IRG/WP 483
L N Santhakumaran, J C Jain

Microbiological degradation of wooden piles in building foundations
1988 - IRG/WP 1370
White rot, soft rot and bacterial attack have been detected in softwood piles under buildings. In some cases bacteria were found to be the main degradation organisms in the studied piles. The water content of degraded piles was very high. The compression strength was quite low also in the piles deteriorated by bacteria. The density of wood was very variable, and the degree of degradation could not be evaluated according to density analyses.
L Paajanen, H Viitanen

Finishes for outdoor timbers
1975 - IRG/WP 378

Penichroa fasciata (Stephens) (Col. Cerambycidae) a pest in wood materials
1988 - IRG/WP 1365
Penichroa fasciata (Stephens) (Col. Cerambycidae) is found to be a frequent pest occurring in hardwood in storage in Italy. This paper reports the characteristic for identification, biological features, distribution and timber liable to attack.
A Gambetta, E Orlandi.

The restricted distribution of Serpula lacrymans in Australian buildings
1989 - IRG/WP 1382
Temperature data has been gathered over a number of years, not only for flooring regions of various buildings in Melbourne, but also within roof spaces and external to the buildings. Findings are discussed in relation to the distribution of Serpula lacrymans within Australia, its restriction to certain types of building construction and its restriction to flooring regions. The subfloor spaces of badly-ventilated, masonry buildings are highlighted as being better suited than are the subfloor spaces of, for example, Japanese buildings for the activity of this fungus. Hence Serpula lacrymans is very restricted in its distribution in Australia, yet where it is active it does grow rapidly and causes rapid flooring failures.
J D Thornton

An evaluation method for less termite attack execution on thermal insulation for fundation walls
2002 - IRG/WP 02-20245
According to the results by the real scale Japanese building tests, the termite installation was observed at very little spaces between foundation and insulation. The termite penetration spaces between foundation and insulation on foundation systems in Japanese wooden houses were checked by the way of streaming speed of colored water. Because of difficulty for its execution, the parts of outside angles and reentrant angles in continuous foundation were more sensitive for the termite penetration. Special accessories of thermal insulation for these angles can be effective for lesser termite installation.
K Suzuki, Y Tanaka

Fungal and bacterial attack of CCA-treated Pinus radiata timbers from a water-cooling tower
1991 - IRG/WP 1488
Transmission electron microscopy of decaying CCA-treated Pinus radiata timbers from an industrial water cooling tower showed presence of a thick biofilm covering some areas of the wood. The biofilm contained various morphologically distinct forms of microorganisms embedded in a slime. The study provided evidence of the activity of soft rot fungi and tunnelling and erosion bacteria in wood cells. The extent of damage to wood cells due to microbial activity varied, combined fungal and bacterial attack having the most damaging impact.
A P Singh, M E Hedley, D R Page, C S Han, K Atisongkroh

Comité International Permanent pour la Recherche sur la Préservation des Matériaux en Milieu Marin. Information from the Wood Group
1980 - IRG/WP 460
E G B Jones

Report on the monographic card on Coniophora puteana
1973 - IRG/WP 114
A Käärik

Monographic information on Lentinus lepideus.markup
1973 - IRG/WP 121
G Seehann, W Liese

The susceptibility of 35 Amazon wood species to Cryptotermes brevis (Walker)
1982 - IRG/WP 1160
Laboratory tests were carried to evaluate the susceptibility of 35 Amazon hardwoods to Cryptotermes brevis (Walker). The results were analysed statistically and showed that five wood species were non resistant, nine were resistant and the other twenty-one in between those classes of resistance.
M D Canedo

Some observations on Chlorophora pilosus Forst. var. glabromaculatus Goeze (Coleoptera, Cerambycidae)
1980 - IRG/WP 1119
A Gambetta

Recent soft-rot research in softwoods and hardwoods
1980 - IRG/WP 1108
The purpose of this paper is to describe briefly the current status of our research on soft-rot fungi. The work to be discussed is still in progress and any results described must be regarded as provisional.
J A Butcher

Natural durability transfer from sawmill residues of white cypress (Callitris glaucophylla). - Part 3: Full penetration of the refractory sapwood of white cypress
2000 - IRG/WP 00-40167
The heartwood of white cypress, Callitris glaucophylla, is renowned for its termite resistance and durability against decay. The sapwood, which can represent up to 30% of log volume, is non-durable and refractory to conventional preservative treatment. Previous work ascribes the lack of permeability to oily deposits within tracheids and ray cells. Environmental scanning electron microscopy was used to investigate ultrastructural aspects of sapwood permeability. Several pre-treatment processes to improve permeability were tested with limited success. Solvent drying allowed preservative penetration but damaged the structure of the timber. Neither, long term water soaking nor an oscillating pressure/vacuum cycle had any effect on porosity to water-borne treatments. Through extensive modifications to a standard VPI process we can now repeatedly achieve full penetration with organic solvent-based wood preservative solutions into white cypress sapwood. Effects of this process on the strength of the timber are being evaluated. Work is continuing as to the most effective and efficient treatment schedule and the latest results will be presented at IRG 31.
M J Kennedy, L M Stephens, M A Powell

The biostatic effect of copper on decay of fire retardant-treated mining timber
1991 - IRG/WP 1507
Blocks of Eucalyptus grandis were treated with 20kg/m³ ammonium sulphate as fire retardant and challenged with Coriolus versicolor. Replicates were soil buried. A second set of blocks was treated with retardant and copper at 6.6 kg/m³ (ie 1% w/w), and challenged similarly. After 8 weeks weight losses produced by Coriolus versicolor in untreated, retardant treated and copper supplemented blocks were 45, 25, and 0% respectively, and corresponding weight losses in soil were 27, 25 and 10%. These results, and electronmicroscopical observations, showed conclusively that Eucalyptus grandis treated with fire retardant was rapidly decayed, and that copper inhibited such decay.
G D Shelver, E A Shelver, A A W Baecker

Feeding preference behaviour of Crytopermes cynocephalus Light and Coptotermes curvignathus Holmgren on twenty-eight tropical timbers
1985 - IRG/WP 1251
A study on the feeding preference behaviour of a dry-wood termite Cryptotermes cynocephalus Light and a subterranean termite Coptotermes curvignathus Holmgren on 28 species of tropical timbers has been conducted. The weight-loss of individual timber and the mortality of termite was·recorded after 5, 10, 15, 20 and 25 days of exposure. The results reveal that there are only five species among 28 species of wood which are completely repellent to both the dry-wood termite Cryptotermes cynocephalus and the subterranean termite Coptotermes curvignathus. These five wood species are Dalbergia latifolia, Eusideroxylon zwageri, Intsia bijuga, Lagerstromia speciosa and Tectona grandis. There are eight wood species which are repellent to Cryptotermes cynocephalus and seven wood species which are repellent to Coptotermes curvignathus. There are also only seven wood species which are completely arrestant or highly arrestant to both species of termite. Agathis alba and Mangifera indica are classified as highly arrestant to both the dry-wood and the subterranean termites. Other species are classified between moderately repellent to highly arrestant.
Nana Supriana

Data sheet on woodboring insects. 1. Bostrychus capucinus (Linnaeus)
1979 - IRG/WP 193
S Cymorek

Monographic card for Stereum hirsutum
1973 - IRG/WP 119 E
C Jacquiot

Natural Resistance of timbers to marine borer attack. COIPM/IRG CO-OPERATION. Final report concerning panels exposed in the sea at Sekondi, Ghana
1979 - IRG/WP 449
The test was carried out according to Document COIPM/72.044, Revised procedure for the testing of naturally durable timbers against marine borers. The panels of the three species remaining in the test at the end of 1978 were removed and assessed visually. An average rating was given to the panels of each species.
F F K Ampong

Long-term effectiveness of fumigants in controlling decay in Douglas fir waterfront timbers
1986 - IRG/WP 3364
The persistence, movement, and effectiveness of chloropicrin and Vapam (sodium N-methyl dithiocarbamate) in large, horizontal Douglas fir timbers were evaluated 7 years after fumigation. Chloropicrin prevented reestablishment of decay fungi; reinvasion occurred in some Vapam-treated timbers. Residual fungistatic effect was detected up to 1.2 m from the fumigation site in chloropicrintreated timbers but not in Vapam-treated timbers.
T L Highley

Next Page