The Experts below are selected from a list of 2580 Experts worldwide ranked by ideXlab platform
David Bertrand - One of the best experts on this subject based on the ideXlab platform.
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Effects of fungal decay on elasticity and damping of small-diameter silver fir logs assessed by the transverse vibration resonant method
Wood Science and Technology, 2018Co-Authors: Jean Baptiste Barré, Franck Bourrier, Loïc Brancheriau, David BertrandAbstract:A number of studies have shown the ability of the vibration resonant method (VRM) to measure the modulus of elasticity (MOE) and the damping ratio ( $$\xi$$ ξ ) of calibrated wooden samples of various dimensions. This method based on free transverse vibrations was also studied to assess the decay extent in small stakes. Nevertheless, a need for investigations was identified in order to apply the method to decayed logs. Both decay and geometrical singularities brought heterogeneity not taken into account by the VRM. The aim of this study was to examine the effects of fungal decay on these two mechanical properties of small-diameter silver fir logs using the VRM. Fifty-five small-diameter logs were monitored over a decay process taking place in a greenhouse located near Grenoble (France). The MOE and $$\xi$$ ξ were measured in intact and decayed states. The results showed the reliability of the measurements of both properties. $$\xi$$ ξ was found to be independent of moisture content for wood above the Fibre Saturation point. The results validated the loss in MOE and the gain in $$\xi$$ ξ due to fungal activity. Thus, indicators based on the MOE and $$\xi$$ ξ were proposed and compared to quantify the decay extent. Indicators calculated from the first mode of vibration appeared to be relevant for that purpose. Future work is needed to validate indicators on structural size logs and to compare this quantitative assessment to those obtained by the standard EN 152 that currently serves as a benchmark.
Loïc Brancheriau - One of the best experts on this subject based on the ideXlab platform.
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Effects of fungal decay on elasticity and damping of small-diameter silver fir logs assessed by the transverse vibration resonant method
Wood Science and Technology, 2018Co-Authors: Jean Baptiste Barré, Franck Bourrier, Loïc Brancheriau, David BertrandAbstract:A number of studies have shown the ability of the vibration resonant method (VRM) to measure the modulus of elasticity (MOE) and the damping ratio ( $$\xi$$ ξ ) of calibrated wooden samples of various dimensions. This method based on free transverse vibrations was also studied to assess the decay extent in small stakes. Nevertheless, a need for investigations was identified in order to apply the method to decayed logs. Both decay and geometrical singularities brought heterogeneity not taken into account by the VRM. The aim of this study was to examine the effects of fungal decay on these two mechanical properties of small-diameter silver fir logs using the VRM. Fifty-five small-diameter logs were monitored over a decay process taking place in a greenhouse located near Grenoble (France). The MOE and $$\xi$$ ξ were measured in intact and decayed states. The results showed the reliability of the measurements of both properties. $$\xi$$ ξ was found to be independent of moisture content for wood above the Fibre Saturation point. The results validated the loss in MOE and the gain in $$\xi$$ ξ due to fungal activity. Thus, indicators based on the MOE and $$\xi$$ ξ were proposed and compared to quantify the decay extent. Indicators calculated from the first mode of vibration appeared to be relevant for that purpose. Future work is needed to validate indicators on structural size logs and to compare this quantitative assessment to those obtained by the standard EN 152 that currently serves as a benchmark.
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Rapid prediction of shrinkage and Fibre Saturation point on teak (Tectona grandis) wood based on near-infrared spectroscopy
Annals of Forest Science, 2010Co-Authors: Adzo Dzifa Kokutse, Loïc Brancheriau, Gilles ChaixAbstract:• Dimensional stability, along with the natural durability and colour of the wood, is one of the most important characteristics of teak used as timber. However, it is very time-consuming to take measurements of this kind. For the purposes of selection for the production of improved varieties, the number of samples to be measured rapidly exceeds the capacity of a traditional laboratory. • Near-infrared spectroscopy, based on a set of reference data, is a tool enabling many of the chemical properties of wood to be predicted and the number of laboratory measurements to be reduced exponentially. The issue here is a question of checking the effectiveness of NIRS tool to build models and predict the shrinkage and Fibre Saturation point of teak wood from Togo. • The results show the possible use of NIRS to measure the dimensional stability of teak wood and that it is appropriate to choose the type of wood and type of surface to be measured by NIRS. The best prediction models for radial and tangential shrinkage and Fibre Saturation point give R 2 values of 0.72, 0.83 and 0.87 respectively with ratios of performance deviation of 1.8, 2.4 and 2.8. • Consequently, after verification on other sets of teak samples, which may or may not be included in the prediction model, NIRS can be used to predict shrinkage and Fibre Saturation point values accurately for a large number of samples, making it possible to include these characteristics in the selection criteria for classifying wood and high throughput phenotyping.
Jean Baptiste Barré - One of the best experts on this subject based on the ideXlab platform.
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Effects of fungal decay on elasticity and damping of small-diameter silver fir logs assessed by the transverse vibration resonant method
Wood Science and Technology, 2018Co-Authors: Jean Baptiste Barré, Franck Bourrier, Loïc Brancheriau, David BertrandAbstract:A number of studies have shown the ability of the vibration resonant method (VRM) to measure the modulus of elasticity (MOE) and the damping ratio ( $$\xi$$ ξ ) of calibrated wooden samples of various dimensions. This method based on free transverse vibrations was also studied to assess the decay extent in small stakes. Nevertheless, a need for investigations was identified in order to apply the method to decayed logs. Both decay and geometrical singularities brought heterogeneity not taken into account by the VRM. The aim of this study was to examine the effects of fungal decay on these two mechanical properties of small-diameter silver fir logs using the VRM. Fifty-five small-diameter logs were monitored over a decay process taking place in a greenhouse located near Grenoble (France). The MOE and $$\xi$$ ξ were measured in intact and decayed states. The results showed the reliability of the measurements of both properties. $$\xi$$ ξ was found to be independent of moisture content for wood above the Fibre Saturation point. The results validated the loss in MOE and the gain in $$\xi$$ ξ due to fungal activity. Thus, indicators based on the MOE and $$\xi$$ ξ were proposed and compared to quantify the decay extent. Indicators calculated from the first mode of vibration appeared to be relevant for that purpose. Future work is needed to validate indicators on structural size logs and to compare this quantitative assessment to those obtained by the standard EN 152 that currently serves as a benchmark.
Franck Bourrier - One of the best experts on this subject based on the ideXlab platform.
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Effects of fungal decay on elasticity and damping of small-diameter silver fir logs assessed by the transverse vibration resonant method
Wood Science and Technology, 2018Co-Authors: Jean Baptiste Barré, Franck Bourrier, Loïc Brancheriau, David BertrandAbstract:A number of studies have shown the ability of the vibration resonant method (VRM) to measure the modulus of elasticity (MOE) and the damping ratio ( $$\xi$$ ξ ) of calibrated wooden samples of various dimensions. This method based on free transverse vibrations was also studied to assess the decay extent in small stakes. Nevertheless, a need for investigations was identified in order to apply the method to decayed logs. Both decay and geometrical singularities brought heterogeneity not taken into account by the VRM. The aim of this study was to examine the effects of fungal decay on these two mechanical properties of small-diameter silver fir logs using the VRM. Fifty-five small-diameter logs were monitored over a decay process taking place in a greenhouse located near Grenoble (France). The MOE and $$\xi$$ ξ were measured in intact and decayed states. The results showed the reliability of the measurements of both properties. $$\xi$$ ξ was found to be independent of moisture content for wood above the Fibre Saturation point. The results validated the loss in MOE and the gain in $$\xi$$ ξ due to fungal activity. Thus, indicators based on the MOE and $$\xi$$ ξ were proposed and compared to quantify the decay extent. Indicators calculated from the first mode of vibration appeared to be relevant for that purpose. Future work is needed to validate indicators on structural size logs and to compare this quantitative assessment to those obtained by the standard EN 152 that currently serves as a benchmark.
A J Hunter - One of the best experts on this subject based on the ideXlab platform.
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equilibrium moisture content and the movement of water through wood above Fibre Saturation
Wood Science and Technology, 1995Co-Authors: A J HunterAbstract:The present work brings together the results of two previous studies on the diffusion coefficient and on capillary pressure, both above Fibre Saturation. The hypothesis making the data mutually consistent, is the constancy of the diffusion coefficient where capillary pressure is the driving force. Also given is an isotherm for wood which extends over the full range of moisture content, from dry to complete Saturation. A further consequence of the work is the probability density function for capillary pressure with respect to water adsorbed and the corresponding distribution of capillary sizes.