Your search resulted in 68 documents. Displaying 25 entries per page.
A Long-term Observation of Termite Activity in The Nest by Continuous Acoustic Emission (AE) Monitoring
2003 - IRG/WP 03-20280
In order to evaluate the influence of temperature on the termite activity, acoustic emission (AE) monitoring was applied to two nests of Coptotermes formosanus SHIRAKI; a nest in the stem of a standing tree and a nest in the underground of a wooden house, respectively. Temperature change in and around the nests were continuously measured for about one year using thermocouples at four points; the centre of the nest, the periphery of the nest, the environment around the nest, and the underground, respectively. AEs were detected at the centre of nest and underneath the nest sphere by using wave-guides inserted into the nest of the standing tree and at the centre of nest. AEs were also detected at the wooden construction member near the nest in the wooden house. The termites in the nests were periodically stimulated by rotating, drawing and sticking the wave-guides. The temperatures in the both nests varied from 5 to 35 °C during the experiment. The highest and the lowest temperatures were recorded in August and February, respectively. The highest AEs event rate was recorded when the temperature of the nest in the tree was between 30 and 35 °C and when the temperature of the nest under the house was above 25 °C. In winter, when the nest temperature was below 10 °C, no significant numbers of AE were detected. These findings clearly show that AE generation has a close relation to the termite activities, which are influenced by the temperature in the nest.
Y Yanase, Y Fujii, S Okumura, T Yoshimura, Y Imamura
Longterm monitoring of termite activity on multiple feeding sites: a laboratory method intended for the determination of attractant/repellent properties of wood preservatives and baits
2001 - IRG/WP 01-20225
A method is introduced allowing the continuous monitoring of the activity of a small laboratory termite- colony at 8 different feeding sites simultaneously. The test assembly consists of a small central polycarbonate-tube containing a colonie of Reticulitermes santonensis (de Feytaud) beeing connected with 8 external feeding sites by small glass-capillaries. The termites passing through the glass capillaries to and from the feeding sites are interrupting an infrared light-barrier. Each signal from the light-barriers is conditioned and fed to a PC-based signal-recognition-, monitoring- and storage-system. First results show that a colony of 500 individuals of Reticulitermes santonensis (de Feytaud) will need approx. 2 to 3 weeks for establishing a new, full functional hierarchy. A well established Reticulitermes- colony will show 80 to 100 passings per minute to and from the eight feeding sites. The activity of Reticulitermes santonensis (de Feytaud) shows no circadian activity rhythmic.
M Pallaske, E Graf, H Takiuchi
Evaluating the Process of ACQ-Treated Woods with TGAand CEM Analysis
2007 - IRG/WP 07-20374
To provide an understanding of the fundamental thermal behaviour and the disposal-end products of ACQ-treated woods, this study is comprised of two categories of examination. The first is related to the use of TGA under different thermal decomposition conditions (nitrogen or air, and 5 or 40 oC/min), and the use of EDX to examine certain residual elements of the char. The second applies the CEM techniques to evaluate the emission gas concentrations of O2 and CO2 concentration, the emission content (CO, SO2, NOx), and the emission gases temperature were measured using a Flue-gas Analyzer from the exit of a 45° flammability testing cabinet as specified in the continuous emission monitoring. The results of the TGA showed that the char of ACQ-treated woods at air atmosphere were less than that at nitrogen, and the pyrolysis temperature for the heating rate of 5 oC/min was lower than that of 40 oC/min, but both them were with the same amount of char. The results of the EDX analysis of ACQ-treated woods obtained that the main element is C (77.89 %), and that the relative proportion of Cu was 2.67 %. The results of CEM indicated that the emission gas temperature of ACQ-treated woods rise rapidly up to about 250 oC and then slowed down in the temperature range of 200 oC shown as a Plateau curve. The concentration of O2 decreased from 20.7 % to about 17 % linearly, and on the contrary the concentration of CO2 increased from 0.2 % to about 2.5%. Both O2 and CO2 then approached the shape of a Plateau curve until the end of the combustion time, as well as had a close relationship during combustion. For the maximum value of the emission content during the combustion, the emission quantity of CO was about 160 ppm. The SO2 emitted gas was zero. The peak for NOx gas was 25 ppm.
Han Chien Lin, Tsang-Chyi Shiah, Jung Ting Tsai
Improvements of monitoring the effects of soil organisms on wood in fungal cellar tests
1996 - IRG/WP 96-20093
Accelerated testing the durability of preservative treated timber in a so called "fungal cellar" or "soil-bed" to evaluate its performance in ground contact is widespread practice. In order to obtain a more accurate and reproducible estimate of preservative performance, several institutes, among them the BAM in Berlin, have routinely carried out static bending tests in addition to visual examination. These tests were usually performed with a defined maximum load or deflection path regardless of the remaining degree of elasticity of the test specimens. Recent studies at the BAM revealed that by modifying the method, i.e. by restricting the applied load to the non-destructive interval for each individual test specimen, the calculated modulus of elasticity (MOE) reflect the changing strength properties caused by biological deterioration and allow within a relatively short time valuable predictions on the service life of the treated timber in soil contact.
I Stephan, S Göller, D Rudolph
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
Detection of feeding behaviour of termites using AE monitoring
1991 - IRG/WP 1514
Using acoustic emission (AE) monitoring, the feeding activity of the termite inhabiting a wood specimen was investigated. The amplitude and the rate of AE from the specimen of Coptotermes formosanus Shiraki was larger than that of Reticulitermes speratus Kolbe. The AE event rate was higher in the specimen with soldiers than without soldiers. The AE event rate decreased according to the resistance of wood specimens against termite attack.
Y Imamura, M Tokoro, M Owada, Y Fujii, M Noguchi
Quantitative determination of Chromium: A comparison of three instruments
1995 - IRG/WP 95-50053
A comparison is made between three instruments for measuring levels of chromium in the leachate of copper-chrome-arsenic (CCA) treated timber. These include an atomic absorption spectrophotometer, an inductively coupled plasma spectrometer and the RQflexâ. The RQflexâ is a new hand-held instrument which measures chromium by dipping a ReflectoquantÒ strip into the leachate and inserting the strip into the RQflexâ. Readings are determined reflectometrically following a reaction between chrome and the Reflectoquantâ strip. It provides an inexpensive and quick technique which is used in this paper to determine the degree of preservative fixation prior to the removal of CCA treated timber from drip pads of wood treatment sites. The results indicate that RQflexâ is a suitable instrument for the rapid assessment of chromium levels in rain wash off from treated timber. A comparison is given of the economics and accuracy of the instruments for measuring chromium.
S Walley, P R S Cobham, P Vinden
The Rubber Ruler: Continuous measurement of dimension changes in wood panels
1994 - IRG/WP 94-20033
A new application for a linear transducer called Rubber Ruler was developed. Rubber Ruler provides a simple and reliable method for continuous monitoring of dimension changes in wood panels. This paper presents the methodology. Results of priliminary experiments designed to simulate the movement in wood panels are also discussed.
Siew K Ho, P Vinden, P Kho
A simple leaching procedure for in-plant monitoring of CCA fixation
1993 - IRG/WP 93-30023
A simple leaching test is described to quantitatively estimate the extent of fixation of chromated copper arsenate (CCA) preservative treated wood products. It is based on the reaction between diphenylcarbazide and unreacted hexavalent chromium leached from borings taken from treated wood during the fixation process. The test requires about 20 minutes to complete and can be set up in a treating plant quality control laboratory for less than US $1000.00.
P A Cooper, Y T Ung
Forest products laboratory methodology for monitoring decay in wood exposed above ground
1995 - IRG/WP 95-20074
Research at the Forest Products Laboratory on the durability of wood in service has included a full complement of laboratory and field tests. In this report, we present a review of past and current methods used to evaluate the condition of preservative-treated wood exposed above ground. Current protocols are described for tests on wood packaging, roofing, and dimension lumber.
R C De Groot, T L Highley
A deflection test for monitoring decay in miniature beams
1986 - IRG/WP 2269
A laboratory apparatus for assessing decay in small stakes is described. It involves the measurement of deflection in a static bending apparatus using a displacement transducer linked to a microcomputer. Measurements are non-destructive, rapid, accurate and automatic and decay can be assessed repeatedly over long time periods.
S M Gray
Leaching tests - A paper for discussion
1973 - IRG/WP 221
J W W Morgan
Exposure monitoring of creosote vapors
1989 - IRG/WP 3511
Creosote oils contain hundreds of compounds. During impregnation and handling of treated wood the main component in the vapors released in air is naphthalene. Other main components are alkyl naphthalenes, indene, phenol and its methyl derivatives, benzothiophene, diphenyl, acenaphthalene and fluorene. In the measurement of creosote vapors, naphthalene can be used as an indicator agent. One of the major urinary metabolites of naphthalene is 1-naphthol. To explore the relation between naphthalene concentration in the air and 1-naphthol in the urine of exposed workers we monitored air concentrations and collected urine samples from six men over a working week. 1-Naphthol concentrations in urine samples were analyzed by GC as a pentafluorobenzylbromide derivative. The average concentration of 1-naphthol in the Monday morning samples was 0.1 mg/l, in the Monday afternoon 3.1 mg/l, in the Friday morning 0.4 mg/l and in the Friday afternoon 2.9 mg/l.
P Heikkilä, M Loutamo, V Riihimäki, M Romo
Wood preservatives ecotoxicology on Gammarus pulex (L.) - toward an environmental monitoring method and a getting rid of pollution process
2005 - IRG/WP 05-50224-9
Wood preservatives can have a strong impact on freshwater invertebrates when used close to aquatic ecosystems. It has been reported in Jura that different arthropod taxa, specially crustaceans, have disappeared along several kilometers downstream from factories using insecticides and fungicides as wood preservatives. The crustacean Gammarus pulex (L.) is a relevant bioindicator to characterize the impact of wood preservatives on freshwater community. It presents a high sensitivity to wood preservatives but a relative tolerance to organic and nutrimental pollution. This abundant and ubiquitous crustacean has a key role in numerous aquatic ecosystems particularly in the decomposition of cellulose and as a prey for several fish species susceptible to be eaten by humans. In this study, we aim on the one hand to determine the adsorption capacity of different substrates of propiconazole, a fungicide widely used in the wood treatment, and on the other, to evaluate the toxicity of wood preservatives for G. pulex in controlled conditions. We hypothesize that the fungicide toxicity may be influenced by different types of substrate used in the test containers, i.e., coarse organic matter and gravel. These results should allow us to go, firstly toward the elaboration of sensors in order to detect product emissions in the aquatic environment, and secondly toward a depuration process in order to decrease the impact on the aquatic communities. These experiments should also allow us to develop a new biological monitoring method for the assessment of the impact of wood preservation on the aquatic ecosystems.
O Adam, F Degiorgi, G Crini, P-M Badot
Technique for monitoring absorption during a vacuum pressure process
1992 - IRG/WP 92-3696
A laboratory technique was developed and an apparatus constructed which allowed for the direct and continuous measurement and observation of volumetric uptake of water-borne preservative into wood samples throughout a controlled vacuum-pressure treatment process. Fractional filling of void space was calculated. Graphing (fractional saturation) against time allows prediction of optimum cycle lengths with respect to achievable saturation values. Treatability evaluations using this technique were carried out on heartwood samples of six Malaysian hardwood species, kapur, kempas, keruing, punah, rubberwood, simpoh and on sapwood samples of Scots pine as a control. Generally the graphs exhibited two quasi-linear zones showing rapid initial absorption followed by slow absorption over a long period.
A J Pendlebury, J A Petty
Preservatives treatment and field test monitoring of spruce pole stock: CCA and fumigant treatments
1990 - IRG/WP 3619
The fumigants trichloronitromethane (chloropicrin) and sodium N-methyldithiocarbamate (SNMDC) were used to treat red spruce pole stock, either CCA treated or untreated, through holes bored through the pole's center. The poles were analyzed for the presence of microorganisms immediately before ground installation and again after installation at a pole test site. Monitoring of fumigant movement in the poles was also performed after one year. Results indicate that both fumigants moved throughout the ground line regions of the poles, although less toxicity to the bioassay fungus was observed in the SNMDC treated poles. Reduced fumigant levels, and more sporadic diffusion was noted in the above ground portions of both chloropicrin and SNMDC treated poles although again chloropicrin exhibited greater toxicity to the bioassay fungus. Despite the variability of fumigant diffusion as determined by bioassay, no decay fungi could be isolated from the treated poles after one year. This was in contrast to high frequency isolation of decay from control poles.
A J Pendlebury, B Goodell
Field trials on preserved timber out of ground contact
1978 - IRG/WP 3154
This report describes two different field trials studying the performance of preservative treatments on timber exposed to the weather, but above the ground. Results are presented on the protection afforded against decay, and on the efficiency of water-repellent preservative treatments in controlling the uptake of moisture by the timber. Proposals for a standard field test system are briefly discussed.
D F Purslow, N A Williams
Feasibility of termite control using crushed cement-stabilized sludge (Polynite) as a physical barrier and acoustic emission (AE) monitoring
2000 - IRG/WP 00-10381
In Japan, the damages by the subterranean termites (Coptotermes formosanus Shiraki and Reticulitermes speratus Kolbe) are more common. Recently, the more attention is paid to the methods of the termite controls of less- or non-chemical. As one of the non- chemical treatment, physical barrier using particles as basalts 1) , granites, and gravels 2) were investigated in terms of its safety, cost effectiveness and duration of performance, and there were also examples that the physical barriers using some particles have been put to practical use in a few countries except in Japan. Ebeling and Pence showed that the relationship between particle size and termite body size is an important factor in controlling tunneling activity of subterranean termites, and the crushed volcanic cinders of 0.85-2.36 mm in diameter prevented R. hesperus from penetrating 3) . Tamashiro and co- workers indicated that the particles of particular sizes (1.70-2.40 mm in diameter) prevented C. formosanus from penetrating 4) . Su and co- workers investigated the penetration of the sand barrier consisting of crushed quartz rocks and fossilized coral by C. formosanus in laboratory- and field-testing 5, 6) . These results show that it is important to investigate the relationships between the size of termites and particles to evaluate the effects of the physical barrier using particles. On the other hand, in Japan surplus soils and sludge of sixty million tons per annum are discharged from construction sites. The recycle techniques using the surplus soils and sludge and the development of the market for these recycled products are the theme of importance. The crushed cement- stabilized sludge (Polynite) as one of the recycled products of surplus soils and sludge is one of the newly developed and recycled material. It is technically suitable for mass production, has grate cost effectiveness, and is easy to uniform the particle size. In this study, the feasibility of a physical barrier using Polynite uniformed the particle size for termite was examined in a laboratory testing. AE monitoring 7-13) as a method forthe detection of the penetration of termites into the Polynite barrier at an early stage was also investigated, for the application of Polynite barrier in the house.
Y Yanase, M Shibata, Y Fujii, S Okumura, K Iwamoto, T Nogiwa, T Yoshimura, Y Imamura
Feasibility of AE (Acoustic Emission) monitoring for the detection of the activities of wood-destroying insects
1992 - IRG/WP 92-2416
The feasibility of acoustic emission (AE) as a nondestructive testing method for the detection of the wood destroying insects was investigated. AEs were detected from the wood specimens under feeding attack of sugi bark borers or powder-post beetles. However, the feasible monitoring area of an AE sensor is influenced by the attenuation of AE amplitude, so that this could be a problem in the practical AE measurements, especially with wood specimens of higher moisture content.
Y Fujii, Y Imamura, E Shibata, M Noguchi
Detection of Acoustic Emission (AE) generated by termite attack in a wooden house
1999 - IRG/WP 99-20166
Recently, considerable attention has been paid to methods for termite control, which involves few or no chemicals. To reduce the amount of termiticide needed, it is necessary to detect termite attack in wood as early as possible. The feasibility of acoustic emission (AE) monitoring for the nondestructive detection of termite attack has been discussed previously. In this study, we propose some technical solution for the application of AE monitoring to practical control operations. Using a needle-type waveguide combined with an AE sensor (PZT sensor), AEs generated and propagated within floors and walls could be detected effectively. A 0.04 mm-thick sample of the piezoelectric polymer PVDF, which was inserted between the construction members of wooden houses, could detect Aes propagated both in such members and at joint surfaces, although PVDF film is less sensitive than a PZT sensor. The feasibility of using a portable AE detector as the input device for a total security system against termite attack in a house is also discussed.
Y Fujii, Y Yanase, T Yoshimura, Y Imamura, S Okumura, M Kozaki
Detection of termite attack in wood using AE monitoring
1990 - IRG/WP 2355
An acoustic emission (AE) monitoring method for detecting termite activity in wood was applied to lumber of 3 by 3 cm to 10 by 10 cm square, 1 m long. Furthermore, the propagation of AEs due to the feeding activities of termites in the specimens and the locations of AE sources were analyzed. Also discussed was the feasibility of the method applied to posts out in the field of subterranean termites. The results obtained from laboratory and field tests suggest that AE monitoring could be an effective non-destructive method to detect feeding activity of termites even in the incipient stages of the termite attack in wood.
Y Fujii, M Owada, M Noguchi, Y Imamura, M Tokoro
The first two years of an area wide management program for the Formosan subterranean termite in the French Quarter, New Orleans, Louisiana
2000 - IRG/WP 00-10357
The Formosan subterranean termite, Coptotermes formosanus, is a serious pest in several parts of the world and is the most destructive insect in Louisiana. The density of the Formosan subterranean termite in the French Quarter, New Orleans, Louisiana, USA is very high. A large area pilot test for area wide management of this insect was begun in 1998 in the French Quarter to reduce densities of termites and demonstrate the effectiveness of the approach of treating all properties in a large area using area wide management. The pilot test is a cooperative effort between the LSU Agricultural Center, USDA-Agricultural Research Service and New Orleans Mosquito and Termite Control Board. All but four of 323 properties in a contiguous 15 block area in the French Quarter were treated using commercially available baits or non repellent termiticides selected by property owners and applied by professional pest control operators. Properties were inspected for conducive conditions and proper treatment after treatments were made. Data on termite activity were collected using glue boards for alates and in ground monitors for foraging activity. Alates were sampled two to three times weekly during the flight season (May through July 15) in both 1998 and 1999 using glue boards hung near lamps on street lights. Monthly monitoring of foraging activity began in January, 1999 to determine the number of stations with termites and amount of wood consumed. Reductions in densities of alates between years were not found; probably as a result of the limited time treatments had been in place. The percentage of in ground monitoring stations with termites was lower in the treated zone than outside the treated zone after September 1999. Continued treatment and monitoring are required to determine the extent of and the long term effects of the area wide management program.
D R Ring, A L Morgan, W D Woodson, A R Lax, X P Hu, E D Freytag, L Mao
Internal pressure monitoring during the treatment of Pinus radiata (D. Don)
1995 - IRG/WP 95-40049
The use of micro-transducers to monitor the internal pressure of wood during treatment is investigated. The rates of pressure transfer in radiata pine sapwood and heartwood are compared during Bethell treatment with copper chrome and arsenic preservative. The effect of pre-conditioning treatments are also evaluated using micro-transducer monitoring. It is anticipated that knowledge of the changes in internal pressure in wood during treatment will lead to improvements in treatment schedules and processes particularly for treatment of impermeable timbers.
P R S Cobham, P Vinden
BRE Experience in monitoring decay in out-of-ground exposure trials
1995 - IRG/WP 95-20077
The outdoor field trial has always been regarded as the ultimate test of performance for assessing the effectiveness of a wood preservative. For this reason, the Building Research Establishment (BRE) has invested much effort in such trials over many years. Emphasis in early trials was on ground contact tests which were the basis both for assessing the likely performance of a preservative in protecting posts and poles, and for classifying a timber's natural resistance to fungal decay. When preservation of timber in the building and construction industry assumed greater importance, the emphasis was placed on the development of out-of-ground field trials to provide data on the likely performance of exterior joinery work in buildings. For these tests, the exposure conditions provided a less severe hazard for out-of-ground timber than for wood permanently in contact with the ground. Out-of-ground trials have been running at BRE since 1967 (Orsler and Smith, 1993) initially using T-joints and L-joints and later the window joinery test rig was established to provide conditions close to those in buildings (Purslow, 1975). All the early trials were assessed only by visual assessment for decay. Later still, small L-joints with a coating (the methodology which was used as the basis for EN 330) were used for a comprehensive study to establish the pattern of colonisation by microorganisms and associated changes to the wood. It was established that the basidiomycete fungi ultimately responsible for the decay are the climax of a colonisation sequence of a range of types of fungi plus bacteria (Carey, 1980). In an attempt to give early indications of long term performance, colonisation by basidiomycetes and changes in the porosity of the wood during exposure have been used as the basis for assessing performance relative to that of a reference preservative (1.0% tri n-butyltin oxide). Hyphen joints were introduced (Orsler and Holland, 1993) for studies of preservative distribution.
J K Carey, R J Orsler
Using AE monitoring for detecting economically important species of termites in California
1991 - IRG/WP 2375
Acoustic emission (AE) monitoring was conducted on wooden samples containing three economically important species of termites in California (dampwood termite, Zootermopsis nevadensis, Western drywood termite, Incisitermes minor, and Western subterranean termite, Reticulitermes hesperus). Laboratory AE studies included varying termite species, as well as 7 day studies exploring the periodicity of termite behavior. The results from the laboratory tests revealed significant differences in AE events between species, days, and sensors used. In a second study, the distance that AE signals could be detected in 2.6 m (8 ft.) long, 52 x 102 mm² (2 by 4 in.) wooden studs was also explored for the dampwood termite. Acoustic emission signals were detectable for up to 2.2 m in wood for dampwood termites. This study is compared with other investigations exploring the feasibility of using AE to detect termites.
V R Lewis, R L Lemaster, F C Beall, D L Wood