Wood Moisture Content Research Papers (original) (raw)

2025

1 DOI:10.4067/S0718-221X2022005XXXXXX 1 A NOVEL METHOD FOR PRODUCING A GLULAM FROM THE WOOD OF 2 PEELER CORES 3 4 Daniel Koynov1a, Rosen Grigorov1b, Miglena Valyova2c 5 1 University of Forestry, Department of Mechanical Technology of Wood, Faculty of Forest 6 Industry, Sofia, Bulgaria. 7 2 University of Forestry, Department of Plant Pathology and Chemistry, Faculty of Ecology and 8 Landscape Architecture, Sofia, Bulgaria. 9 a https://orcid.org/0000-0001-5370-9468 10 b https://orcid.org/0000-0001-7922-0855 11 c https://orcid.org/0000-0003-4072-2537 12 13 *Corresponding author: mvalyova@abv.bg 14 Received: December 27, 2020 15 Accepted: September 21, 2021 16 Posted online: September 21, 2021 17

2025, Global Journal of Science Frontier Research: Gbio-Tech & Genetics

The aim of this research to investigated physical and mechanical properties of thermal plywood of PF adhesive. Physical property focused on density, water absorption and swelling. And mechanical property was MOR, MOE, shearing strength and hardness.The Teak veneer was the main raw material the size was 2 mm in thickness, and 400 mm in width and length. The veneer was divided into five groups as were control, thermos-veneer, at 180°C, at 200°C, 220°C and 240°C and 4 min, 8 min and 12 min, the spread 150 g/m2 and five layers. Plywood products used PF adhesive products were cool pressing in 10 min and hot pressing in 15 min. density test followed with AS/ANZ 2098.7, 2012, WA and swelling thickness were followed ASTM D 3502-76, The dimension sample design was 10x25x300 mm for MOR and MOE, 10x50x100 mm for shearing strength and 10x50x50 for harness and testing by FastTest software. Data analyses were One-way ANOVA and multiple linear regression.As the result, the density ofthermal treatment was decreased density of teak plywood. A control was significant different on thermal treatment of different level of temperature and length of time the control was no significant different.

2024

This work aims to use experimental data from thermal characterization and adsorption/desorption isotherms of two tropicals woods species (Ayous and Tali) to propose an empirical model of thermal conductivity as a function of air relative humidity. A static gravimetric method was used to determine the adsorption isotherms of Tali and Ayous at 30 °C, and 40 °C. The GAB, Henderson and Nelson models were used to predict the isotherms. Exponential models of thermal conductivity and volumetric heat capacity with air relative humidity were proposed. The influence of hysteresis phenomenum was studied on these properties. The reliability of the developed empirical correlation between thermal properties and air relative humidity was evaluated by comparing the experimental and predicted curves. The relative errors were less than 8% for both Ayous and Tali. The correlation coefficients obtained were greater than 99% for both species in adsorption and desorption. There was also an increase in the equilibrium water content of both species with the increase in water activity at constant temperature. The correlation coefficients between GAB model and sorption experimental data were lower than 99% when Ayous was subjected to a temperature of 40 °C in adsorption and Tali to a temperature of 40 °C in desorption.

2024

The aim of this study was to determine the drying time of firewood under the climatic conditions of the Czech Republic to decrease the moisture content to an acceptable level for combustion (under 20%). The effects of log size,... more

2024, Maderas-ciencia Y Tecnologia

A method to estimate the surface moisture content below the fibre saturation point that is a function of the surface temperature, wet-and dry bulb temperatures, equilibrium moisture content, and fibre saturation point was evaluated. The method is based on the premise that the surface temperature is solely influenced by the surface moisture content and the climate that the surface is exposed to. The prediction model contends that the surface moisture content is equal to the fibre saturation point when the surface temperature is equal to the wet bulb temperature, and equal to the equilibrium moisture content when the surface temperature is equal to the dry bulb temperature, with a linear interpolation between those two points. The model thus predicts that the average moisture content of a thin piece of veneer can be predicted with fairly good accuracy. Also, when drying boards in a fast changing climate, e.g. fan reversals in industrial kilns, the surface temperature and surface moisture content should change as abruptly as the climate does. Additionally, the surface moisture content should correlate to the known drying phases, with a consistently high surface moisture content during the capillary phase when the wet line is close to the surface, and a quickly decreasing surface moisture content when the wet line moves into the wood during the transition to the diffusion phase. The prediction model was tested in these three scenarios and the results suggest that the basic premise is reasonable, and that the method is useful for surface moisture content estimation.

2024, Maderas. Ciencia y tecnología

2023, Forests

The characterization of poplar wood assumes a strategic position to increase the competitiveness of the entire forest wood supply chain. From this aspect, the identification of wood quality represents a primary objective for researchers and private landowners. The quality of wood can be defined via traditional visual methods based on the experience of technicians or using traditional tools, such as incremental drills and sound hammers. The traditional properties of these traits, based only on visual characteristics, can outline a classification based on the macroscopic properties of wood with the aim of defining the volume of recoverable wood. However, this approach does not provide a good indicator of the physical or mechanical properties of wood. Mechanical tests of wood require the felling of trees with the correlated preparation of the specimens. A different solution to determine wood quality is based on the application of non-destructive technology (NDT). In this context, the a...

2023, Material design & processing communications

Surface treatments can modify the materials behavior toward water sorption phenomena. The Guggenheim-Andersen-de Boer sorption equation, already used in the past to study various wood species, is here proposed to investigate the sorption behavior of pine wood samples treated with different sealing material. Particularly, the paper aims to explore the modification of the k parameter with the applied coating. Measurements of sorption-desorption branches permitted to clearly distinguish the behavior of treated samples, the relative humidity (RH) conditions over which they are more dimensionally stable, as well as their tendency to swell and shrink. The proposed study permitted to evaluate the usefulness of the k parameter as an indicator of the presence of chemical treatments on wood at high RH values. Particularly, the k value has been found to change as a function of chemicals surface treatments limiting in different ways the access and expulsion of water moisture. Highlights • Surface sealed pine wood samples were analyzed by vacuum microbalance. • The Guggenheim-Andersen-de Boer equation has been applied to water sorption-desorption data. • The equilibrium moisture content and its first derivative explained samples swelling/shrinking tendency. • Assessment of the usefulness of k as indicator of the wood treatment at high relative humidity values. • Assessment of k modifications in relation to the type of sealing treatment.

2023, Materials Science

The data performance for structural usage of highly engineered wood is very useful, however, the lacking of the data is very much concern for fast-growing indigenous timber species in timber engineering field. In correlation with that, the strength properties behaviour of Endospermum diadenum has to be studied to analyse the distribution pattern of strength properties at a different distance from the vortex also known as pith. The species have been obtained from the East Campus of Universiti Malaysia Sarawak's forest reserve. Strength properties test were carried out namely, static bending (modulus of rupture-MOR and modulus of elasticity-MOE), and the compressive strength (compression stress parallel to grain). Meanwhile, physical properties test was carried out namely, moisture content (MC) and density. Small specimens measuring 20 x 20 mm were tested in green and dry conditions in accordance with British Standard, BS 373:1957 (British Standards Institution, 1957). The green condition refers to moisture content greater than 19 percent and dry condition with moisture content less than or equal 19 percent. All the results that had been tested were analyzed using statistical analysis as mean results. The strength properties of specimen increased from the pith towards the sapwood in which the strength is the lowest at 25 mm from pith followed by 50 mm, and the highest is at 75 mm from the pith. Distribution of the basic density also increases slightly from the pith towards the sapwood with a significant increment in average mean value at 25 mm from vortex with 0.54 g/cm 3 , 0.62 g/cm 3 at 50 mm and 0.66 g/cm 3 at 75 mm from the vortex. Meanwhile, for dry condition, the increases in average mean value with 0.425 g/cm 3 at 25 mm, 0.427 g/cm 3 at 50 mm and 0.47 g/cm 3 at 75 mm from the vortex. It can be concluded that the physical properties of the wood have a direct impact on the wood stiffness and strength.

2023, JOURNAL OF POLYTECHNIC

In this study, the effects of the process parameters in the planing processes on the surface roughness were investigated. For this purpose, the experimental samples of cherry (Prunus avium L.) and pear (Pirus communis L.) wood species, which are commonly used in the Turkish decoration industry, were prepared. In preparing the experimental samples, the wood was planed tangentially and radially to the annual rings at a cutting depth of 1.4 mm in a milling machine with 4 blades 85 mm in diameter. The wood was planed into the direction of spindle rotation and in the direction against the spindle rotation at feed rates of 6, 9 and 12 m/min. The surface roughness values of the experimental samples were determined by using a stylus-type profilometer according to the ISO 4287 standards. The surface roughness was evaluated according to the R a , R z and R y principles, which were three basic parameters of the determination method for surface roughness. According to the results, when the planing parameters were differentiated, the obtained surface roughness values also acquired a different character. The feed direction of work pieces for planing in the direction of spindle rotation was lower than the feed direction in the opposite to spindle rotation for the surface roughness.

2023, Moisture Level And Water Absorption In The Most Popular Types Of Woods In Albania

This paper is going to deal with water absorption in different types of wood such as: pine, oak, beech and fir. The amount of water absorbed by these types of wood is known as water absorption, and it is determined using the material's initial state and after their immersion in water. The major goal of this study is to explain the effects of water absorption in hardwood materials and to demonstrate the changes that will take place in them over the course of 48 hours. Water can be absorbed by wood in a variety of ways, as a liquid, or as an atmospheric vapor. Despite the fact that wood can absorb other liquids and gases, water is the most important. Because of its hygroscopicity, wood, whether as part of a living tree or as a material, always contains moisture. The experiment will be focused on the selection of different types of wood (most popular in Albanian context), analyzing their water absorption and moisture level. The wooden samples will be submerged in water for 24 and 48 hours in order to obtain the appropriate results. Their moisture level and water level due to capillarity will be analyzed too. The purpose of the study is to follow the behavior of wooden frames in different environments.

2023, Maderas. Ciencia y tecnología

Physical properties are major characteristics that validate biomaterials' adaptability to commercial utilization. The moisture content, density, swelling, and shrinkage within male and female Borassus aethiopum were assessed. Green and dry moisture content, and density were tested with the oven-dry method while swelling and shrinkage were evaluated using the water-saturation test and oven-dry methods respectively. Unlike moisture content, density decreased towards the crowns and radially from the peripheries to their cores. Directional swelling decreased as: Radial > Tangential > Longitudinal. Volumetric swelling was greatest at the core of the base (6,99 %) but at least at the periphery within the middle of the male (2,89 %). However, the female recorded much swelling at the core of its mid-portion (6,23 %) and least (4,01 %) at the crown periphery. Directional shrinkage decreased identically as the male variety while the volumetric shrinkage for both varieties was not consistent. The peripheries had less moisture content, better dimensional stability and density (which influences wood strength) at the butt than those of the core indicating the peripheries would maintain its original dimension and strength when subjected to environmental changes and be more viable for structural works than the core.

2023

This study examined the response of dynamic and static modulus of elasticity (MOE) of red pine small clear wood to a temperature change from-40 to 40. The 25.4×25.4×407 mm red pine specimens used in this study were selected from those used in a previous laboratory investigation of acoustic properties. The moisture content (MC) of the specimens ranged from 0% to 118.3%. The dynamic MOE was calculated based on measured acoustic velocity and the wood density at the time of acoustic measurement. The static MOE was measured by conducting a static bending test in a laboratory-controlled environment chamber with wood temperature changing from-40 to 40. Our results indicated that both static and dynamic MOE of wood were affected by temperature and the state of moisture in wood. Above freezing point, MOE decreased linearly at a slow rate as wood temperature increased. Below freezing point, MOE increased at a rapid rate as wood temperature dropped. We found that MC of wood had a significant compounding effect on the MOE-temperature relationships. Temperature effect was much more significant in green wood than in dry wood. Mathematical models were developed to predict the percentage change of MOE relative to the standard temperature of 20 for wood temperature below and above freezing point. It is concluded that dynamic MOE of wood based on acoustic measurements can be used as a good predictor of static MOE for nondestructive evaluation of wood under a range of wood temperatures.

2022, Ciência Rural

ABSTRACT: This study evaluated the effects of thermal modification at different temperatures and for different durations on the mechanical strength of wood of selected species from an agroforestry system. To this end, three 9-year-old (approximate age) individuals, each from four species of forest trees-Parapiptadenia rigida (Benth.) Brenan, Peltophorum dubium (Spreng.) Taub., Eucalyptus grandis × Eucalyptus urophylla hybrid, and Schizolobium parahyba (Vell.) Blake-were evaluated. After obtaining initial measurements, samples from the four species under went heat treatment for 2 h and 4 h and were subsequently subjected to heat using an oven at temperatures 120°C, 150°C, 180°C, and 210°C; respectively, in addition to the control. For evaluating mechanical strength, the technical standard ASTM D 143-94 was used to obtain the values of the moduli of elasticity and rupture, tension at the proportional limit, and maximum force of the subjects. It was observed that different durations an...

2022, Maderas. Ciencia y tecnología

Drying stress is the main cause for the generation of drying cracks in wood disks during drying, which limits the processing and utilization of this valuable material. For this study, white birch disks with one trunk and a thickness of 30 mm were dried under three different drying conditions: 1) a very slow drying process preventing the generation of a radial moisture content (MC) gradient, 2) a drying process with slowly increasing temperature leading to a radial MC gradient, with a higher MC in the heartwood, and 3) the same heat drying process but the wood disks were partly covered with a thin plastic film prior to the drying process leading to a reversed radial MC gradient, i.e., a higher MC in the sapwood. For each drying condition, the tangential elastic strain in the wood disks was investigated for a mean MC of 26%, 18% and 10%, respectively, as a function of the radial distance from the pith in order to predict the drying stress. Furthermore, the stress characteristics and stress reversal mechanisms in wood disks are discussed in this paper with the help of stress analysis sketches.

2022, Maderas. Ciencia y tecnología

This study aims to evaluate the free and bound water flows in the different axes of Corymbia citriodora wood during drying. Wood samples were taken from the inner and outer regions of the tree stem from sevenyears-old experimental plantations. The blocks were prepared for the water flow to occur in each wood axis and they were dried up to the final moisture content of 12%. Free water (FWFR), bound water (BWFR) and total water (TWFR) flow rates were calculated. The relationship between loss of moisture content and time presented an exponential curve, especially in the radial and tangential wood axes. Water flow in the three wood directions presented higher FWFR than TWFR (which was higher than BWFR). Free water flow was ~10 times higher than adsorbed water flow, considering values for moisture content between ~80% to ~12%. Free water movement in the longitudinal direction of the wood was ~2 times greater than in the radial axis and ~3 times greater than in the tangential axis. Bound water movement in the longitudinal direction of the wood was ~2 times greater than in the transverse direction. Bound water flow in the radial axis of the wood was statistically equal to the one in the tangential axis. The results indicate that the intensity of free and bound water flows changes according to the direction of Corymbia citriodora wood.

2022, Maderas. Ciencia y tecnología

Turkish hazel (Corylus colurna) lumber with a nominal thickness of 5 cm from the Kastamonu region, Turkey, was dried through conventional kiln drying using two different programs, a nonprotective drying schedule and a protective drying schedule. The goal of the study was to obtain a kiln schedule that would maintain wood quality and also save drying time until a final moisture content of 8 ± 2% was reached. The intensity of warping (twisting, bowing, cupping, crooking), superficial, internal, and end checks, residual stresses, drying rate, and moisture gradient of the dried woods were measured, and the results were evaluated according to the classification of the European Drying Group. The results showed a more homogeneous moisture profile, fewer occurrences of superficial checks, and an absence of internal checks when using the protective drying schedule due to low warping values compared with those for the non-protective drying schedule. From the point of view of energy efficiency, by saving 60 h of drying time, the non-protective schedule reduced electricity by 960 KWh and was therefore more profitable by $105,60 in this trial. Therefore, it seems that the protective drying schedule should be recommended as the optimum program for drying Turkish hazel lumber from the Kastamonu region at the commercial scale.

2022, Archives of Applied Science Research

The effect of density variation on the mechanical p roperties of Borassus aethiopum was assessed. Five trees were selected from the transitional zone in Ghana.“Wood” samples were collected from the three distinct zon e of the tree: the dermal zone, sub-dermal zone, and the cen tral at 15%, 30%, 45%, 60%, 75% and 90% of the tree merchantable height. One-half of the boards were us ed in the green state and the other half air dried for the dry tests. Mechanical strength test specimens and Densi ty were prepared and tested in accordance with the British Standard BS 373:1957.The mean basic density and [de nsity at 12%MC]for each of the zones in Kg/m 3 were 636.0 [793.3], 476.4 [579.1], and 251.2 [293.9] respectiv ely. The mean strength values in N/mm 2 in the ‘green’ [and dry] conditions for the dermal zone, sub-dermal zone, an d central zone were carried on Modulus of Rupture, Modulus of Elasticity, Compression parallel to the grain, Shea r parallel to the grain: 8.53 [11.64], 5.36 [7.7...

2022, BioResources

Changes were evaluated in cell wall components, hygroscopicity, and thermodynamic properties of Pinus sylvestris L. wood that had been in contact with salt (NaCl) for 300 years in a former saltworks storehouse in Gerri de la Sal (Lérida, Spain), comparing it with recently felled wood (new wood) of the same species. The wood in contact with salt (salt-covered wood) had higher equilibrium moisture content values except in the first interval of the adsorption isotherm, probably because of mechanical blocking of polar sites by salt crystals. The high fibre saturation point values of this wood are caused by the salt dissolved in water above water activity of about 0.75. More energy is invested in the desorption process, and the values are higher in the salt-covered wood.

2022

Water is one of the most significant factors for the durability of wood. A common solution is to use a coating to protect and maintain low water content. However, little knowledge exists how the underlying wood substrate affects the water sorption of coated wood. Therefore, the liquid water absorption of coated and uncoated Norway spruce heartwood and sapwood with a variety of densities was measured by letting the panels float freely in the water. The effect of one year weathering of the coatings was also included. Coated heartwood and sapwood had no difference in water absorption in opposite to uncoated spruce. The influence of heartwood and sapwood seemed to have limited impact when a coating hindered the presence of free water. Wood density had a positive effect on the absorption of coated wood, i.e. low absorption for low-density samples, in opposite to uncoated samples. Low-density characteristic also contributed to a lower increase of water absorption after weather degradation, for samples with water-borne coatings. Natural weathering enhanced the effect of wood characteristics on coated samples, likely by an increase of coating permeability.

2022

In order to assess the moisture content of wood chips on an industrial scale, readily applicable techniques are required. Thus, near infrared (NIR) spectroscopy was used to estimate moisture in wood chips by means of partial least squares regressions. NIR spectra were obtained in spectrometer with an integrating sphere and optical fiber probe, on the longitudinal and transverse surface of Eucalyptus wood chips. The specimens had their masses and NIR spectra measured in 10 steps during drying from saturated to anhydrous condition. Principal Component Analysis was performed to explore the effect of moisture of wood chip on NIR signatures. The values of moisture content of chips were associated with the respective NIR spectra by Partial Least Squares Regression (PLS-R) and Partial Least Squares Discriminant Analysis (PLS-DA) to estimate the moisture content of wood chips and its moisture classes, respectively. Model developed from spectra recorded on the longitudinal face by the integrating sphere method presented statistics slightly better (R²cv = 0,96; RMSEcv = 7,15 %) than model based on optical fiber probe (R²cv = 0,90; RMSEcv = 11,86 %). This study suggests that for calibration of robust predictive model for estimating moisture content in chips the spectra should be recorded on the longitudinal surface of wood using the integrating sphere acquisition method.

2022

En el presente estudio se investigaron las relaciones entre la velocidad de la onda acústica obtenida en árboles en pie (V ÁRBOL), y la obtenida en trozas (V TROZA), con distintas características de la madera, en árboles de Eucalyptus nitens con dimensiones aserrables, provenientes de una plantación de 18 años de edad, crecida en la región del Biobío, Chile. Se seleccionaron 9 árboles aleatoriamente. En cada árbol seleccionado se determinó la V ÁRBOL en las exposiciones cardinales Norte, Sur, Este y Oeste del fuste. La V TROZA se midió en trozas de 2,4 m de largo, centradas en longitud; a la altura fija de 2 m y al 33 %, 66 % y 100 % de la altura comercial del árbol. Para cada troza se obtuvo el contenido de humedad verde (CHv), la densidad verde (Dv), la densidad básica (DB), el módulo de elasticidad dinámico (MOEd), el indicador de la tensión de crecimiento (GSI), el módulo de elasticidad en tensión (Et) y las tensiones de crecimiento longitudinales (σ L). No hubo correlaciones significativas entre la V ÁRBOL y las distintas características examinadas en la madera (CHv, Dv, DB, GSI, Et y σ L). La velocidad de la onda acústica en trozas (V TROZA), cambió significativamente con la posición de la troza en el fuste, aumentando en dirección base-ápice. La V TROZA se correlacionó significativamente con distintos parámetros de calidad de la madera; ésta variable podría ser utilizada para clasificar trozas con un mayor módulo de elasticidad en tensión (Et), un menor contenido de humedad verde (CHv), y una menor densidad verde (Dv).

2022

The aim of this study was to know the variation profile of the specific energy consumption required to cut woods with varying densities and moisture contents. Therefore, peripheral cuts were performed in the longitudinal direction of the grain with numerical control controlled by Computational Numerical Command in woods of different densities, established at different drying stages. An energy analyzer, capable of calculate the specific energy consumed during the wood processing, was used to measure the energy information. The results indicated that the higher the wood density, the greater the positive influence of the moisture content on the specific cutting energy. In the anhydrous condition, the higher the wood density, the higher the cutting energy. With increased moisture content, less cutting power was required during the wood processing. Therefore, it was possible to conclude that during the milling type mechanical processing of wood, moisture content has a great influence on the specific cutting energy consumption.

2022

Near infrared spectroscopy is non-invasive and may be applied as a rapid and cost effective technique for assessment of quality parameters of timber. Near infrared spectra of Tectona grandis (teak) wood samples were collected before measuring physical (density, equilibrium moisture content) and strength (flexural and compressive) properties using conventional methods. Partial least squares regression was used to develop calibration models between measured wood properties and near infrared data. The best near infrared spectra pre-processing methods differed by property. Linear calibration models with high R², low error and high ratio of performance to deviation values were observed from partial least squares analysis for different wood properties. These linear models may be applied for rapid and precise estimation of the properties examined in testing and evaluation procedures for commercially valuable teak wood.

2022

2022, Wood and fiber Science

An ultrasonic defect detection system for radiata pine lumber based on 0.5 Mhz sound transmission through wood was tested. The feasibility of detecting knots, grain deviation, and growth ring angle with this system was investigated as well. The knot material, area of knot influence, and growth ring angle were significantly correlated to wave velocity. The ultrasonic scanning showed good agreement with visual prediction.

2022, Biodiversitas Journal of Biological Diversity

Jabon (Neolamarckia cadamba (Roxb) Bosser) is a potential tree species for the development of plantation forests and community forests to supply timber demands. Information on the growth characteristics and wood properties of N. cadamba is important for the present and future development, yet. Those data is not available. This study aimed to assess the variations on growth (height, diameter), pilodyn (Pilodyn®) penetration, and physical properties of wood from core sample; and characterize the wood properties of 12 N. cadamba provenances at Parung Panjang, Bogor. The assessment of growth characteristics, pilodyn penetration, and physical properties of wood from core sample was carried out through census (1030 trees) on all provenance (using non-destructive method). The wood properties analysis was carried out using destructive method to one sample for each of the 12 N. cadamba provenances. Growth characteristics observed were the height (numerical scale pole), diameter (calipers), and pilodyn penetration. Meanwhile, the wood properties consisted of wood density, specific gravity, moisture content, fiber length (light microscope), MFA (x-ray diffraction), MOE, and MOR. The results showed that the correlation between the height and moisture content with pilodyn penetration was weak and positive, while the correlation between diameter, wood density, and specific gravity was weak and negative. The result of non-destructive test showed that Gowa provenance is superior. The results of destructive tests to investigate the wood properties of the twelve provenances showed that Batu Licin provenance is superior in terms of specific gravity and MOE, while Gowa provenance is superior in terms of MOR and fiber length. The results of the wood properties (i.e. density, specific gravity, moisture content, MOE, MOR, MFA, and fiber length) of the 12 N. cadamba provenances showed that the woods can be potentially used as non-structural materials only.

2022, IARJSET

Timber is a renewable resource and preferred as building and construction material due to physical, mechanical, and has an aesthetically performance. However, timber varies due to its own property and proposes. The quality of the timber has a strong influence on the quality and value of timber products. Therefore, this study will be conducted to learn about mechanical strength properties of Terbulan (Endospermum diadenum sp.) fast-growing timber according to BS 373: 1957 Methods of Testing Small Clear Specimens of Timber. Instead of strength property, this study will be determined the suitable utilization of Terbulan timber for the construction industry. The test will be conducted on both conditions which are green and air-dry condition. Generally, Terbulan species is a fast-growing timber in Sarawak. From the point of view, the strength properties parameters such as basic density, modulus of rupture (MOR), modulus of elasticity (MOE) and compressive strength of Terbulan timber will be reviewed to determine the effectiveness of the species in the construction field. As a result of the analysis, it is found that Terbulan timber at the air-dry condition for MOR, MOE and compression parallel to grain reported with 84.17 N/mm², 10217.79 N/mm² and 28.94 N/mm² respectively. Terbulan is categorized in light hardwood timber and conclusion, related products are confined at the beginning it is a steel and concrete replacement that is mostly used in structure such as light construction, furniture and joinery.

2022

This study aimed to evaluate the modulus of elasticity of heat-treated wood subjected to decaying in field environment, by employing the ultrasound technique. For this, wood of Eucalyptus grandis and Pinus taeda from a TWBrazil plantation were used. From each species were selected five trees, which were then unfolded in boards that were dried and heat-treated at the temperatures of 140 and 160 oC. Afterwards, 75 specimens were obtained for each species, which were then exposed to the weather elements during 200 days and evaluated every 40 days, in the completely randomized design with a double factorial arrangement for the heat treatment and exposure time. In this period were collected data of the fungal decay potential in the site, and apparent specific gravity and dynamic modulus of elasticity (DMoE) from the wood samples. We verified the fungal decay potential increase with the exposure time, which also caused a reduction of the apparent specific gravity and DMoE in all treatment...

2022, Maderas. Ciencia y tecnología

In this paper result of working quality of Melia dubia is reported after testing them under six major wood working operations namely-planing, sanding, turning, shaping, boring and mortising based on Indian Standard IS 8292. The wood performed extremely well under planing. In shaping, the performance was good enough. Though all the other operations yielded poor results, the composite rating factor which is an overall performance indicator was 35 % more than that of Tectona grandis. The ease of working is only 93 % compared to teak. The working quality index which was based on the composite rating factor and ease of working worked out to 107 taking Tectona grandis as 100 mainly because of the high performance under planing and shaping and good performance under sanding.

2021

In an effort to provide a forum for researchers, the fiberbased materials. For example, early research on international NDT/NDE research community sponsors a NDT/NDE technologies for wood products focused on series of technical symposia for the exchange of technical methods for assessing the performance characteristics of information. These symposia are scheduled on a biannual structural lumber in North America. The NDT techniques, basis at locations throughout the world. equipment, and evaluation procedures that resulted from The International Nondestructive Testing and those efforts are now in widespread use. Currently, world Evaluation of Wood Symposium Series was initiated by wide research and development efforts are underway to Washington State University and the USDA Forest Products examine the potential use of a wide range of NDT technolo Laboratory (FPL). The first symposium was held at FPL in gies for evaluating wood and woodbased materials—from the fall of 1963, with p...

2021, Maderas. Ciencia y tecnología

This paper analyzes the usability of different dynamic moduli of elasticity and wood density for the prediction of mechanical properties-static modulus of elasticity and modulus of rupture-in samples with grain deflection from the longitudinal direction. Five tropical hardwoods (Afzelia bipindensis, Intsia bijuga, Millettia laurentii, Astronium graveolens and Microberlinia brazzavillensis) with different grain characteristics were used for this purpose. The fiber deflection was caused by the presence of interlocked grain or the working process. The three nondestructive techniques used in this study-longitudinal and flexural resonance method and ultrasound method-provided higher values of modulus of elasticity than the static bending test, but close correlation was observed between these variables. The weakest correlation was found for the ultrasound method which is probably caused by its measuring mechanism. The prediction of the modulus of rupture is less accurate when the dynamic modulus of elasticity is compared with the static modulus of elasticity; on the other hand, it was still good in comparison with the density model, which is inapplicable when grain deflection occurs in wood. In the wood of Zebrano where the interlocked grain was strongly developed, almost all of the correlation coefficients showed the lowest values and the prediction of modulus of rupture by nondestructive techniques was unsatisfactory.

2021

This paper analyzes the usability of different dynamic moduli of elasticity and wood density for the prediction of mechanical properties – static modulus of elasticity and modulus of rupture – in samples with grain deflection from the longitudinal direction. Five tropical hardwoods (Afzelia bipindensis, Intsia bijuga, Millettia laurentii, Astronium graveolens and Microberlinia brazzavillensis) with different grain characteristics were used for this purpose. The fiber deflection was caused by the presence of interlocked grain or the working process. The three nondestructive techniques used in this study – longitudinal and flexural resonance method and ultrasound method – provided higher values of modulus of elasticity than the static bending test, but close correlation was observed between these variables. The weakest correlation was found for the ultrasound method which is probably caused by its measuring mechanism. The prediction of the modulus of rupture is less accurate when the ...

2021, Maderas. Ciencia y tecnología

Juvenile Neolamarckia cadamba or kelempayan tree has been harvested from forest plantation and converted into sawn timber. Some basic properties of timber such as physical and mechanical were determined from different parts of the tree namely lower, center and upper. The physical properties were evaluated. The mechanical properties were conducted using small test clear specimens. The results indicated that the physical and mechanical properties of the lower portion of the trunk were significantly superior compared to the upper portion of the trunk. The investigation revealed that the wood be able to use as a substitute material of the furniture components after some modification undertaken on its properties.

2021, Maderas. Ciencia y tecnología

2021

Juvenile Neolamarckia cadamba or kelempayan tree has been harvested from forest plantation and converted into sawn timber. Some basic properties of timber such as physical and mechanical were determined from different parts of the tree namely lower, center and upper. The physical properties were evaluated based on MS 837:2006, BS EN 13183-1:2002 and ISO 3131:1975 (E). The mechanical properties were conducted using small test clear specimens following BS 373:1957. The results indicated that the physical and mechanical properties of the lower portion of the trunk were significantly superior compared to the upper portion of the trunk. The investigation revealed that the wood be able to use as a substitute material of the furniture components after some modification undertaken on its properties.

2021, Materials Science

2021, Materials Research

The permeability of Brazilian Eucalyptus grandis and Eucalyptus citriodora wood was measured in a custom build gas analysis chamber in order to determine which species could be successfully treated with preservatives. Liquid permeability was tested using an emulsion of Neen oil and a control of distillated water. Air was used to test the gas phase permeability. For both Eucalyptus grandis and Eucalyptus citriodora, the longitudinal permeability of gas was shown to be about twice as great as the liquid phase permeability. No radial permeability was observed for either wood. The permeability of air and water through the sapwood of Eucalyptus grandis was greater than that through the sapwood of Eucalyptus citriodora. The permeability of neen oil preservative through the sapwood of Eucalyptus grandis was also greater than through the sapwood of E. Citradora, but the difference was not statistically significant. Scanning Electron Microscopy images showed that the distribution and obstruction in the vessels could be correlated with observed permeability properties. Irrespective of the causes of differences in permeability between the species, the fluid phase flux through the sapwood of both species was significant, indicating that both Eucalyptus grandis and Eucalyptus citriodora could be successfully treated with wood preservative.

2021, BioResources

The overall aim of the research was to better understand the influence of raw material characteristics on the quality of decorative veneer, to identify phenotypes of oak and sessile oak valuable for veneer use, and to promote quality in relationship with sustainable development of Romania's forests. This paper describes specific aspects regarding wood defects and quality conditions imposed on raw materials for veneer slicing. The experiments focused on identifying and analyzing defects in oak veneer found in six regions from Romania. Taking into account the dimensional and quality requirements, and obtaining a sufficient quantity of decorative oak veneer, Pareto diagrams corresponding to each region were created. The Pareto analysis allowed for a hierarchy of main defects and also enabled adequate decision-making for improving the quality of the studied products in accordance with specific international standards. Also, by knowing the types of defects, decisions can be made to conserve natural resources and to utilize wood resources by sustainable reuse of waste.

2021, BioResources

2021, MATEC Web of Conferences

The paper presents the study of the strength parameters of wood samples from the retaining structure, working for about 60 years in an aggressive sea water environment. Samples from the variable water level zone and situated in the watered ground were tested. Non-destructive examinations were performed using the following methods: the stress wave technique and the ultrasonic wave technique. The results presented below can lead to the conclusion that both methods: the stress wave by Fakopp Microsecond Timer device and the ultrasonic wave by Sylvatest Trio correspond with each other and result in similar outcomes. However, in order to obtain more detailed and comprehensive information on the elements properties, more research should be conducted.

2021, Journal on Processing and Energy in Agriculture

In this paper, a faster and easier way, in comparison with classical methods, to determine the equilibrium moisture content in food materials is shown. The equilibrium moisture content is determined only experimentally, with determination of sorption isotherms. However, the key issue that is a condition for application of certain experimental method for determining of sorption isotherms is the reliability of experimental data obtained for equilibrium moisture content, as well as the time required to determine specific sorption isotherm. Despite numerous advantages of the static gravimetric method, the long time to achieve equilibrium moisture content of the sample is its main drawback and reason why the researchers use other techniques and methods. Out of these reasons came the idea to apply relatively fast and simple method to determine equilibrium moisture content in food materials, based on the values of average material temperature change obtained from experiments including convective drying kinetics. Furthermore, the resulting temperature response from the conducted experiments can be successfully used to determine unknown parameters in the models for calculation of equilibrium moisture content, by applying of inverse approach method that is an essential tool in modeling of heat and mass transfer processes for different food materials.

2021, Maderas. Ciencia y tecnología

Growth in world demand for wood implies a search for new fast growing species with silvicultural potential, and in this scenario for native species such as Paricá. Thus, the objective of this study was determining the physical and mechanical wood properties of the Schizolobium amazonicum species (known as Paricá in Brazil). Trees were collected from commercial plantations located in the north of Brazil with ages of 5, 7, 9 and 11 years. Four logs from trees of each age in the longitudinal direction of the trees were obtained, and later a diametrical plank of each log was taken to manufacture the specimens which were used to evaluate some physical and mechanical properties of the wood. The basic density of Paricá was reduced in the basetop direction and no difference between the radial positions was observed, while the average basic density of this wood was characterized as low. The region close to the bark showed less longitudinal contraction and also greater homogeneity of this property along the trunk, while for tangential contraction the smallest variation was found in the region near the pith. Paricá wood contraction was characterized as low. Age influenced most of the mechanical properties, where logs from the base had the highest values of mechanical strength.

2021, Journal of Civil Engineering, Science and Technology

Aras had been selected and tested in small clear specimens. Sampling of test specimens are made from three sections of the tree bole namely from bottom, middle, and top parts. This paper looks into the information of strength properties from three sections of sampled. The strength properties test required are the modulus of rupture, modulus of elasticity and compression stress parallel to grain. Meanwhile, the physical properties' test referred to moisture content and basic density. The testing conducted in two different conditions of the trees, which were referred to green and air-dry condition. It was found that the average mean values for modulus of rupture, modulus of elasticity and compressive stress parallel to grain tested at green condition were 47.52N/mm2, 6358.56N/mm2 and 22.42N/mm2 respectively meanwhile at air-dry condition were 70.49N/mm2, 8217.64N/mm2 and 34.07N/mm2 respectively. Meanwhile, the average mean values for moisture content at green condition were 83.34...

2021, Maderas. Ciencia y tecnología

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2021, Holz als Roh- und Werkstoff

The results of visual grading according to the Spanish (UNE 56544 2003) and German standards (DIN 4074 2003) for a sample of more than 200 sawn timber pieces of Scots pine from Germany are shown in this paper. The cross sections of the pieces were 40 × 180, 60 × 120, 60 × 180, 60 × 240, and 80 × 180 mm 2. The aim of this work is to compare the grading performance of both standards and to discover which criteria are the most relevant for determining the subsequent grading process. According to the results the Spanish standard has a lower grading performance than the German one, except for the highest strength class (C30) for which it is practically the same. A new procedure for the assessment of knot size is proposed with the aim of including it in the Spanish standard, giving better grading performance and making it easier to apply.