ABSTRACT Silver birch is a common European hardwood species possessing stiff and strong material properties. The mechanical properties of birch timber under compression loads are, however, not well defined as the influence of growth characteristics have largely been disregarded in experimental investigations. To address this, the present study investigated the effect of growth characteristics on the

The effect of the radial force applied by a ring debarker tip to frozen black spruce logs, obtained at three positions on the stem, was studied. A one-arm ring-debarker prototype was developed, which controlled the radial force, rake angle, and cutting and feed speeds. The experiment consisted of debarking logs using three different levels of radial force. The rake angle (80°), tip overlap (20%), and

(2020). Protecting wood infrastructure and mass timber buildings. Wood Material Science & Engineering. Ahead of Print.

Timber has been a versatile material for centuries. During the start of the Railway Age in the nineteenth century it was in considerable demand, particularly for bridge building. Timber is still in service and widely used throughout the UK network. The resilience and favourable strength to weight ratio and its relative ease of fabrication make it an attractive material. Longitudinal wheeltimbers are

Aminoplastic particleboard adhesives are reactive, inexpensive and well established in industry. Even so, potential adhesive savings are of interest due to a number of reasons. Therefore, fibrillar cellulosic additives derived from sugar beet pulp and from wood pulp were examined with regard to beneficial effects on adhesive performance. Particleboards were prepared with, varying adhesive content and

Factors relevant to degradation are important in every wood application. For wood used in ground and water contact; well documented abiotic factors (or agents) include exposure to temperature and moisture linked to the physiological requirements of biotic degradation agents such as wood-decaying fungi and bacteria. Other biotic degradation agents such as subterranean insects and marine borers occur

This paper focuses on the FE analysis of the mechanical behavior of glued composite fiber-reinforced polymer (FRP) rods into glulam timber, using a 3D-continuum damage mechanics. The application of FRP to the glulam timber beams, despite the fact of limited investigations to date, offers an interesting and economic solution for strengthening in timber construction. In particular, the use of glued-in

Wood properties, including Young’s modulus, differ among clones in Larix kaempferi; however, available information is still limited on among-clonal variations of lumber qualities in L. kaempferi. The objectives of this study were to clarify the clonal variations in lumber quality and to identify the effects of juvenile wood on lumber quality in L. kaempferi. A total of 21 logs of 2.5 m in length were

In this study, the fuzzy analytic hierarchy process was employed to prioritize some factors affecting the surface roughness of wood and wood-based materials in CNC machining. Within the model, four main factors and eighteen subfactors were defined. After constructing the hierarchical structure, the factors were analyzed through experts’ opinions. The results demonstrated that wood properties and machining

Wood is a highly optimised lightweight material showing excellent mechanical properties in the fibre direction. However, strength and stiffness are low perpendicular to grain. Due to knots, stem taper and spiral grain, the wood material includes local and global fibre deviations. Mechanical disintegration of logs into veneers and sawn timber is more or less ignoring the orientation of the natural wood

This study found that the substitution of 6% unbleached cellulose nanofibers (LCNF) into pMDI allowed for a reduction in density of 0.09 and 0.08 g/cm3 for equivalent performance in modulus of elasticity and modulus of rupture respectively; while, all other properties except internal bond were maintained. For panels made above 0.60 g/cm3, it was found that blows would consistently occur due to additional

This study exhibits the tuneable rubberwood with the actively controlled properties. Various amounts of polymethyl methacrylate (PMMA) were introduced into rubberwood tissues under the allowed environment. The embedded PMMA resulted to weight gaining up to about 60% and caused an increase in the density from 650 (for untreated rubberwood) to 1060 kg/m3 (for fully impregnated one). Additionally, scanning

ABSTRACT The purpose of this research is to develop a method for estimating the spatially and temporally resolved moisture content of thermally modified Scots pine (Pinus sylvestris) using remote sensing. Hyperspectral time series imaging in the NIR wavelength region (953–2516 nm) was used to gather information about the absorbance of eight thermally modified pine samples each minute as they dried

The objective of this work is to analyze the dry wood anatomical microstructure of Eucalyptus nitens, from an eight-year commercial plantation, by computed microtomography. 3D images with a voxel size of 5003 nm3 were acquired to study the tissue in areas without vessels. Quantitative and qualitative data of fibers, parenchyma, and pits were obtained. Permeability was estimated by numerical simulations

The paper investigates the addition of Nano-Al2O3 powder (alumina, Average Particle Size: 20 nm) on the characteristics of the Medium Density Fibreboards (MDF) made by the forest fibers. Some important physical, mechanical and quasi-static properties of the panels were measured according to the standard test methods and apparatus. Different percentages of alumina powder (0, 1, 2, and 3 weight percentage

Moisture is one of the most important wood properties because its variation directly influences the material strength and density. Thus, the aim of this study was to develop near infrared (NIR) spectroscopic models in order to estimate the moisture content in wood specimens. Moreover, predictive models built from NIR signatures recorded by different acquisition methods and on wood surfaces were compared

Wood is a biological material that is readily degraded by bacteria, fungi, and insects, as a result, enormous economic losses are incurred annually. The potentials of perishable wood species would be dependent on their treatability to increase their service life. This study reports on the treatability of wood by testing the hydraulic conductances as estimated by Hagen Poiseuille equation on four perishable

The potential of addition of calcium lignosulfonate as an eco-friendly additive with a phenol-formaldehyde (PF) resin, at different ratios, to produce medium-density fibreboards (MDF) with acceptable properties, was investigated in this work. The fibreboards were fabricated in the laboratory with low PF resin percentage (3%, 4%, 5%), while the addition levels of calcium lignosulfonate varied from 5%

Wood is by far the best structural material in terms of environmental impact. This superiority can be improved if the longevity of the commodity is extended by reducing the decay susceptibility of the heartwood not typically treatable using pressure methods. Traditionally, heartwood decay has been managed by remedial treatments, or simply by accepting the short service life and the required product

Crossarms are heavy timbers used to support electrical lines on utility poles. The requirements for crossarm material are fairly strict especially with respect to limitations on the presence of knots, which represent a gap or hole in the timber and also result in grain deviations that can affect properties. The strict grading rules can sometimes result in shortages of acceptable material. The potential

The structural integrity of wood–polymer composites (WPC) has not been fully investigated, which can be attributed to a lack of applicable test procedures. In this study, wood–polypropylene composites were assessed by High-Energy Multiple Impact (HEMI) testing. The acquired composites were based on wood particles from various sources and different wood fibre contents, respectively. With respect to

The complexity of Ceiba plywood damage makes prediction of onset and propagation of delamination an unavoidable problem. The aim of this work is to establish an onset criterion resulting from numerical modeling and a delamination propagation law from a series of experimental tests. Several tests have been put in place to evaluate the fracture toughness in mode I, mode II and mixed mode I+II. Numerical

ABSTRACT Thermal-hydro-mechanical (THM) densification treatments were performed on Populus spp. (poplar), Picea abies (spruce), and Fagus sylvatica (beech). Prior to THM treatment, a low-molecular weight resin was impregnated into the wood structure. Densification results, mechanical characteristics (modulus of elasticity, rupture, and hardness), and set-recovery were assessed. All wood species were

Finger-joint is a technological process that uses small-dimension and low-quality lumber to obtain high-quality structural wood products. Curing time of an adhesive consists one of the most important factors on the final performance of finger-jointed wood. In this study, finger-jointed black pine (Pinus nigra L.) specimens were prepared to investigate the effect of finger length and adhesive type on

The objective of this study was to evaluate some mechanical properties of OSB/3 after one to ten cycles of soaking and oven/drying (accelerated aging). The modulus of rupture (MOR), modulus of elasticity (MOE), found by 3-point bending and screw withdrawal load (SWL), were determined in dry and wet conditions in the face and back surface, and in the cutting edge. The specimens were soaked for 24 hours

This paper derives analytical predictions for notched cross-laminated timber (CLT) plate delamination using fracture mechanics for crack propagation from the notch root. The analysis accounts for both CLT heterogeneity and residual stresses caused by seasonal variations in temperature and humidity. The accuracy of predictions coupled with shear corrections, was confirmed by comparison to finite element

Mass timber represents a range of composite materials, including glued- or nail-laminated timber, cross-laminated timber, laminated veneer lumber, and mass plywood panels that are increasingly used to construct multi-story structures. The potential of these wood materials has energized the architectural and engineering communities as they seek less energy-intensive building materials. However, performance

Plasters are traditional surface finish materials in timber buildings. Today, the lack of fire performance data and design guidelines place such ecological materials at a disadvantage since plaster is not considered as a fire protection material for timber. This study aims to provide an up-to-date overview of performed fire tests accompanied by investigations on thermal properties of selected ready-mix

This paper deals with the experimental study devoted to cyclic compressive loading of three tropical species (Aucoumea Klaineana Pierre (AKP), Milicia Excelsa (ME) and Pterocarpus Soyauxii ( PS)) at different moisture content (MC) levels. According to the French requirement, NF EN 408, 90 samples are taken from these three species. The experimental campaign consists of static tests concerning 15 samples

This paper exploits the hygroscopic properties of wood and its passive response to fluctuation of relative humidity to develop a framework for programmable actuation in adaptive building façade design. This responsive shape shifting mechanism is specifically employed for the embedded actuation of dynamic shading configurations. Utilizing the hygroscopic properties of wood in adaptive shading devices

Sufficient dry-out capacity of the constructional moisture is important for solid wood structure wall assemblies, especially with a non-ventilated façade system. The objective of this study was to create a validated simulation model of a Massiv-Holz-Mauer (MHM) panel external wall with ETICS (External Thermal Insulation Composite Systems) based on the field measurements. Field measurements were carried

The importance of renewable and environmentally acceptable materials in the construction industry is increasing. Wood is one of the most important construction materials and its use in building applications has further expanded in recent decades, mainly due to the development of modern composites, firstly glue lam, OSB (Oriented Strand Board), LVL (Laminated Veneer Lumber) and a considerable breakthrough

The objective of this study is to evaluate the effect of wood and panel density on the properties of lightweight strand boards (SB). For this purpose, we compared lightweight SBs made of low-density kiri wood (Paulownia tomentosa), medium-density pine wood (Pinus sylvestris) and high-density beech wood (Fagus sylvatica). Single-layer non-oriented SBs were manufactured with target densities of 300 and

This study is related to drying of wood chips as a preconditioning step for wood pellet production. This article presents experimental data which are important in designing an industrial drying process: initial moisture content, bulk density, bulk porosity and desorption isotherm. Five wood species from the boreal forest have been investigated and two initial hydric states were considered, i.e. green

This research focuses on exploring commercial heat treatment on western hemlock product quality for potentially new applications and markets for this abundant Pacific Northwest coast softwood species. In this regard, flatsawn and quartersawn kiln-dried hemlock boards were subjected to the ThermoWood® process in a commercial unit at three temperatures, i.e. 170°C, 212°C, 230°C and for 2 h. Samples were

Because of the species similarity and the need to differentiate wood of the Myrtaceae family, this study aimed to evaluate the potential of near-infrared spectroscopy for discrimination of wood and charcoal from Campomanesia xanthocarpa Berg, Eugenia pyriformis Cambess., Myrcia retorta Cambess. and Plinia peruviana (Poir.) Govaerts, native of the Araucaria Forest. For each evaluated species, three

Contact-free digital image analysis was performed of the radial shrinkage of fresh, fully saturated small spruce wood beams. An experimental test set-up was developed to ensure constant distance from the charge-coupled device camera to the sample surface as well as constant climate and light conditions during the whole experiment. Dimensional changes were observed immediately after the drying process

(2019). Correction. Wood Material Science & Engineering. Ahead of Print.

In the Nordic countries, trees are typically bucked into logs using harvesters that measure only a two-dimensional diameter profile of the stem. Because the value of a log can vary significantly depending on its shape and internal defects, bucking decisions can in principle be improved by optical scanning of the three-dimensional stem shape, and detection of knots and other features inside the stem

Multi material mix is a promising approach to reduce weight and the carbon footprint in automotive engineering at competitive costs. As a result, automotive industry is getting more venturous, exploring and applying other materials than metals and plastics – e.g. fibre reinforced plastics (FRPs). In this context, engineered wood products (EWPs) and wood composites should be considered: Wood composites

This study investigates the influence of wood densities on moduli of rupture and elasticity, internal bond strength, surface soundness and density profiles of light and medium-density three-layered particleboards (PB). Therefore, particles of low and high-density wood species in three-layered PB were combined. Different combinations of beech (Fagus sylvatica L.) as high-density wood species and kiri

This study investigated the feasibility of substituting core layer strands of randomly oriented strand boards (OSB) with waste wood particles with respect to CSA 0437–Series 93 Standards on OSB and Waferboard requirements. Standard core layer strands have been substituted with four different levels (0, 25, 50 and 100%) of waste wood particles. Several mechanical properties of the OSB have been tested

While collared saws are no longer widely used in North America for primary breakdown of logs to boards, these are common in most of European sawmills. In North America, guided spline circular saws are used for sawing of boards of varying dimensions. This paper presents a stability analysis of spinning disk, an idealized representation of circular saw, for collared and splined arbor saws, when subjected

Wollastonite is an abundant mineral containing silicon, calcium and oxygen that has been shown to improve the properties of wood-based panels. Camel thorn (Alhagi maurorum) is a weed growing across much of Central Asia, and has relatively few commercial uses. The effects of addition of nano-wollastonite (NW) and camel-thorn chips on fire resistance of medium-density fiberboard (MDF) were assessed.

ABSTRACT Detailed planning for housing development is the responsibility of the respective municipalities in Sweden. Further, an ambition to develop sustainable building solutions based on wood is combined with each municipality’s building requirements, which increases complexity in the public process. Public actions leading to increased construction of wooden multi-family houses are important for

An improvement in energy performance for existing buildings is needed to fulfil EU energy policy. The efficient way to accomplish the idea of nearly-zero energy buildings (nZEB) is to apply the integrated design process and application of prefabricated insulation elements paired with the expertise of hygrothermal performance. In the current study, the commission of design and construction with emphasis

WPC boards were produced from recycled low-density polyethylene (rLDPE) and wood from three different invasive species found in the Western Cape, South Africa with the aim of using them as ceiling boards in low-cost housing projects. The study determined differences between two different types of rLDPE and the tree species, as well as tree composition with regards to physical and mechanical board properties

Sitka spruce wood specimens were heated at 120°C and different relative humidity during heating (RHh) levels for 2–7 days and their equilibrium moisture contents (EMCs) were measured at 25°C and 11–97% relative humidity (RH) before and after the removal of the water-soluble extractives. By heating at 80% RHh or less, a longer heating at higher RHh resulted in a greater reduction in the EMC; further

In this research, a sandwich panel with particleboard as surface layers and rigid polyurethane (PU) foam as core layers (foam-core particleboard) was produced with a one-step in situ foaming process. The effects of hydrofluorocarbon concentration as the blowing agent (BA) on the foam features and physical and mechanical properties of the produced panels were investigated. Typical micrograph of the

The purpose of this paper is to provide a better understanding of the behaviour of self-perforating dowels made of high-strength steel in CLT. The strength and stiffness of the connection is experimentally investigated and discussed, as are the influencing parameters. The results show the influence of the rope effect and drill tip on the load-carrying capacity of a connection with threaded dowels.

Increasing concern about the rapid proliferation of fungi attacking stands of radiata pine in the north of the Iberian Peninsula has led to a search for alternative conifer species that would be able to replace the affected trees. In this context one of the candidate species is the Japanese larch, a species that has not been structurally characterised within Spanish standards. This study describes

ABSTRACT The durability of wood depends on its in-use environmental conditions. The aim of this study was to estimate the effects associated with macro climate and detail design as well as their interdependence. A numerical moisture model and two different decay prediction models were utilized for assessing the decay risk of a horizontal member and a joint exposed at 300 sites scattered across Europe

This paper aimed to investigate the temperature dependence of thermal conductivity of heat-treated rubberwood (HTR). Rubberwood specimens were thermally treated at 180°C with three different durations of 15, 25 and 35 h, respectively. Thermal conductivity values of HTR at various mean temperature ranges were then examined. That of untreated rubberwood (UTR) was also measured as a comparison. The result

This paper presented the quality of the treated surface, which is most often followed by roughness representing micro-geometric irregularities of the treated surface. The processing influence parameters behaviour of on the roughness of the treated wood surface was considered, where the results of measurements of the average deviation of the roughness profile of the surface (Ra) of beech and maple wood

ABSTRACT Joints in timber structures are particularly vulnerable to degradation due to their tendency to trap moisture. The mechanisms involved, and their effect on the moisture conditions of wood, are here investigated numerically. The horizontal member of a rail and post-type configuration is modelled numerically by a two-dimensional diffusion model with material properties for Norway spruce. Contact

Veneer checking is a common enough occurrence in woodworking. It appears as cracks in the veneer and generally following the grain. Their appearance and the variation of their depth and frequencies have tremendous impact on their utilization. Finding a means of identifying and characterizing the veneer checks is an important ongoing challenge. An automated device, named SMOF, was developed in LABOMAP

This study deals with the influence of electron beam irradiation (EBI) on the wettability of Norway spruce surface samples. To evaluate this possible effect in detail, the changes in chemistry and wood structure were analysed using the methods of IR spectroscopy and Scanning Electron Microscopy (SEM). The surface wettability was determined by the contact angle measurement method. The results of infrared

The quality of finished wood products depends on the quality of its coating layer. An important indicator for evaluating the quality is Adherence of the paint on the wood surface. The purpose of this research was to analyze the effect of wood surface roughness and the viscosity of acrylic paints (pure acrylic and acrylic copolymer) to the wettability and Adherence for long and short rotation teaks

Eucalyptus nitens specimens were thermally modified under open and closed systems. The anatomical characteristics from selected modifications that presented similar mass losses were investigated by analyzing images taken from scanning electron microscopy, transmission light microscopy, and X-ray micro-computed tomography. Wood cell wall thickness, fiber, and lumen area were measured and compared to

This article describes and explains a relatively unknown thermal wood modification process in pressurised unsaturated steam. Compared to other processes for the thermal conversion of wood, this hygrothermolytic (HGT) process has the unique feature of an additional independent and continuous process variable, enabling the full control of the water activity throughout the entire heating cycle. This process