Engineering › Building and Construction

Wood Treatment and Properties

Works Count: 37674

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This cluster of papers covers a wide range of topics related to advancements in wood science and technology, including wood chemistry, FTIR analysis, heat treatment effects, timber construction, microstructure analysis, wood modification techniques, mechanical properties of wood, thermal modification processes, fungal decay of wood, and nanomechanical studies.

Keywords

Wood Chemistry; FTIR Analysis; Heat Treatment; Timber Construction; Microstructure; Wood Modification; Mechanical Properties; Thermal Modification; Fungal Decay; Nanomechanics

Study of chemical modifications and fungi degradation of thermally modified wood using DRIFT spectroscopy

2003-04-02

Josef Weiland , René Guyonnet

Handbook of Wood Chemistry and Wood Composites

2005-02-18

Roger M. Rowell

Preface Wood and Society, Christopher D. Risbrudt STRUCTURE AND CHEMISTRY Structure and Function of Wood, Alex C. Wiedenhoeft and Regis B. Miller Cell Wall Chemistry, Roger M. Rowell, Roger Pettersen, … Preface Wood and Society, Christopher D. Risbrudt STRUCTURE AND CHEMISTRY Structure and Function of Wood, Alex C. Wiedenhoeft and Regis B. Miller Cell Wall Chemistry, Roger M. Rowell, Roger Pettersen, James S. Han, Jeffrey S. Rowell, and Mandla A. Tshabalala PROPERTIES Moisture Properties, Roger M. Rowell Biological Properties, Rebecca E. Ibach Thermal Properties, Roger M. Rowell and Susan L. LeVan-Green Weathering of Wood, R. Sam Williams Surface Characterization, Mandla A. Tshabalala WOOD COMPOSITES Wood Adhesion and Adhesives, Charles R. Frihart Wood Composites, Lars Bergland and Roger M. Rowell Chemistry of Wood Strength, Jerrold E. Winandy and Roger M. Rowell Fiber Webs, Roger M. Rowell, James S. Han and Von Y. Byrd Wood Thermoplastic Composites, Daniel F. Caulfield, Craig Clemons, Rodney E. Jacobson, and Roger M. Rowell PROPERTY IMPROVEMENTS Chemical Modification of Wood, Roger M. Rowell Lumen Modifications, Rebecca E. Ibach and W. Dale Ellis Plasma Treatment of Wood, Ferencz S. Denes, L. Emilio Cruz-Barba, and Sorin Manolache

Chemical changes in hydrothermal treated wood: FTIR analysis of combined hydrothermal and dry heat-treated wood

2005-02-17

Bôke Tjeerdsma , Holger Militz

Strength properties of thermally modified softwoods and its relation to polymeric structural wood constituents

2007-01-01

Michiel J. Boonstra , Joris Van Acker , Bôke Tjeerdsma +1 more

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Wood

1983-12-31

Dietrich Fengel , G. Wegener

The anatomy and chemistry of wood are described in detail, and with extensive reference to the literature, under the following headings: Introduction; Structure and ultrastructure; Chemical composition and analysis of … The anatomy and chemistry of wood are described in detail, and with extensive reference to the literature, under the following headings: Introduction; Structure and ultrastructure; Chemical composition and analysis of wood; Cellulose; Polyoses (hemicelluloses); Lignin; Extractives; Distribution of the components within the wood cell wall; Constituents of bark; Reactions in acidic medium; Reactions in alkaline medium; Influence of temperature; Degradation by light and ionizing rays; Microbial and enzymatic degradation; Aging and fossilization; Pulping processes; Derivatives of cellulose; and Utilization of wood and wood components for chemicals and energy. -- AATA

A mathematical model of mould growth on wooden material

1999-12-07

Antti Hukka , Hannu Viitanen

Chemical changes during the production of thermo-treated beech wood

2007-06-12

Elisabeth Windeisen , Claudia Strobel , G. Wegener

Characterisation of thermally modified hard- and softwoods by C CPMAS NMR

2004-09-10

Hanne Wikberg , Sirkka Liisa Maunu

Spectral Characterization of Eucalyptus Wood

2007-11-01

Carmen–Mihaela Popescu , Maria‐Cristina Popescu , G. Singurel +3 more

The main difficulties in wood and pulp analyses arise principally from their numerous components with different chemical structures. Therefore, the basic problem in a specific analytical procedure may be the … The main difficulties in wood and pulp analyses arise principally from their numerous components with different chemical structures. Therefore, the basic problem in a specific analytical procedure may be the selective separation of the main carbohydrate-derived components from lignin due to their chemical association and structural coexistence. The processing of the wood determines some structural modification in its components depending on the type of wood and the applied procedure. Fourier transform infrared (FT-IR) spectrometry and X-ray diffraction have been applied to analyze Eucalyptus g. wood chips and unbleached and chloritebleached pulp. The differences between samples have been established by examination of the spectra of the fractions obtained by successive extraction (acetone extractives, acetone free extractive samples, hemicelluloses, and lignins) by evaluating the derivative spectra, band deconvolution, etc. The energy and the hydrogen bonding distance have been evaluated. The relationship between spectral characteristics and sample composition has been established, as well as the variation of the degree of crystallinity after pulping and bleaching. The integral absorption and lignin/carbohydrate ratios calculated from FT-IR spectra of the IR bands assigned to different bending or stretching in lignin groups are stronger in the spectrum of eucalyptus chips than those from brown stock (BS) pulp spectra because of the smaller total amount of lignin in the latter. FT-IR spectra clearly show that after chlorite bleaching the structure of the wood components is partially modified or removed. Along with FT-IR data, the X-ray results confirmed the low content of lignin in the pulp samples by increasing the calculated values of the crystalline parameters. It was concluded that FT-IR spectroscopy can be used as a quick method to differentiate Eucalyptus globulus samples.

Cyclic Analysis of Wood Shear Walls

2001-04-01

Bryan Folz , André Filiatrault

A simple numerical model to predict the load-displacement response and energy dissipation characteristics of wood shear walls under general quasi-static cyclic loading is presented. In this model the shear wall … A simple numerical model to predict the load-displacement response and energy dissipation characteristics of wood shear walls under general quasi-static cyclic loading is presented. In this model the shear wall is composed of three structural components: rigid framing members, linear elastic sheathing panels, and nonlinear sheathing-to-framing connectors. The hysteretic model for the sheathing-to-framing connector takes account of pinching behavior and strength and stiffness degradation under cyclic loading. A robust displacement control solution strategy is utilized to predict the wall response under general cyclic loading protocols. The shear wall model has been incorporated into the computer program CASHEW (Cyclic Analysis of SHEar Walls). The predictive capabilities of this program are compared with monotonic and cyclic tests of full-scale wood shear walls. It is shown that this model can accurately predict the load-displacement response and energy dissipation characteristic of wood shear walls under general cyclic loading. As an application of the CASHEW program, a procedure is presented for calibrating a single degree-of-freedom system to predict the complete nonlinear dynamic response of shear walls under seismic loading.

Investigation of wood wettability changes during heat treatment on the basis of chemical analysis

2005-03-22

Mohammed Hakkou , Mathieu Pétrissans , André Zoulalian +1 more

Study of the effect of photo-irradiation on the surface chemistry of wood

2005-03-31

Krishna K. Pandey

Qualitative and quantitative analysis of wood samples by Fourier transform infrared spectroscopy and multivariate analysis

2010-06-05

Huilun Chen , C. Ferrari , Marco Angiuli +3 more

Micromechanical understanding of the cell-wall structure

2004-09-01

Lennart Salmén

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Effect of High Temperature on the Change in Color, Dimensional Stability and Mechanical Properties of Spruce Wood

2003-08-20

Pavlo Bekhta , Peter Niemz

Summary In this study the effect of high temperature on mechanical properties, dimensional stability and color of spruce was investigated. Wood specimens conditioned at different relative humidities (50, 65, 80 … Summary In this study the effect of high temperature on mechanical properties, dimensional stability and color of spruce was investigated. Wood specimens conditioned at different relative humidities (50, 65, 80 and 95%) were subjected to heat treatment at 200°C for 2, 4, 8, 10 and 24 h and at 100, 150 and 200°C for 24 h. Color changes were measured in the Minolta Croma-Meter CR-300 color system. Bending strength and modulus of elasticity were determined according to DIN 52186. The results show that heat treatment mainly resulted in a darkening of wood tissues, improvement of the dimensional stability of wood and reduction of its mechanical properties. The darkening accelerated generally when treatment temperature exceeded approximately 200°C. Most of the darkening occurred within the first 4 h of exposure. For the specimens heated to high temperatures, the average decrease in bending strength was about 44–50%, while modulus of elasticity was reduced by only 4–9%. We found that treatment time and temperature were more important than relative humidity regarding the color responses. Strong correlations between total color difference and both modulus of elasticity and bending strength were found. Thus, the color parameters can be estimated quantitatively and used as a prediction of wood strength.

Relaxation behaviour of the amorphous components of wood

1987-02-01

Stephen S. Kelley , Timothy G. Rials , Wolfgang G. Glasser

Photodegradation and photostabilisation of wood – the state of the art

2005-01-07

Béatrice George , Ed Suttie , André Merlin +1 more

Application of Fracture Mechanics to Anisotropic Plates

1967-12-01

Edward M. Wu

The conditions necessary for the application of fracture mechanics to anisotropic materials were examined and verified experimentally on orthotropic plates. It was observed that crack extension, by opening and forward … The conditions necessary for the application of fracture mechanics to anisotropic materials were examined and verified experimentally on orthotropic plates. It was observed that crack extension, by opening and forward sliding, occurred independently and the associated stress-intensity factors at the state of incipient fracture are material constants. An empirical relation (k1/k1c) + (k2/k2c)2 = 1 was found to be a fracture criterion for both balsa wood and fiber-glass-reinforced plastic plates, inferring the existence of a general law of fracture for orthotropic materials.

The Chemical Composition of Wood

1984-05-05

Roger C. Pettersen

ADVERTISEMENT RETURN TO BOOKPREVChapterNEXTThe Chemical Composition of WoodROGER C. PETTERSENROGER C. PETTERSENU.S. Department of Agriculture, Forest Service, Forest Products Laboratory, Madison, WI 53705More by ROGER C. PETTERSENDOI: 10.1021/ba-1984-0207.ch002Publication Date (Print):May … ADVERTISEMENT RETURN TO BOOKPREVChapterNEXTThe Chemical Composition of WoodROGER C. PETTERSENROGER C. PETTERSENU.S. Department of Agriculture, Forest Service, Forest Products Laboratory, Madison, WI 53705More by ROGER C. PETTERSENDOI: 10.1021/ba-1984-0207.ch002Publication Date (Print):May 5, 1984Publication History Published online22 July 2009Published inprint 5 May 1984RIGHTS & PERMISSIONSThe Chemistry of Solid WoodChapter 2pp 57-126Advances in ChemistryVol. 207ISBN13: 9780841207967eISBN: 9780841223899 Copyright © 1984 American Chemical SocietyChapter Views715Citations350LEARN ABOUT THESE METRICSChapter Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (6 MB) SUBJECTS:Wood Get e-Alerts

Investigations of the reasons for fungal durability of heat-treated beech wood

2005-07-13

Mohammed Hakkou , Mathieu Pétrissans , Philippe Gérardin +1 more

Evaluation of morphological and chemical aspects of different wood species by spectroscopy and thermal methods

2011-01-06

Maria‐Cristina Popescu , Carmen–Mihaela Popescu , Gabriela Lisă +1 more

Influence of steam heating on the properties of pine (Pinus pinaster) and eucalypt (Eucalyptus globulus) wood

2006-08-14

Bruno Esteves , António Vélez Marques , Idalina Domingos +1 more

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Durability of heat-treated wood

2002-02-01

D. Pascal Kamdem , A. Pizzi , Alain Jermannaud

State of the Art on Timber-Concrete Composite Structures: Literature Review

2010-12-03

David Yeoh , Massimo Fragiacomo , Mary De Franceschi +1 more

This paper presents a survey on the state-of-the-art of timber-concrete composite research in the past and recent years. The most important literature references were carefully selected and reviewed to provide … This paper presents a survey on the state-of-the-art of timber-concrete composite research in the past and recent years. The most important literature references were carefully selected and reviewed to provide an overview and some depth in the development of this construction technique. After highlighting the advantages of the composite system, the standards and design methods currently available are presented. An extensive description of the connection systems developed around the world is also provided. The experimental and numerical investigations performed on connections and beams in both the short- and long-term (at collapse and under sustained load, respectively) are discussed at length in the paper. Other aspects covered are prefabrication, the influence of concrete properties, fatigue tests, fire resistance, vibrations, and acoustics.

Mechanical and chemical behavior of spruce wood modified by heat

2005-08-30

Sibel Yıldız , Engin Derya Gezer , Ümit Cafer Yıldız

Microfibril Angle: Measurement, Variation and Relationships – A Review

2008-01-01

Lloyd Donaldson

Microfibril angle (MFA) is perhaps the easiest ultrastructural variable to measure for wood cell walls, and certainly the only such variable that has been measured on a large scale. Because … Microfibril angle (MFA) is perhaps the easiest ultrastructural variable to measure for wood cell walls, and certainly the only such variable that has been measured on a large scale. Because cellulose is crystalline, the MFA of the S 2 layer can be measured by X-ray diffraction. Automated X-ray scanning devices such as SilviScan have produced large datasets for a range of timber species using increment core samples. In conifers, microfibril angles are large in the juvenile wood and small in the mature wood. MFA is larger at the base of the tree for a given ring number from the pith, and decreases with height, increasing slightly at the top tree. In hardwoods, similar patterns occur, but with much less variation and much smaller microfibril angles in juvenile wood. MFA has significant heritability, but is also influenced by environmental factors as shown by its increased values in compression wood, decreased values in tension wood and, often, increased values following nutrient or water supplementation. Adjacent individual tracheids can show moderate differences in MFA that may be related to tracheid length, but not to lumen diameter or cell wall thickness. While there has been strong interest in the MFA of the S 2 layer, which dominates the axial stiffness properties of tracheids and fibres, there has been little attention given to the microfibril angles of S 1 and S 3 layers, which may influence collapse resistance and other lateral properties. Such investigations have been limited by the much greater difficulty of measuring angles for these wall layers. MFA, in combination with basic density, shows a strong relationship to longitudinal modulus of elasticity, and to longitudinal shrinkage, which are the main reasons for interest in this cell wall property in conifers. In hardwoods, MFA is of more interest in relation to growth stress and shrinkage behaviour.

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A method for flexural reinforcement of old wood beams with CFRP materials

2004-06-18

Antonio Borri , Marco Corradi , Andrea Grazini

Chemical analysis of heat treated softwoods

2006-01-09

Michiel J. Boonstra , Bôke Tjeerdsma

Wood modification by heat treatment: A review

2008-12-04

Bruno Esteves , Helena Pereira

Wood heat treatment has increased significantly in the last few years and is still growing as an industrial process to improve some wood properties. The first studies on heat treatment … Wood heat treatment has increased significantly in the last few years and is still growing as an industrial process to improve some wood properties. The first studies on heat treatment investigated mainly equilibrium moisture, dimensional stability, durability and mechanical properties. Mass loss, wettability, wood color, and chemical transformations have been subsequently extensively studied, while recent works focus on quality control, modeling, and study the reasons for the improvements. This review explains the recent interest on the heat treatment of wood and synthesizes the major publications on this subject on wood properties, chemical changes, wood uses, and quality control.

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Effect of thermal treatment on the chemical composition and mechanical properties of birch and aspen

2008-03-15

Duygu Kocaefe , Sándor Poncsák , Yaman Boluk

The high temperature treatment of wood is one of the alternatives to chemical treatment. During this process, the wood is heated to higher temperatures than those of conventional drying. The … The high temperature treatment of wood is one of the alternatives to chemical treatment. During this process, the wood is heated to higher temperatures than those of conventional drying. The wood structure changes due to decomposition of hemicelluloses, ramification of lignin, and crystallization of cellulose. The wood becomes less hygroscopic. These changes improve the dimensional stability of wood, increase its resistance to micro-organisms, darken its color, and modify its hardness. However, wood also might loose some of its elasticity. Consequently, the heat treatment conditions have to be optimized. Therefore, it is important to understand the transformation of the chemical structure of wood caused by the treatment. In this study, the modification of the surface composition of the wood was followed with Fourier transform infrared spectroscopy (FTIR) and inverse gas chromatography (IGC) under different experimental conditions. The effect of maximum treatment temperatures on the chemical composition of Canadian birch and aspen as well as the correlations between their chemical transformation and different mechanical properties are presented. FTIR analysis results showed that the heat treatment affected the chemical composition of birch more compared to that of aspen. The results of IGC tests illustrated that the surfaces of the aspen and birch became more basic with heat treatment. The mechanical properties were affected by degradation of hemicellulose, ramification of lignin and cellulose crystallization.

Cellulose microfibril angle in the cell wall of wood fibres

2004-05-01

John Barnett , Victoria A. Bonham

ABSTRACT The term microfibril angle (MFA) in wood science refers to the angle between the direction of the helical windings of cellulose microfibrils in the secondary cell wall of fibres … ABSTRACT The term microfibril angle (MFA) in wood science refers to the angle between the direction of the helical windings of cellulose microfibrils in the secondary cell wall of fibres and tracheids and the long axis of cell. Technologically, it is usually applied to the orientation of cellulose microfibrils in the S2 layer that makes up the greatest proportion of the wall thickness, since it is this which most affects the physical properties of wood. This review describes the organisation of the cellulose component of the secondary wall of fibres and tracheids and the various methods that have been used for the measurement of MFA. It considers the variation of MFA within the tree and the biological reason for the large differences found between juvenile (or core) wood and mature (or outer) wood. The ability of the tree to vary MFA in response to environmental stress, particularly in reaction wood, is also described. Differences in MFA have a profound effect on the properties of wood, in particular its stiffness. The large MFA in juvenile wood confers low stiffness and gives the sapling the flexibility it needs to survive high winds without breaking. It also means, however, that timber containing a high proportion of juvenile wood is unsuitable for use as high‐grade structural timber. This fact has taken on increasing importance in view of the trend in forestry towards short rotation cropping of fast grown species. These trees at harvest may contain 50% or more of timber with low stiffness and therefore, low economic value. Although they are presently grown mainly for pulp, pressure for increased timber production means that ways will be sought to improve the quality of their timber by reducing juvenile wood MFA. The mechanism by which the orientation of microfibril deposition is controlled is still a matter of debate. However, the application of molecular techniques is likely to enable modification of this process. The extent to which these techniques should be used to improve timber quality by reducing MFA in juvenile wood is, however, uncertain, since care must be taken to avoid compromising the safety of the tree.

SOFIE project – 3D shaking table test on a seven‐storey full‐scale cross‐laminated timber building

2013-05-23

Ario Ceccotti , Carmen Sandhaas , Minoru Okabe +3 more

SUMMARY Multi‐storey buildings made of cross‐laminated timber panels (X‐lam) are becoming a stronger and economically valid alternative in Europe compared with traditional masonry or concrete buildings. During the design process … SUMMARY Multi‐storey buildings made of cross‐laminated timber panels (X‐lam) are becoming a stronger and economically valid alternative in Europe compared with traditional masonry or concrete buildings. During the design process of these multi‐storey buildings, also their earthquake behaviour has to be addressed, especially in seismic‐prone areas such as Italy. However, limited knowledge on the seismic performance is available for this innovative massive timber product. On the basis of extensive testing series comprising monotonic and reversed cyclic tests on X‐lam panels, a pseudodynamic test on a one‐storey X‐lam specimen and 1D shaking table tests on a full‐scale three‐storey specimen, a full‐scale seven‐storey building was designed according to the European seismic standard Eurocode 8 and subjected to earthquake loading on a 3D shaking table. The building was designed with a preliminary action reduction factor of three that had been derived from the experimental results on the three‐storey building. The outcomes of this comprehensive research project called ‘SOFIE – Sistema Costruttivo Fiemme’ proved the suitability of multi‐storey X‐lam structures for earthquake‐prone regions. The buildings demonstrated self‐centring capabilities and high stiffness combined with sufficient ductility to avoid brittle failures. The tests provided useful information for the seismic design with force‐based methods as defined in Eurocode 8, that is, a preliminary experimentally based action reduction factor of three was confirmed. Valid, ductile joint assemblies were developed, and their importance for the energy dissipation in buildings with rigid X‐lam panels became evident. The seven‐storey building showed relatively high accelerations in the upper storeys, which could lead to secondary damage and which have to be addressed in future research. Copyright © 2013 John Wiley & Sons, Ltd.

A critical discussion of the physics of wood–water interactions

2012-10-14

Emil Tang Engelund , Lisbeth G. Thygesen , Staffan Svensson +1 more

Abstract This paper reviews recent findings on wood–water interaction and puts them into context of established knowledge in the field. Several new findings challenge prevalent theories and are critically discussed … Abstract This paper reviews recent findings on wood–water interaction and puts them into context of established knowledge in the field. Several new findings challenge prevalent theories and are critically discussed in an attempt to advance current knowledge and highlight gaps. The focus of this review is put on water in the broadest concept of wood products, that is, the living tree is not considered. Moreover, the review covers the basic wood–water relation, states and transitions. Secondary effects such as the ability of water to alter physical properties of wood are only discussed in cases where there is an influence on state and/or transition.

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Cross laminated timber (CLT): overview and development

2016-01-19

Reinhard Brandner , George Flatscher , Andreas Ringhofer +2 more

Chemistry of Weathering and Protection

1984-05-05

William C. Feist , David N.‐S. Hon

Wood exposed to the outdoors undergoes photodegradation and photooxidative degradation in the natural weathering process. UV light interacts with lignin to initiate discoloration and deterioration. Deterioration of wood in the … Wood exposed to the outdoors undergoes photodegradation and photooxidative degradation in the natural weathering process. UV light interacts with lignin to initiate discoloration and deterioration. Deterioration of wood in the natural weathering process involves a very complex, free radical reaction sequence. Light does not penetrate wood past 200 μm; therefore, degradation reactions are a surface phenomenon. The free radicals generated in wood by light rapidly interact with oxygen to produce hydroperoxides which in turn are easily decomposed to produce chromophoric groups. In this chapter the influence of outdoor weathering on the performance of wood and wood-based materials is discussed in detail. Macroscopic, microscopic, chemical, and physical changes are described. The mechanisms of weathering and methods of protection of exposed wood surfaces are summarized.

Effect of Moisture Content and Temperature on the Mechanical Properties of Wood: An Analysis of Immediate Effects

1982-01-01

C. C. Gerhards

Mechanical properties of wood increase as moisture content decreases below fiber saturation point, at least down to about 5% MC, and as temperature decreases. This report summarizes the relevant studies … Mechanical properties of wood increase as moisture content decreases below fiber saturation point, at least down to about 5% MC, and as temperature decreases. This report summarizes the relevant studies reported in the literature on the immediate effects of moisture content and temperature on several mechanical properties of clear wood. Recommendations are made for future research.

Wood modification technologies - a review

2017-12-01

Dick Sandberg , Andreja Kutnar , George I. Mantanis

The market for new durable products of modified wood has increased substantially during the last few years, especially in Europe. This increased interest depends partly on the restricted use of … The market for new durable products of modified wood has increased substantially during the last few years, especially in Europe. This increased interest depends partly on the restricted use of toxic preservatives due to increased environmental concern, as well as the need for reduced maintenance for wood products that are mainly for exterior use. Furthermore, as sustainability becomes a greater concern, the environmental impact of construction and interior materials should be included in planning by considering the entire life cycle and embodied energy of the materials used. As a result, wood modification has been implemented to improve the intrinsic properties of wood, widen the range of sawn timber applications, and acquire the form and functionality desired by engineers, without bringing environmental friendliness into question. The different wood modification processes are at various stages of development, and the challenges that must be overcome to expand to industrial applications differ amongst them. In this paper, three groups of wood modification processes are discussed and exemplified with modified wood products that have been newly introduced to the market: (i) chemical processing (acetylation, furfurylation, resin impregnation etc.); (ii) thermo-hydro processing (thermal treatment); and (iii) thermo-hydro-mechanical processing (surface densification). Building on these examples, the paper will discuss the environmental impact assessment of modification processes and further development needs.

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Wood modification by heat treatment: A review

2008-12-04

Bruno Esteves , Helena M. Pereira

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The Chemistry of Solid Wood

1984-05-05

Roger M. Rowell

Wood—a natural, cellular, composite material of botanical origin—possesses unique structural and chemical characteristics that render it desirable for a broad variety of end uses. The level of suitability for a … Wood—a natural, cellular, composite material of botanical origin—possesses unique structural and chemical characteristics that render it desirable for a broad variety of end uses. The level of suitability for a given end use (i.e., wood quality) is frequently determined by the wood's response to imposed physical and chemical treatments. However, in addition to these criteria, wood quality is also often based on the behavior of wood when subjected to the natural forces of the environment (e.g., weather, fire, and decay). All of these performance criteria are related either directly or indirectly to wood chemistry together with the wood's organizational architecture at the macroscopic and microscopic levels. This chapter reviews both of these structural domains, the development of wood characteristics in a growing tree, and why these characteristics can govern the behavior of wood under various treatment regimes. Emphasis is also given to the potential sources of wood variability, including wood type (softwood or hardwood), tree genus or species, and the variability present even within a single tree.

Transport Processes in Wood

1984-01-01

John F. Siau

ADHESIVE PENETRATION IN WOOD—A REVIEW

2007-09-27

Frederick A. Kamke , Jong N. Lee

Adhesive bond performance between wood elements is presumed to be significantly influenced by the degree of penetration of the adhesive into the porous network of interconnected cells. Research on the … Adhesive bond performance between wood elements is presumed to be significantly influenced by the degree of penetration of the adhesive into the porous network of interconnected cells. Research on the bondline performance has been conducted through microscopic examination and associated techniques in an effort to establish relationships with the bond performance. The purpose of this communication is to provide a technical review of research on adhesive penetration, and to promote the efficient use of adhesives in regard to cost and performance, particularly in reference to the manufacture of wood-based composites. Assessment techniques, influence on bond performance, and distinctive characteristics of common adhesives used for the wood-based composites industry were the main focus of this review. Variability between wood species, the wide variety of adhesive application and curing processes, and the many types of adhesive chemistries and formulations make sweeping generalities difficult. However, troubleshooting bonding problems and designing new adhesive systems and processes may be facilitated by understanding the fundamentals of adhesive penetration.

An efficient computational model for progressive failure analysis of cross-laminated timber panels

2025-06-24

Emilija Jočić , Marija Todorović , Ivan Glišović +1 more | Archive of Applied Mechanics

Kavak kaplamadan üretilen tabakalı kaplama kerestenin mekanik özellikleri üzerine rutubet içeriğinin etkisinin değerlendirilmesi

2025-06-24

Bilgehan Asena Şenay İlker , Bekir Cihad Bal | Mobilya ve Ahşap Malzeme Araştırmaları Dergisi

Özellikle son yıllarda meydana gelen depremlerden sonra, ahşap yapılara karşı ilgi artmıştır. Ancak, ahşap yapılarda yük taşıyan ahşap esaslı elemanların çürümeye, yangına ve rutubete karşı dayanımı bu ilgiyi etkilemektedir. Bu … Özellikle son yıllarda meydana gelen depremlerden sonra, ahşap yapılara karşı ilgi artmıştır. Ancak, ahşap yapılarda yük taşıyan ahşap esaslı elemanların çürümeye, yangına ve rutubete karşı dayanımı bu ilgiyi etkilemektedir. Bu çalışmada, kavak ağacından elde edilen soyma kaplama ile tabakalı kaplama kereste (TKK) üretilmiş ve malzemenin bazı mekanik özellikleri farklı rutubet içeriklerinde incelenmiştir. TKK üretiminde Fenol Formaldehit (FF) tutkalı kullanılmıştır. Üretilen malzeme 5 farklı rutubet içeriğine şartlandırılmıştır, ardından çeşitli mekanik testlere tabi tutulmuştur. Bu amaç için, üretilen malzemesinin bazı fiziksel özelikleri (tam kuru yoğunluk ve rutubet yüzdesi) ve mekanik özellikleri (Eğilme direnci, eğilmede elastikiyet modülü, eğilmede deformasyon, sertlik, vida tutma kapasitesi, çekme-makaslama direnci) belirlenmiştir. Yapılan testler sonunda elde edilen bulgulara göre; TKK’nın rutubet içeriği arttıkça, eğilme direnci, elastikiyet modülü, sertlik değeri ve vida tutma kapasitesi azalmış, buna karşı, eğilmede deformasyon değeri artış göstermiştir. Çekme-makaslama direnci testi ile rutubet içeriği arasında doğrusal bir ilişki tespit edilememiştir.

Evaluation of Timber Mechanical Properties Through Non-Destructive Testing: A Bibliometric Analysis

2025-06-23

Marwa Brougui , Krisztián Andor , Péter Szabó | Buildings

This study presents a comprehensive bibliometric analysis of research trends in evaluating the mechanical properties of timber structures, with a particular emphasis on the modulus of elasticity (MOE) assessed through … This study presents a comprehensive bibliometric analysis of research trends in evaluating the mechanical properties of timber structures, with a particular emphasis on the modulus of elasticity (MOE) assessed through non-destructive testing (NDT) methods, especially ultrasonic waves. Using VOSviewer software to analyze 129 Scopus-indexed publications, the analysis reveals a marked increase in research activity since the early 2000s and the formation of distinct thematic clusters. The keyword ’non-destructive examination’ consistently emerges as the dominant term, underscoring a sustained and focused scientific interest in this field. Despite this growth, significant gaps remain, notably the lack of standardized methodologies and limited application of ultrasonic NDT techniques for in-service timber structures. This underscores the urgent need for targeted research efforts, including integrating machine learning with ultrasonic analysis, developing standardized testing protocols, exploring hybrid diagnostic approaches, and extending ultrasonic methods to aged and recycled timber. Furthermore, advancing portable, in-situ ultrasonic systems is essential to enable real-time, field-based assessments. This study not only maps the current research landscape but also highlights strategic opportunities to improve the accuracy, reliability, and sustainability of timber mechanical property evaluations, thereby supporting the advancement of timber engineering.

Determination of Strength Improvements in the Acacia Hybrid Through the Combination of Age Groups at the Air-Dry Conditioning Stage

2025-06-23

Fanthy Moola Malek , Gaddafi Ismaili , Noor Azland Jainudin +7 more | Forests

Acacia hybrid is an important plantation species in Malaysia, but its use in structural applications is still limited due to the lack of comprehensive data on its engineering properties. This … Acacia hybrid is an important plantation species in Malaysia, but its use in structural applications is still limited due to the lack of comprehensive data on its engineering properties. This study evaluated the physical and mechanical properties of laminated or glulam Acacia hybrid timber in an air-dried condition for three age group combinations (7//10, 10//13, and 7//13 years old) to determine the optimal combination for structural applications. The results showed that the 10//13-year-old combination had the best mechanical performance, along with the highest basis density (0.7099 g/cm3), highest modulus of elasticity (MOE) (16,335.6 N/mm2), and highest parallel compressive strength (56.998 N/mm2), while the 7//10-year-old combination showed the highest moisture content (14.94%) and highest perpendicular compressive strength (8.9256 N/mm2). This study demonstrated that the combination of juvenile wood (7 years old) with mature wood (10 or 13 years old) increased strength by up to 43.06%, thus optimising the potential of Acacia hybrid in the construction industry. All combinations meet SG5 standards, with the 10//13-year-old combination recommended as the best choice for high-performance applications of glulam products.

Filling the gap: modelling sorption isotherms between hygroscopic and water-saturated conditions based on microscopic characterisation of softwood anatomy

2025-06-23

Maria Fredriksson , Emil Engelund Thybring , Ramūnas Digaitis +1 more | Cellulose

Abstract The relation between moisture content of a material and the ambient climate is described by sorption isotherms. Several models for prediction of sorption isotherms exist in the hygroscopic moisture … Abstract The relation between moisture content of a material and the ambient climate is described by sorption isotherms. Several models for prediction of sorption isotherms exist in the hygroscopic moisture range, but models of sorption isotherms in the over-hygroscopic range are less abundant. In wood, water can be present both in the solid cell wall and in the macro voids (e.g. cell lumina, pit chambers) in the wood structure. In the over-hygroscopic range, moisture uptake primarily occurs in the porous structure outside of the cell walls by capillary condensation. That is, condensation occurs at a certain partial pressure which depends on pore size and geometry. Since wood has an ordered structure and distinct geometries this link enables prediction of the relative humidity at which capillary condensation occurs in different macro voids. Here, this was explored by using a mathematical model for prediction of moisture sorption by capillary condensation in the macro void structures of softwoods. Both absorption and desorption isotherms were modelled, and sorption hysteresis was included by the ink-bottle effect. The model was based on wood anatomy data which was determined for softwood material based on quantitative wood anatomy. The modelling results were compared to experimental sorption data. In general, there was a reasonable agreement; two different theoretical criteria for emptying of cell lumina in desorption were tested and, in most cases, the experimental data were in between these two versions of the modelled desorption isotherms. The moisture content at saturation was, however, most often underestimated by the model.

Comparison of mass-timber and RC buildings in terms of seismic performance, LCA, and cost in Türkiye

2025-06-22

Ekrem Mutlu , Kadir C. Sener , Özgür Anıl | Bulletin of Earthquake Engineering

Abstract The two devastating earthquakes of 6 February 2023 in Kahramanmaraş, Türkiye, highlighted the poor seismic performance of many existing reinforced concrete (RC) buildings and created an urgent need for … Abstract The two devastating earthquakes of 6 February 2023 in Kahramanmaraş, Türkiye, highlighted the poor seismic performance of many existing reinforced concrete (RC) buildings and created an urgent need for rapid, large-scale reconstruction. This study evaluates the feasibility of using a modern mass-timber structural system as an alternative to conventional RC construction for mid-rise residential buildings in Turkish seismic regions. A seven-story residential building was designed in two forms – one with a standard RC shear-wall structure and one with an equivalent mass-timber (cross-laminated timber, CLT) structure – and compared their seismic performance, environmental impacts, and construction costs. Nonlinear static (pushover) and response spectrum analyses were conducted for both designs in accordance with applicable seismic design standards. A cradle-to-gate life-cycle assessment (LCA) was performed to quantify embodied carbon and energy, and a cost analysis was carried out using local 2023 material prices. The CLT building achieved adequate seismic performance, with fundamental periods about twice as long as the RC building and base shear forces roughly one-third as large. Although the CLT structure experienced larger lateral drifts, these remained within serviceable limits. In terms of sustainability, the mass-timber design showed dramatically lower environmental impacts – roughly an order of magnitude reduction in embodied carbon and energy – compared to the RC design. The primary trade-off was economic: due to current material pricing and supply constraints, the mass-timber building’s estimated construction cost was approximately 5–6 times higher than the RC building. Overall, the results indicate that mass-timber is a structurally viable and environmentally advantageous option for post-earthquake reconstruction of mid-rise buildings in Türkiye, provided that issues of cost and material supply can be addressed through future policy and market developments.

The Mechanical Properties of Laminated Veneer Products from Different Stands of Douglas Fir and Norway Spruce in Germany

2025-06-21

Tobias Krenn , Dirk Berthold , Nina Ritter +1 more | Forests

The relationship between silvicultural strategies, manifested in the thinning method and rotation age on sites with different water supply, and the mechanical properties of engineered wood products plywood and laminated … The relationship between silvicultural strategies, manifested in the thinning method and rotation age on sites with different water supply, and the mechanical properties of engineered wood products plywood and laminated veneer lumber has been analyzed. Sample logs from five German sites of Norway spruce (Picea abies (L.) Karst.) and Douglas fir (Pseudotsuga menziesii (M.) Franco) have been rotary-peeled and processed into boards with a phenol–resorcinol–formaldehyde adhesive to evaluate their performance under flexural, tensile, and compressive loads. Satisfactory coefficients of determination were reached for Norway spruce in regard to the silvicultural framework and the tree characteristics of slenderness and crown base height. Douglas fir products did not achieve comparable determination due to high variance within boards and stands but did achieve significantly better mechanical properties. Norway spruce was observed to be more responsive to thinning measures, while the effect of different thinning regimes was not evident for Douglas fir. The on-site evaluation of Douglas fir stands for veneer product quality based on silvicultural parameters and tree characteristics was shown to be inconclusive, with its naturally higher wood density being the decisive constant.

Enhanced particle swarm optimisation technique for parametrising the hysteresis response in timber dowel-type connections

2025-06-21

Hossein Daneshvar , Nastaran Cheshmehkaboodi , Brian Qi +1 more | Structures

Experimental investigation and probabilistic modelling of the load–displacement behaviour of steel-to-timber joints with self-tapping screws

2025-06-20

Dorotea Caprio , Robert Jockwer | Construction and Building Materials

Impact of moisture and NIR sensors on calibration transfer between predictive models of Eucalyptus grandis wood density

2025-06-20

Dayane Targino de Medeiros , Felipe Gomes Batista , Adriano Reis Prazeres Mascarenhas +2 more | Infrared Physics & Technology

Effects of conventional drying and superheated steam drying on the drying quality, deresination, physical, and mechanical properties of radiata pine heartwood and sapwood

2025-06-19

Fan Zhou , Xuan Fang , Yongdong Zhou +2 more | Drying Technology

Vibration performance of cross-laminated timber (CLT)-concrete composite floors considering the section thickness ratio between CLT panels and concrete slabs

2025-06-19

Yingwei Bao , Yu Han , Zhenbo Xu +3 more | Engineering Structures

Mode II fracture behavior of Norway spruce: CBBM and DIC analysis at small and structural scales

2025-06-19

Jiří Kunecký , Martin Hataj , Jan Jochman +3 more | Construction and Building Materials

Review of non-destructive testing for quality evaluation of in-service timber utility poles

2025-06-19

Nasim Bahrami , Himadri Rajput , Rahil Changotra +2 more | Structures

Experimental and Finite Element Study on Wooden Joints Strengthened by Detachable Steel Sleeves

2025-06-19

Jiajun Gao , Jianhua Shao , Yong Wang +5 more | Buildings

We designed detachable steel sleeves to reinforce wooden joints and improve their integrity under earthquake action and investigated their mechanical properties. Monotonic bending tests were performed on a half-tenon pure … We designed detachable steel sleeves to reinforce wooden joints and improve their integrity under earthquake action and investigated their mechanical properties. Monotonic bending tests were performed on a half-tenon pure wooden joint and a joint strengthened by a detachable steel sleeve. More obvious tenon pulling-out failure was observed in the pure wood joint; in comparison, only slight extrusion fracture of wooden beams and extrusion deformation of steel sleeves occurred in the wood joint reinforced by a detachable steel sleeve. Our test results showed that the initial rotational stiffness of the strengthened joint, JG1, was increased by 495.4% compared with that of the unstrengthened joint, JG0. The yield bending moment increased by 425.9%, and the ultimate bending moment increased by 627.5%, which indicated that the mechanical performance was significantly improved when the joint was reinforced by a detachable steel sleeve. Numerical simulations of different components were performed with finite element analysis software to analyze the mechanical performance of the reinforced joint. It was found that the stiffness and ultimate flexural performance of the joint could be increased by setting stiffeners on the steel sleeve and connecting the wooden column with self-tapping screws. The results of the tests were compared with those obtained through finite element analysis, and a high degree of accuracy was achieved, which could provide a theoretical basis for the reinforcement of timber structural buildings.

Study on hot-press drying process for the flatten-bamboo slice

2025-06-19

Zhixin Lin , Mengxue Shi , Huanrong Liu +3 more | Drying Technology

Investigating impact sound insulation in cross-laminated timber (CLT)-concrete composite floors with embedded mechanical fastening: Experimental analysis and statistical energy analysis

2025-06-18

Yingwei Bao , Kong Yue , Changlu Dai +4 more | Journal of Building Engineering

Assessment of Quality Parameters of Finger-Jointed Timber Products: A Review

2025-06-18

C. K. Muthumala , S. De Silva , P. L. A. G. Alwis +2 more | Bulletin of the Transilvania University of Brasov Series II Forestry • Wood Industry • Agricultural Food Engineering

Wood is a renewable natural resource used in diverse sectors. Wood processing operations generate a substantial quantity of residues which possess higher potential of alternative uses. Finger-jointing, a method which … Wood is a renewable natural resource used in diverse sectors. Wood processing operations generate a substantial quantity of residues which possess higher potential of alternative uses. Finger-jointing, a method which connects two small pieces of timber together, is identified as a sound technique to minimize wastage. In the present context, where deforestation continues to threaten the existing timber resources, the finger-joint technique has gained higher recognition as a viable tool for the sustainable utilization of wood. With the increasing demand and decreasing volume of high-grade timber material, finger-jointing has become an industry with great economic benefits, and finger-joint technology will boost the increased utilization of timber materials. The outcomes of this review paper will therefore improve the quality of finger-jointed products through the generated technical information and thereby enhance the finger-jointing industry in practice.

Performance of timber-concrete composite members: a Study on connectors and failure modes

2025-06-18

P. Ochoa , Siva Avudaiappan , Aitor Cendoya +5 more | Journal of the Indian Academy of Wood Science

Göknar ve karaçam tahtalarının TS 1265 standardına göre görsel mukavemet sınıflandırması

2025-06-18

Fatih Kurul | Anadolu Orman Araştırmaları Dergisi

Giriş ve hedefler Bu çalışmada; yerli türlerimizden olan Uludağ göknarı (Abies nordmanniana subsp. Bornmuelleriana) ve Anadolu karaçamı (Pinus nigra Arnold. subsp. pallasiana) kerestelerinden üretilmiş yapısal tahtaların TS 1265 standardına göre … Giriş ve hedefler Bu çalışmada; yerli türlerimizden olan Uludağ göknarı (Abies nordmanniana subsp. Bornmuelleriana) ve Anadolu karaçamı (Pinus nigra Arnold. subsp. pallasiana) kerestelerinden üretilmiş yapısal tahtaların TS 1265 standardına göre görsel mukavemet sınıflarını belirlemek ve benzer çalışmalar için altlık oluşturmak hedeflenmiştir. Yöntemler Öncelikle göknar ve karaçam yapısal tahtalar (toplam 356 adet) TS 1265 (2012) standartlarına göre görsel sınıflandırmaya tabi tutulmuştur. Sonrasında TS EN 408 (2014) standardına göre 4-noktalı eğilme test düzeneğinde global elastikiyet modülü ve eğilme direnci testleri yapılmıştır. Testlerden sonra her numuneden kusursuz parçalar kesilerek yoğunluk ve rutubet miktarları belirlenmiş ve TS EN 384 (2022) standardına göre gerekli tahvil işlemleri yapılmıştır. Sonrasında her iki tür için tüm görsel sınıflara karşılık gelen mukavemet sınıfları belirlenmiştir. Bulgular Geniş yüzeye paralel testlerde budak çapı oranı arttıkça yani sınıf kötüleştikçe ahşabın mekanik özelliklerinde ve mukavemet sınıflarında önemli azalmalar görülürken, yıllık halkaların yüzeye çıkış açısının istatistiksel olarak mekanik özellikleri etkilemediği saptanmıştır. Her bir görsel sınıf için karaçamda, göknara göre daha yüksek mekanik özellikler tespit edilmiştir. Sonuçlar Sonuç olarak, görsel mukavemet sınıflandırması için, göknar ve karaçamdan elde edilen 1.sınıf, 2.sınıf ve 3.sınıf yapısal tahtalar sırasıyla C27-C20-C14 ve C35-C22-C16 mukavemet sınıflarına atanmıştır. Elde edilen sonuçlara göre TS 1265 (2012) standardının yapısal tahtaların görsel mukavemet sınıflandırması için uygun olduğu söylenebilir.

Numerical analysis of heat and mass transfers during intermittent microwave drying of Eucalyptus globulus wood

2025-06-16

Bedjaoui Marwa , Soufien Azzouz , Salaheddine Azzouz +2 more | Drying Technology

A Comparative Study on the Effects of Heat Treatment on the Properties of Rubberwood Veneer

2025-06-16

Yayun Wu , He Sun , Zi You +4 more | Forests

Heat treatment is a widely employed method for modifying solid wood and has also been extended to veneer-type woods. Owing to the thinness and ease of handling of veneers, the … Heat treatment is a widely employed method for modifying solid wood and has also been extended to veneer-type woods. Owing to the thinness and ease of handling of veneers, the regulation of protective media in heat treatment has not been highly regarded by the industry and is scarcely reported in research. In light of this, in this paper, rubber wood (Hevea brasiliensis) veneer is taken as the research subject to investigate the influences of heat treatment with hot air (HTHA) and heat treatment with superheated steam (HTSS) at different temperatures on the chemical properties, longitudinal tensile strength, color values, hygroscopicity, thermal degradation performance and microstructure of the wood. The results show that heat treatment alters the chemical properties of wood. Both heat treatments reduce the content of hemicellulose and other components in the veneer, and the characteristic peak of lignin in HTSS is slightly enhanced. The crystallinity of the veneer slightly increases after heat treatment, and the increase in HTSS is greater than that in HTHA. Through scanning electron microscopy, it is observed that heat treatment can effectively remove starch granules in rubber wood veneer, with HTSS being superior to HTHA, and the removal effect increases with the rise in temperature. The longitudinal tensile strength of the veneer decreased by 0.69%, 3.87%, and 24.98% respectively at 135~155 °C HTHA, and by 3.25%, 7.00%, and 18.47% respectively at 135~155 °C HTSS. Both heat treatments reduced the lightness of the veneer and increased the chroma index. At 155 °C, the color difference value of the veneer treated by HTSS was smaller than that treated by HTHA. The effects of heat treatment on the moisture absorption performance of the veneer were different. The equilibrium moisture content of the veneer treated at 135 °C HTHA and 135~155 °C HTSS was lower than that of the untreated material, indicating an improvement in moisture absorption stability. The maximum moisture sorption hysteresis of untreated material is 3.39%. The maximum moisture sorption hysteresis of 135 °C HTHA is not much different from that of untreated material. The values of 145 °C and 155 °C HTHA increase by 8.85% and 9.14% respectively. The values of 135 °C, 145 °C, and 155 °C HTSS increase by 22.42%, 25.37%, and 19.47% respectively. The moisture absorption hysteresis of the veneer increases after heat treatment, and the effect of HTSS improvement is more significant. From the TG and DTG curves, it can be seen that the residual mass percentage of the veneer after heat treatment is higher than that of the untreated material. The residual mass percentage of HTHA at 135 °C, 145 °C, and 155 °C increased by 3.13%, 3.07%, and 2.06% respectively, and that of HTSS increased by 5.14%, 7.21%, and 6.08% respectively.

Assessment of Knot-Induced Degradation in Timber Beams: Probabilistic Modeling and Data-Driven Prediction of Load Capacity Loss

2025-06-15

Peixuan Wang , Guoming Liu , Fanrong Li +3 more | Buildings

Timber structural performance is significantly influenced by natural knots, which serve as critical indicators in ancient architectural heritage preservation and modern sustainable building design. However, existing studies lack a comprehensive … Timber structural performance is significantly influenced by natural knots, which serve as critical indicators in ancient architectural heritage preservation and modern sustainable building design. However, existing studies lack a comprehensive quantitative analysis of how the randomness of timber knot parameters relates to load-bearing capacity degradation. This study introduces a multiscale evaluation framework that integrates physical testing, probabilistic modeling, and data-driven techniques. Firstly, static tests on full-scale timber beams with artificially introduced knots reveal the failure mechanisms and load capacity reduction associated with knots in the tension zone. Subsequently, a three-dimensional Monte Carlo simulation, modeling random distributions of knot position and size, demonstrates that the midspan region is most sensitive to knot effects, with load capacity loss being more pronounced on the tension side than on the compression side. Finally, a predictive model based on a fully connected neural network is developed; feature analysis indicates that the longitudinal position of knots exerts a stronger nonlinear influence on load capacity than radial depth or diameter. The results establish a mapping between knot characteristics, stress field distortion, and ultimate load capacity, providing a theoretical basis for safety evaluation of historic timber structures and the design of defect-tolerant timber beams in modern engineering.

Flexural properties and treatability of wooden poles from Eucalyptus clonal hybrids grown in Tanzania

2025-06-15

Justine W. Alistides , R. C. Ishengoma , Fortunatus B. S. Makonda +2 more | Wood Material Science and Engineering

Fire-resistant performance and residual bearing capacity of Dou-Gong brackets in Chinese ancient wooden architecture treated with transparent fireproof coatings

2025-06-13

Xin Li , Miaotian Long , Long Yan +3 more | Construction and Building Materials

Isıl İşleme Tabi Tutulmuş Ahşap Malzemelerin Boyutsal Stabilitesi

2025-06-12

Vahit Eşener , Eylem D. Tomak | Ağaç ve Orman

Ahşabın boyutsal kararlılığı ve nem içeriği, onun nihai kullanımını etkileyen önemli fiziksel özelliklerdendir. Bu çalışmada, meşe (Quercus spp.), sarı kavak (Dalbergia decipularis), ayous (Triplochiton scleroxylon K. Schum), iroko (Milicia excelsa), … Ahşabın boyutsal kararlılığı ve nem içeriği, onun nihai kullanımını etkileyen önemli fiziksel özelliklerdendir. Bu çalışmada, meşe (Quercus spp.), sarı kavak (Dalbergia decipularis), ayous (Triplochiton scleroxylon K. Schum), iroko (Milicia excelsa), dişbudak (Fraxinus spp.) ve çam (Pinus sylvestris) türlerine ait keresteler endüstriyel bir ısıl işlem tesisinde 212°C’de termal modifikasyona tabi tutulmuştur. Termal modifiyeli ve termal modifiyesiz (kontrol) kerestelerden 20x20x30 mm boyutlarında örnekler kesilmiştir. Her grup için 10 adet örnek kullanılmıştır. Tam kuru ağırlık ve boyutları belirlenen örnekler, daha sonra suyun içerisinde 5 gün boyunca bekletilmiş ve süre sonunda tekrar tam kuru ağırlık ve boyutları alınmıştır. Bu döngü 2 kez tekrarlanmıştır. Deneyde örneklerin su alma oranı (%), su itici etkinliği (%), hacimsel genişleme katsayısı (%) ve boyutsal stabilitesi (%) hesaplanmıştır. Sonuç olarak, termal modifiyeli örneklerde kontrollerine kıyasla en az su alma oranı meşe ve ayous odununda görülmüştür. Su itici etkinlik açısından, çam ve sarı kavak örneklerde ısıl işlemin etkisi diğer odun türlerine kıyasla daha düşük tespit edilmiştir. Hacimsel genişleme katsayısı ise, ısıl işlemli dişbudak, çam, sarı kavak ve nispeten meşede, kontrollerine kıyasla önemli ölçüde düşük bulunmuştur. Test edilen 6 tür arasında en düşük boyutsal stabilite iroko odununda tespit edilmiştir.

Monitoring the long-term stability of classical guitar necks: evaluating the potential of European-grown wood species in musical instrument manufacturing

2025-06-12

Bingrui Chen , Pieter Goovaerts , Stijn Willen +6 more | Wood Science and Technology

Effect of pre-freezing treatments on the drying behavior of Eucalyptus platyphylla F. V. Muell

2025-06-11

Lin Yang , Shuang Li , Ying Han | Drying Technology

Testing of Concrete Beams Reinforced with Wood and Steel Bars Under Flexural Loads

2025-06-08

M. T. Mustafa , Amr Aly Gamal El Din , tarek abdelgalil | Deleted Journal

Enhancing rubberwood properties via sodium silicate modification: A study on mechanical and thermal stability

2025-06-06

Zi You , He Sun , Yayun Wu +4 more | BioResources

Rubberwood (RW), a commercially valuable timber species widely used for mid-to-high-end wood products in Yunnan, was modified through full-cell impregnation with sodium silicate (SS) solutions at varying concentrations (10 to … Rubberwood (RW), a commercially valuable timber species widely used for mid-to-high-end wood products in Yunnan, was modified through full-cell impregnation with sodium silicate (SS) solutions at varying concentrations (10 to 30%). The treatment significantly improved the wood’s performance, overcoming challenges such as achieving optimal impregnation while preserving its integrity. Comprehensive analysis indicated that a 20% sodium silicate solution provided the most effective modification. This optimal treatment increased compressive strength by 15% (78.8 MPa), increased modulus of elasticity by 35.7% (1900 MPa), and reduced water absorption by 13.3% (103.5%) compared to untreated samples. Microstructural analysis confirmed optimal impregnation at 20%, with Fourier Transform Infrared (FTIR) spectroscopy revealing Si-O-Si peaks and X-ray photoelectron spectroscopy (XPS) indicating the presence of silicon, confirming the successful penetration of sodium silicate and silica formation. Furthermore, X-ray diffraction (XRD) analysis indicated that there was no alteration in the position of the cellulose diffraction peaks, which demonstrated that the sodium silicate impregnation treatment did not destroy its crystalline structure. This modification enhanced the mechanical properties and thermal stability of rubberwood while providing an eco-friendly alternative to traditional chemical treatments. Sodium silicate, mildly toxic and abundant, offers a sustainable solution for improving wood quality in various applications.

Optimizing air velocity for energy-efficient and sustainable rubberwood drying kilns

2025-06-01

Suratsavadee K. Korkua , Choosak Rittiphet , Siraporn Sakphrom +3 more | Results in Engineering