Your search resulted in 486 documents. Displaying 25 entries per page.
A study on insect pests and preservation of fire-damaged timbers in Da Xing An Ling forest region
1991 - IRG/WP 1499
Investigated insect pest of timbers of Da Xing An Ling forest region by means of sampling inspection. Meanwhile we had researched insects pest situation, regularity occurred and biological nature for fire damaged timbers attacked in the log yard. The results showed that the mainly insect species are small black-marmorated longicorn (Monochamus sutor L). We had eagaged in various small tests of timber preservation such as: underwater storage, brushing, spraying and fumigation. The results showed that the fumigant treatment was successful. By means of medium-sized tests of fumigant treatment many times. We had obtained the ideal fumigant and the amount of treatment as well as period of treatment.
Lu Wenda, Li Jian, Shao Jing Wen, Liu Yixing, Cui Yongzhi
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
Non-destructive evaluation of termite and decay damaged to timber-in- service
2010 - IRG/WP 10-20451
A leading joint research project was financed by the ARC, engaging some of the leading Universities in Australia, to look at field techniques to determine if timber-in-service is infested with termites and decay fungi after which microwave technology will be employed to eliminate the termites and/or decay in-situ. The next step will be to quantify the damage caused on the sectional dimensions of the pole to enable us to make a decision about whether to replace or repair the timber-in-service under investigation. The purpose of this paper is to explore the development of non-destructive detecting for quantifying any damage caused by the termite and/or decay attacks. Some preliminary tests were conducted and a literature review was conducted on existing methods of non-destructive evaluation to explore new methods and evaluate the degree of damage that termites and decay cause to timber-in-service and its structure.
C Adam, B M Ahmed Shiday, G Brodie
Laboratory investigation of fire protection coatings for creosote-treated timber railroad bridges
2014 - IRG/WP 14-30639
As the incidence of timber railroad bridge fires increases, so has the need to develop protective measures to reduce the risk from accidental ignitions primarily caused by hot metal objects. Of the six barrier treatments evaluated in the laboratory for their ability to protect timbers from fires sourced with ignition from hot metal objects only one intumescent coating provided adequate fire protection. The intumescent barrier treatment also met environmental, performance (e.g. bond durability) and application criteria set forth in this study. These criteria also dictated the development of a flammability test, called the hot metal test that is compatible with the fire scenario specific to this study. The hot metal test evaluates protective materials on creosote-treated timber against ignition of gases generated by an 1100ᴼC heat source.
C A Clausen, R H White, J P Wacker, S T Lebow, M A Dietenberger, S L Zelinka, N M Stark
Self-Extinguishment Phenomena of Mass Timber in Medium-Scale Compartment Fires
2018 - IRG/WP 18-30729
This paper presents a review of the fire safety risks that mass timber construction may introduce in buildings, with special consideration to medium- and high-rise buildings. These main risks are represented by an effect to the classical fire safety strategy for buildings: (1) Compartmentalisation, to ensure that the fire will not spread farther than the compartment of origin, (2) Preventing vertical flame spread to avoid façade and multi-floor fires. These requirements are essential if an adequate fire strategy has to be achieved. In order to study these newly identified risks in buildings with exposed mass timber (i.e. Cross-Laminated Timber); five medium-scale compartment fire tests were conducted of internal dimensions 0.48 m x 0.48 m x 0.37 m. Two tests had one sidewall and the ceiling of exposed CLT, while the other three were baseline tests (i.e. same geometry and the CLT completely encapsulated). Results consisting of incident radiant heat fluxes onto the compartment walls and the façade area above the window are presented herein. These are the parameters that will determine if self-extinguishment and vertical flame spread will occur. Self-extinguishment of the exposed timber occurred for all the tests with exposed mass timber after the fire consumed all the available fuel on the floor of the compartment. Therefore, after burnout, the heat flux onto the exposed walls was below the critical heat flux for self-extinction. Nevertheless, it was difficult to compare the heat flux data at the time of self-extinguishment with previous outcomes for self-extinguishment conducted on bench-scale testing, as the time scale differences induce a considerable delay before flameout is observed. The heat fluxes into the façade were as much as two times bigger when exposed timber was present.
C Gorska, J P Hidalgo
Thermal performance and fire safety properties of traditional circumferential log-cabin walls
2019 - IRG/WP 19-40872
The paper describes the experiment of fire resistance of a circumferential log-cabin wall fragment using various structural modification of the gap between two log members. The influence of the gap structural modification on the criterion of fire resistance E (envelop integrity) and I (insulation) is evaluated. The evaluating criteria are represented by the development of temperatures measured in various gap setups and photo documentation from the experiment. The experiment is supplemented by the theoretical calculation of the temperatures during a fire on the unexposed fragment side in two cases: according to the average temperatures on the specimen surface from the radiation panel and for the standardised fire temperature 1,000°C. The reason for the calculation is the verification of the I criterion (insulation) in connection with the U-value of the construction, i.e. heat transfer affecting the flashpoint temperature on the unexposed side of the log-cabin wall.
S Jochim, L Makovicka Osvaldova, M Zachar, Z Danihelova
A Comparison of Cross-Laminated Timber (CLT) Floor Panels using Finite Element Analysis and Experimental Fire Testing
2022 - IRG/WP 22-40955
Cross-laminated timber (CLT) is a relatively new timber product and has gained popularity in North America and Europe as a construction material. As a sustainable engineered timber product, CLT offers many advantages over solid wood, concrete, or steel construction. However, the use of timber in medium to high rise buildings is often avoided mainly due to its combustible nature. In this paper, a numerical model of a CLT floor panel was developed using the Finite Element (FE) Method in Abaqus. This paper analyses the thermal behaviour of a CLT panel when exposed to a standard test fire. In the modelling of a CLT floor panel, Eurocode 5 temperature-dependent relationships were adopted. The results of the FE model were then compared with the experimental tests performed for a similar-sized panel. The charring rate and temperature distribution across the depth of the CLT panel were investigated for all test specimens and comparisons were made with the experimental results. The comparisons of FE results with experimental results showed that the FE analysis gave reasonably accurate results to allow for the development of full-scale computational models of a prototype CLT building.
M Yasir, A Macilwraith, K Ruane
Solvent drying and preservation of timber
1977 - IRG/WP 381
Processes which combine drying and preservation are first reviewed. Some preliminary experiments are then described in which blocks of green Sitka spruce sapwood were immersed, in a solution of tributyltin oxide (TBTO) in methanol at 60°C. Satisfactory penetration of the preservative and exchange of methanol and water occurred in a few hours. The methanol was removed rapidly from the wood by evaporation. Satisfactory penetration of TBTO into initially methanol-saturated samples occurred in a similar period. The factors influencing. such treatments are discussed. High initial moisture content of the wood and a high operating temperature are particularly desirable. Some aspects of the possible commercial operation of the process are discussed.
J A Petty
Screening potential preservatives against stain and mould fungi on pine timber in Zimbabwe
1995 - IRG/WP 95-30063
The search for environmentally and toxicologically safer chemicals for use in the timber preservative industry against stain and mould fungi has been intensified during the past few years. Results of field tests with two chemicals previously evaluated in the laboratory are presented. The conventional sodium pentachlorophenate was the more efficacious chemical against stain and mould fungi, providing up 90% control at a concentration of 2.5%. A potential alternative, Stopstain a borate-based chemical, gave results only slightly better than the untreated control timber, at a concentration of 5%. Unless the environmental cost and toxicological hazards of traditional chemicals are highlighted the newer and safer chemicals will be reluctantly accepted by industry as they are regarded as being prohibitively expensive.
A J Masuka
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 2: Report of treatment and installation in Australia
1978 - IRG/WP 440
The purpose of this test and the procedures to be followed have been fully set out in documents distributed by the International Research Group on Wood Preservation and numbered IRG/WP/414 and IRG/WP/420. The prescriptions set out in these two documents have been closely followed.
Manual of a mini treating plant for waterborne preservative treatment of timber and bamboo
1999 - IRG/WP 99-40130
This contributional article includes machinaries and equipments necessary for a small wood treating plant for the pressure treatment of tim bers with waterborne preservatives along with the cost and design. The preservative treatment limitations, treatment schedules and specifications for different products have been described. The cost of a mini treating plant will be 6,00,000 Tk. (13,000 US$), suitable for preserving timber and bamboo products for indoor and outdoor uses and will out last teak wood. The additional durability of timber and bamboo will create economically and environmentally safe conditions.
A K Lahiry
Field performance of wood preservative systems in secondary timber species
1997 - IRG/WP 97-30152
The objective of this ongoing study is to evaluate the performance of new, potential, and standard wood preservative systems in secondary North American timber species. Eleven preservative systems were evaluated in this study - ACQ Type B, Copper Citrate 2: l, CDDC, chlorothalonil/chlorpyrifos, copper-8-quinolinolate, tebuconazole/chlorpyrifos, RH287, propiconazole/chlorpyrifos, copper naphthenate, CCA. and creosote. Field evaluations are being performed with ground contact field stakes and termite-specific testing in Hawaii, along with laboratory soil bed tests. The major wood species used with all the systems and evaluation methodologies are loblolly pine, northern red oak, tulip poplar, and cottonwood. More limited evaluations (field stakes only) are being conducted with eastern hemlock, red maple, and sweetgum. Information is presented from laboratory soil bed, field termite, and field stake evaluations. There is good correspondence between soil bed and field stake results. The more highly developed preservative systems and those in an AWPA P9 Type A oil carrier tend to perform better, and there can be a strong affect on performance from the wood species.
P E Laks, K W Gutting, R C De Groot
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. 2nd Interim Report
1981 - IRG/WP 477
Three reference wood species - Alstonia scholaris, Fagus sylvatica and Pinus sylvestris, untreated and treated with 3%, 6% and 10% CCA and CCB solutions were supplied to all participants for submergence at local sites. Regular examination of samples is being carried out - 6 months, 12 months and then annually for 7 years.
R A Eaton
Report an some aspects of forest and the timber preservation in Fiji 1999
2000 - IRG/WP 00-40189
This report is divided in two sections. One is the general description of some aspects of the Forest indicating timber availability in Fiji. The other Section is an "Status of Timber Preservation in Fiji in 1999".
S D Kumar
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 10 from Naos Island, Panama
1980 - IRG/WP 462
Blocks of 3 wood species, Beech (Fagus sylvatica), Scots pine (Pinus sylvestris) and Alstonia (Alstonia scholaris) were exposed at site number 12 at Naos Island, Panama on March 8, 1978 by John R. DePalma. The arrangement of the panels in the exposure site is as shown in Figure 1.
D W French
Fire resistance of preservative treated fence posts
1994 - IRG/WP 94-30033
Pine fence posts were pressure treated separately with CCA-C, CCA-wax, CCA-oil and creosote. Treated posts and untreated controls were planted in the ground in a randomised block design, weathered for six months and then subjected to a controlled burning test using two fuel loads. Creosote treatment increased the time that posts were alight whereas CCA treatment had no such effect. However, CCA treated posts smouldered until destruction of the majority of the posts occurred. Posts treated with CCA-oil took longer for destruction to occur than posts treated with CCA-C or CCA-wax. Creosote treated posts and untreated controls did not show prolonged smouldering and consequently were not destroyed by the burning test, although their strength was reduced. A high fuel load increased the time that posts were alight and smouldering, and for CCA treated posts decreased their time to destruction.
P D Evans, P J Beutel, C F Donnelly, R B Cunningham
Electrodialytic remediation of creosote and CCA treated timber wastes
2002 - IRG/WP 02-50190
There is a growing concern about the environmental issue of impregnated timber waste management, since an increase in the amount of waste of treated wood is expected over the next decades. Presently, no well-documented treatment technique is yet available for this type of waste. Alternative options concerning the disposal of treated wood are becoming more attractive to study, especially the ones that may promote its re-use. Inside this approach, the electrodialytic process (ED) seems a promising technique for removal of preservative chemicals from treated wood waste. The method uses a direct electric current and its effects in the matrix as the “cleaning agent”, combining the electrokinetic movement (mainly due to electromigration, but also electro-osmosis and electrophoresis), with the principle of electrodialysis. This work reports results from the application of the electrodialytic process to an out-of-service Portuguese creosote and CCA-treated Pinus pinaster Ait. railway sleeper and pole. The behaviour of the process is described and the main results discussed. The average removal rate, estimated in accordance with prEN 12490, for creosote from treated timber waste was around 40 %.. For CCA treated timber waste, experimental conditions that could optimise the process efficiency (e.g. current density, time) were studied. The highest removal rates obtained until now, in our studies, were 93 % of Cu, 95 % of Cr and 99 % of As for sawdust using 2.5 % oxalic acid (w/w) as the assisting agent. For CCA treated wood waste in the form of chips, the best removal rates obtained until now were 84 % of Cu, 91 % of Cr and 97 % of As.
E P Mateus, A B Ribeiro, L Ottosen
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 13: Report of fourth inspection (36 months) in Australia
1981 - IRG/WP 481
This report presents the results of the fourth inspection of the IRG/COIPM International Marine Test specimens installed in Sydney Harbour in December, 1977. The inspection took place on 9th December, 1980, after 36 months exposure. Full details of the treatment and installation of the specimens, as well as results of the first three inspections (after 6, 12, and 24 months exposure), have been presented in earlier reports. All inspections of this test have been carried out in accordance with the Working Plan (see IRG/WP/414) except for an X-ray examination of the specimens. This facility is not available at the test station. In conformity with the provisions of the Working Plan, the fifth and sixth replicates of the whole test (i.e. those specimens with '5' or '6' as the final digit of their serial number) were recovered and returned to the United Kingdom after 6 months and 24 months of immersion. Thus, only four replicates remain to be examined at this and ensuing inspections.
An investigation of the effects of pre-steaming on the treatment of sawn spruce timber with Celcure A, a copper-chrome-arsenic preservative
1981 - IRG/WP 3150
Difficulties in the treatment of spruce using standard vacuum/pressure techniques with both water-borne and organic solvent preservatives are well known. We have evaluated the influence of steaming on treatability with a waterborne CCA preservative.
C R Coggins
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 8: Panama test results
1980 - IRG/WP 458
Summary of damage to ITRG test stakes by pholadidae and teredinidae at the Panama test site - 8 Mar. '78 to 11 Oct. '79
J R De Palma
Boron treatments for the preservation of wood - A review of efficacy data for fungi and termites
1994 - IRG/WP 94-30037
Boron treatments have been used for many decades for protection of timber from biological attack and also as a fire retardant treatment. In recent years there has been an increased interest in boron treatments as an option for protection of structural timbers' e.g. timber framing used in termite risk areas. This paper reviews efficacy data for both fungi and termites relevant to this end-use.
J A Drysdale
Observations on the colonization of freshly-felled timber treated with prophylactic chemicals by mould and sapstain fungi
1989 - IRG/WP 1394
Field tests using freshly felled pine sapwood were set up to determine the effectiveness of a range of antisapstain compounds and to study the problems of colonization by mould and sapstain fungi. Differences were recorded both in the overall performance of the compounds and also their selectivity in controlling specific fungal types. These results were found to be useful in gaining a better understanding of biocide - fungal interactions.
G R Williams, D A Lewis
Conforming to european standards for preservative-treated timber: Specifying with confidence
2000 - IRG/WP 00-20194
A four-year collaborative study between four industrial partners and BRE has assessed timber treated by current UK industrial practices in the light of current European Standards. Data were collected for CCA and creosote treated timber components, and compared with the requirements laid out in EN351-1 and -2. A number of difficulties were encountered that have been described in previous IRG papers (98-20150, 99-20156), such as the poor reproducibility of chemical analyses and variable timber density. This paper describes the conclusions of our collaboration, focusing on the application of the findings and how to overcome any difficulties encountered. The data collected allowed the calculation of figures that have been submitted for inclusion into the UK's proposed national code for preservative-treated timber (DD239). An example is the recommendation of new minimum retention figures for creosote-treated commodities. This paper describes the factors that will enable UK specifiers to use the European Standards with confidence and greater understanding of how they map onto traditional methods of specification. In addition valuable lessons have been learnt applicable to the industry world wide.
E D Suttie, R J Orsler
On site test for indicative determination of leaching of components of preservatives from treated timber. Part 2: New data on CCA-C, CC and CCB treated timber
1994 - IRG/WP 94-50025
The 'on site test' was published at the IRG meeting in Cannes in February 1993 (IRG/WP 93-50001/12). Since this publication many on site tests were performed parallel to so-called shower tests. The correlation between the test results of the on site tests and the shower test has been established more clearly. For chromium the correlation between both tests is indistinctive of preservative formulation. For copper the correlation differs for CCA on one side and CC's and CCB's on the other side. In some cases the on site test does not correcty predict shower test results. The reasons for this phenomenon are discussed. It can be concluded that the on site test is a roughly indicative test for assessing the leaching of components of preservatives from treated timber. The correlation figures, however, are formulation dependent.
W J Homan
Recycling of pressure impregnated timber and preservatives - incineration techniques
2001 - IRG/WP 01-50166-19
The object of the recycling research projects is to determine the technical and economical requirements of the recycling of CCA-impregnated wood. In the first recycling of impregnated timber project the amount and location of recyclable treated wood in Finland was determined and the costs of recycling were calculated. An incineration test was also made (1998). The conclusion of the first project is that it is possible to design a full scale plant for burning CCA-treated wood, to treat condensate water, to purify the gases using a very effective method, and to treat the ash in a copper smelter. The object of the second recycling research project in Finland is to determine the technical and economical requirements of incinerating CCA-impregnated timber so that an investment decision can be taken on whether to build an incineration plant. Thus far in the course of the second project a trial has been established for collecting impregnated sawn timber at waste treatment plants and for cleaning the material of large metal constituents. The first part of the incineration trial was carried out in November 2000 and this will continue in the spring of 2001, after which an interested investor can reach a decision on a possible investment.
T Syrjänen, E Kangas