Wood Panels Research Articles

Thermal decomposition and combustion of interior design materials

Research findings on the patterns of thermal decomposition and combustion are reported for widely used interior design materials. The experiments were conducted using a hardware and software system including a thermogravimetric analyzer (to record the characteristics of thermal decomposition), a gas analyzer (with H2, CH4, H2S, SO2, CO and CO2 sensors) and a high-speed camera (to record the characteristics of ignition and combustion). The temperature of the oxidizing medium ranged from 500 to 900°C to investigate the conditions of thermal decomposition initiation and sustained combustion. It was established that the highest concentrations of toxic emissions were typical of the combustion of polypropylene at a maximum temperature of the oxidizing medium (900°C). Wood showed the shortest ignition delay time and the longest duration of combustion. The experimental data were used for a physical problem statement and mathematical model of heat and mass transfer to explore the thermal decomposition and combustion of interior design materials in different rooms. A comparison of the experimental findings with the mathematical modeling results validates the developed model. The growth rates of carbon monoxide and carbon dioxide concentrations were determined for construction (wooden) and interior design (polymer) materials. The maximum concentrations of CO and CO2, and the minimum times taken to reach their threshold values corresponded to wood and polyvinyl chloride panels. This research provides a deeper insight into the thermal decomposition of a wide range of fuels and the formation of gaseous pyrolysis products of these fuels. The results obtained can be used to evaluate the toxicity of construction and interior design materials during compartment fires as well as to estimate the safe egress time and risks involved in the process. They can also serve as a database for the development and testing of mathematical models describing fire outbreaks and propagation in confined spaces.

Validation of the Physical and Mechanical Properties of Eucalyptus benthamii Maiden & Cambage Wood and Cross Laminated Timber Panels Using the Finite Element Method

Cross Laminated Timber (CLT) is a structurally complex panel that poses challenges in analysis due to the anisotropic nature of wood and the orthotropic characteristics of the composite. Numerical modeling using the Finite Element Method (FEM) offers a viable solution for analysis, particularly for addressing boundary value problems that are analytically challenging. Therefore, it is crucial to validate the experimental properties to ensure accurate results. The objective of this study was to validate the physical and mechanical properties for structural modeling using FEM, based on the characterization of Eucalyptus benthamii Maiden & Cambage wood and CLT panels. For wood characterization, the basic and apparent density were determined, and mechanical tests, including static bending, parallel-to-grain compression, and shear tests, were conducted. Utilizing the same batch of wood, three-layer CLT panels were manufactured and subjected to a non-destructive three-point bending test. This test was simulated in RFEM finite element software, employing Mindlin’s theory, and the displacements obtained were compared with the experimental method. The results from a Student’s t-test at a 5% significance level indicated no significant difference between the experimental and numerical methods, suggesting that the properties of the experimental E. benthamii CLT panel can be accurately represented by FEM.

Utilization of nanotalc modified adhesives in plywood panels

As an alternative for the partial replacement of synthetic adhesives are the modifications that occur still during their synthesis, to improve and adhere new properties. Among the possible materials used in nanoscale, talc is a mineral material of natural origin and a promising raw material due to its low cost, lightness, natural hydrophobicity. Due to the scarcity of studies with the insertion of nanotalc in adhesives, this study aimed to produce plywood panels bonded with phenol-formaldehyde adhesive nanomodified with talc to evaluate its physical-mechanical resistance when compared to conventional synthetic adhesives. To carry out this study, three Pinus oocarpa trees with 28 years of age were used. Different concentrations of talc were used in the formulation with the phenol-formaldehyde adhesive, being the treatments 0; 0,05; 1; 1,5 and 2 % of talc (mass/mass) in relation to the adhesive, with three panels per treatment, totaling 15 panels. The pressing time was 8 minutes with temperature of 160 ºC and pressure of 1 MPa. The physical-chemical characteristics of the lignocellulosic material and of the plywood panels were determined. The quality of the adhesive produced was demonstrated by its resistance to water absorption with the insertion of up to 2 % talc to the adhesive, reducing it considerably. From 1 % talc inserted, the plywood panels had their mechanical characteristics superior to those glued with pure phenol-formaldehyde adhesive. However, as the study is innovative in nature, further research should focus on the application and quality evaluation of other talc nanomodified adhesives on different types of wood panels.

Towards Sustainable Production: An Adaptive Intelligent Optimization Genetic Algorithm for Solid Wood Panel Manufacturing

Optimizing production processes to conserve resources and reduce waste has become crucial in pursuing sustainable manufacturing practices. The solid wood panel industry, marked by substantial raw materials and energy consumption, stands at the forefront of addressing this challenge. This research delves into production scheduling and equipment utilization inefficiencies, offering innovative solutions for the solid wood panel processing line aimed at achieving environmental sustainability and operational efficiency. The study is articulated through two main segments: (1) an exhaustive analysis and the development of a simulation system for the solid wood panel processing line, delineating all production elements and operational logic, furnished with a user-friendly simulation interface, and (2) a comprehensive evaluation and enhancement of various scheduling algorithms specific to the Flexible Job-Shop Scheduling Problem (FJSP) encountered in solid wood panel workshops. A significant leap forward is made with the introduction of the Adaptive Intelligent Optimization Genetic Algorithm (AIOGA), an evolved version of the standard Genetic Algorithm (GA) engineered for optimal scheduling within the solid wood panel processing line. AIOGA incorporates advanced features such as encoding strategy, population initialization, objective function setting, selection strategy, crossover operation, and mutation operation, demonstrating the methodological depth of the study. We applied AIOGA in a designed FJSP, and AIOGA substantially reduced the maximum completion time to 90 min. It evidenced an improvement of 39.60% over the conventional GA, enhancing the equilibrium of the equipment workload across the system. This research presents a multifaceted strategy to address the scheduling complications inherent in solid wood panel production and highlights the extensive applicability of adaptive intelligent optimization in diverse industrial settings. This study establishes a new paradigm in manufacturing optimization, underlining the valuable integration of sustainability and efficiency in production methodologies.

Development of bentonite-based organo-geopolymer hybrid wood binder

The study addresses concerns associated with formaldehyde-based adhesives in wood panel board production by proposing geopolymer-based wood binders as promising, formaldehyde-free alternatives. Using bentonite, the research delves into the development and performance properties of this geopolymer wood binder. The BET method was employed for the surface characterization of precursor raw materials for binder preparation. Si and Al elements identified through XRF analysis were correlated with characteristic bands in the FTIR spectrum. Alkaline activation solutions, employing sodium silicate and sodium hydroxide with a molar ratio range of 0.5 to 2.5 (SiO2:Na2O), revealed that binders with a molar ratio of 2.5 exhibited lower pH and higher adhesion strength. Different geopolymer formulations at solution to powder ratios (s/p) of 1.33, 3, and 3.5 determined s/p 3.5 as optimal for bentonite-based organo-geopolymer binders. Viscosity, gel time, pH, and solids content were examined, showing the effectiveness of substituting 10% silica fume to enhance the geopolymerization process and improve adhesion. Modifications using citric acid, sucrose, paraffin, pMDI, triacetin, and resorcinol demonstrated wet bonding strength comparable to urea formaldehyde adhesive. Analytical techniques, including FTIR spectroscopy, XRD analysis, and SEM EDX analysis, provided insights into functional groups, crystallographic properties, and microstructural characteristics. The concentration of Si and Al compounds on the bonding line, coupled with Na element diffusion, was observed through these analyses. Light microscopy of lap shear samples revealed a thinner bonding line, affirming effective binder penetration into wood cell lumens in bentonite-based organo-geopolymer binder formulations.

Handling-friendly, waterproof, and mildew-resistant all-bio-based soybean protein adhesives with high-bonding performance via bio-inspired hydrophobic-enhanced crosslinking network

Eco-friendly and formaldehyde-free soybean protein adhesives are highly attractive to the wood-based panel industry but typically suffer from low water-resistant bonding strength, high viscosity, and susceptibility to mildew. Inspired by adaptive hydrophobic and hydrophilic interactions of mussel foot proteins, herein, a high-performance and versatile all-bio-based adhesive (STF) was synthesized through employing bio-derived furfural and natural tannic acid to assist soybean protein in developing a biomimetic physical/chemical cross-linking network. The collaboration of the hydrophobic furan ring and the hydrophilic catecholic moiety endowed the as-prepared STF adhesives with exceptional water-resistant bonding strength, easy-coating performance, and mildew resistance. Compared to the original soybean protein, the optimal STF demonstrated dry and wet shear strengths of up to 2.52 MPa and 1.71 MPa, respectively, representing an increase of 65.8 % and 263.8 %. Notably, the aged bonding strength of STF surpassed that of previously reported soybean protein-based adhesives with a value as high as 1.19 MPa. The viscosity of the STF decreased by ≈ 98.1 % compared to the unmodified adhesive. Additionally, the STF exhibited excellent mildew resistance (no mildew for 7 days) and storage stability (> 72 h). Combined with life cycle assessment, the biomimetic STF adhesive holds great potential for large-scale production of environment-friendly wood panels.

Enhance the performance of steel-wood composite screw connections with fast-curing adhesive

In composite floors composed of the H-steel and the wood panel, screw connection is one of the design keys. In this paper, the method of using fast-curing epoxy resin to anchor the screw tip was proposed, and six sets of pull-out tests and five sets of push-out tests of epoxy-wood-combined anchored screws were conducted to analyze the influence of the effective meshing length and the epoxy meshing ratio on the connection performance, respectively. Firstly, compared with ordinary screws, the pull-out stiffness and strength of epoxy-anchored screws were increased by 79.8 % and 153.9 %, respectively. Secondly, compared with the ordinary screw connection, the initial shear stiffness and capacity of the steel-wood composite connection were increased by 60.0 % and 22.8 % when the epoxy meshing ratio was 0.25, respectively. Thirdly, the modified effective meshing length of epoxy-anchored screws was proposed. Finally, based on the calculation formula for screws with two plastic hinges in Eurocode 5, the two parameters of pull-out resistance and yield moment for the screw were modified, thus improving the calculation accuracy of shear capacity for combine-anchored screw connections by about 21.0 %.

Anthony Vidler's IAS Mystery

Abstract The honking of the geese going south was beginning to get on his nerves. How to work with that going on. And the library was getting colder. The day had been grey, the soil damp, the air raw and feeling like snow. It might snow tonight. Not a long walk home though—and the apartment was at least warm. If it wasn't for the people upstairs, creaking, stamping (or that's what it sounded like), and shouting—but maybe just talking given the thin walls. Maybe they were using Skype—his own had long since ceased to connect. Needs a new password, or better, someone to call. He had felt the walls this morning—damp and a little soft— old plasterboard, wooden panels slightly buckled from heat and damp in that order. How could they let the housing get so run-down? But that was how monasteries worked, and this, all said and done, was a sort of monastery. Without the religion of course. But religion was there all right—under the radar, couched in academic formulae, a kind of ersatz nonbelief in belief. He had heard it at lunch—the endless parroting of rehashed research, of half-baked theories, of platitudes about how good the food was, or how much better the food was yesterday, or how interesting the mixed cold vegetarian salad was, or that you couldn't count on anything these days, or you are new here aren't you? Kindly inquiries, sensitive overtures, only half-listening to the replies.

Review on line detection of wood panel images

In industrial, the modern intelligent degree of board counting is relatively low. Some small manufacturers still count by hand, but for large factories, manual counting needs a lot of human resources, and the accuracy of counting is low. With the rapid development of modern intelligence, image recognition is becoming more mature, some traditional algorithms keep emerging, such as Hough Transform, Fast Line Detector (FLD), Line Segment Detector (LSD) and other line detection algorithms, they have their own advantages and disadvantages, and are summarized and tested, compare which algorithm has higher accuracy and better effect in the field of board linear detection and counting. Finally, the operation mechanism, advantages and disadvantages are summarized, and the process and trend of the further optimization and development of the traditional algorithm line detection technology in the future are prospected, which provides some reference for the research in related fields.

Development of craquelure patterns in paintings on panels

Panel paintings are multi-layer structures composed of humidity-sensitive materials. Preventing or limiting stresses in these structures, generated by the loss or gain of moisture, requires an understanding of the relevant processes and risks. A three-dimensional elastic model of a panel painting was used to analyse surface stresses and understand how crack patterns are developed in the two-layer structure of the pictorial layer—the gesso and the paints. Two historically important paint types were considered—egg tempera and oil paints, laid on a gesso produced following historical procedures. Two scenarios of stress development were analysed: permanent cumulative drying shrinkage of paints or gesso, owing to gradual loss of water or evolution of the molecular composition of the binders, and moisture-induced cyclic swelling of the wood substrate. Ratios of distances between cracks in the tangential and longitudinal directions of a wood panel to the layer thickness were estimated for increasing magnitudes of materials’ dimensional change in the two scenarios. The critical values of the ratios for which stress in the midpoint between the cracks dropped below the value inducing strain at break in the materials and saturation of the crack patterns occurred, was approximately 3–4 or 5–6 for the paints and the gesso, respectively. The critical distance normalized to the gesso thickness between cracks parallel to the wood grain induced by cyclic swelling of the wood substrate due to relative humidity variation in the range of 50–70% was 6. The study demonstrated that crack spacings in the fully developed crack systems remain sensitive only to the thicknesses of paint or gesso layers which, therefore, can be derived from the crack pattern geometry. Existing flaws in gesso were found not to increase the risk of new crack development.

Aerodynamic investigation of the turbulent flow past a louvered-fin-and-tube automotive heat exchanger

Turbulent flow past a radiator contributes to noise emission when interacting with a downstream cooling fan. This study examines turbulent flow characteristics downstream of a radiator, focusing on turbulence production, dissipation, non-homogeneity, and anisotropy. We assess turbulence models based on isotropy and homogeneity for noise prediction in real applications. Results show significant non-homogeneity due to the radiator grid’s wakes, extending downstream to a region where the fan would be located. Flow in this region trends toward isotropy, especially when considering a downstream circularly-holed wood panel mimicking the flow contraction caused by a fan casing. The radiator core’s fins and louvers break down vortical structures more than generating large eddies, as reported in studies involving heat exchangers with larger gaps between cooling pipes. The von Kármán turbulence model approximates the experimental spectrum, but caution is needed with rapid flow acceleration. This investigation enhances our understanding of turbulence characteristics in the vicinity of radiators with implications for noise spectrum prediction and modeling in such systems.

Research on color matching model for wood panel furniture based on a back propagation neural network

The wood furniture manufacturing industry continues in the direction of customized furniture. The analysis of color collocation is important for developing customized furniture. This study summarizes the common color collocation application area for porch cabinets. After selecting the appropriate color model, C # language was used to simulate a real scene setting experimental system in the Unity graphics engine. Colors were generated randomly in the corresponding area, and subjects evaluated the harmony. Then, the Python language was used to build the BP neural network model. The BP neural network models were trained using the Hue, Saturation, value (HSV) of the depicted colors and their corresponding scores. Finally, the evaluation model of color collocation and harmony was obtained. The model can be used to improve the prediction of color matching in customized furniture, which will promote enterprise productivity and industry development.

World’s concentration of forest products exports

The world’s economy has undergone several changes and crises that may have altered the dynamics and structure of the forestry market after 2008. Thus, the objective of this study was to measure the concentration of the international market of the main forest products between 2008 and 2018. We used the Concentration Ratio [CR(k)], Hirschman-Herfindahl Index (HHI), Theil Entropy Index (E) and Gini Coefficient (G) to evaluate the forest products concentration. Our results showed that American and Asian countries have risen and taken positions of major forest products exporters to European markets over the years. The main exported product was “Paper and cardboard”, followed by “Lumber”, “Pulp”, “Wooden panels”, “Wood for industrial purposes” and “Energy”. Brazil's global share stood out in the pulp and paper segments. The forest products market concentration was classified as low for CR4, moderately low for CR8, unconcentrated and highly competitive for HHI and Entropy indices. Furthermore, the market was classified with inequality from very strong to absolute using the Gini index indicating that exports come from a small number of nations.

Attractiveness of municipalities in Minas Gerais for the installation of forest-based companies

This paper measured the attractiveness of municipalities in the state of Minas Gerais (MG) for projects in the steel, cellulose and paper, furniture, energy and wood panel industry segments. A questionnaire was used to construct an index of attractiveness of the forestry sector for each municipality. As a result, it was found that 40% of the municipalities presented “average” or higher attractiveness. The mesoregions with the greatest potential for forestry development were the Metropolitan region of Belo Horizonte, Southwest of Minas and Zona da Mata. The steel and cellulose and paper segments found attractive factors in 74.08% and 72.79% of the municipalities, respectively. It was concluded that the methodology applied showed how close a location was to meeting the characteristics of forest-based industries. It is expected to encourage future research and influence strategic planning for the expansion of the forestry sector across the country.

An efficient and accurate surface defect detection method for quality supervision of wood panels

The wood panel processing sector is integral to the landscape of industrial manufacturing, and automated detection of wood panel surface defects has become an important guarantee for improving the efficiency and quality of processing production. However, due to the diverse scales and shapes of wood panel surface defects, as well as their complex and varied colors and texture characteristics, the efforts to efficiently and accurately detect surface defects in wood panels through existing methods have fallen short. Therefore, the paper proposes an enhanced YOLOx-tiny deep learning network for wood panel surface defect detection. We introduce new modules multi-pooling feature fusion module and comprehensive feature extraction module, instead of the original SPP and Bottleneck modules to enhance key feature extraction and reduce the number of computational parameters. The experimental results conducted on the self-constructed wood panel surface defects dataset show that the mAP of our proposed method is 95.01%, which is 9.58% higher than the original YOLOx-tiny network model, and the defects recall is 91.46%, which is 13.21% higher compared to the original network. Meanwhile, the method is able to reduce 12.22% of computational parameters, which effectively improves the efficiency of the detection of surface defects on wood panels. In summary, the proposed intelligent surface defect detection approach for wood panels, which utilizes an enhanced YOLOx-tiny deep learning network, has yielded notable outcomes in enhancing both accuracy and efficiency. This method holds significant practical relevance for the wood panel manufacturing sector, offering the potential to enhance both production efficiency and quality. It also explores the automation and intelligent technology in the process of man-made board processing, which provides a valuable reference for the research in related fields.

Wooden Rehearsal Rooms from the Construction Process to the Musical Performance

Rehearsal rooms play an important role in musicians’ activities to obtain the best results during a performance in front of an audience. Numerous rehearsal rooms are located in complex buildings, such as opera houses and cultural centers, where new research outcomes have led to increasingly complex projects and construction phases. Furthermore, technical complexity has also increased due to the large quantity of used materials and the innovation level of the process. In this context, a new methodology becomes mandatory to control the indoor air quality and the acoustic quality in rehearsal rooms. This paper aims to offer a procedure for rehearsal rooms for large ensembles during the construction and life cycle phases to optimize the indoor environmental quality according to different types of ensembles and repertoires. In particular, rehearsal rooms with wood panel cladding are considered. The proposed methodology is controlled by a digital twin (DT) based on building information modeling (BIM), integrated with acoustic measurements, sensors and actuators aimed at implementing the database in real time. A case study is presented, in which the cladding system is described, the new methodology is applied, and the results are compared with the criteria suggested in the standard ISO 23591.

Exploring the inner hygro-mechanical behaviour of historical panel paintings: a novel approach using digital twins

Wooden Panel Paintings (WPPs) stand as invaluable cultural artefacts from the past. These works present an intriguing challenge in understanding their complex mechanical behaviour and ensuring their long-term preservation. The present study assumes as founding paradigm the unicity of each WPP, in terms of its material composition, historical background, physical dimensions, and the specific environmental conditions it has been subjected to over time, and their complex behaviour, which requires the knowledge of both mechanical and materials specificity. These characteristics need to be considered, and studied in-depth for each individual WPP, particularly if the aim is to develop a comprehensive understanding of its individual mechanical behaviour. The study provides new computational models calibrated to reproduce the physical and mechanical behaviour of artworks and acting as their 'digital twins'. The models developed contribute significantly to the understanding of the mechanics of these artworks, including the impact of environmental thermo-hygrometric fluctuations and the role of structural elements such as crossbeams. The results, corroborated by experimental analyses, indicate that environmental variations, both short and long term, exert specific and quantifiable effects on the WPPs, and that the presence of crossbeams significantly influences the distribution of stresses within the panel, particularly affecting the pictorial layers that are often the most susceptible to damage. In this context the generated digital twins serve as an invaluable tool, offering the potential to simulate various risk scenarios or to evaluate the effectiveness of engineered conservation interventions on the WPPs.

Improving feedstock quality control in formaldehyde-based resin and wood-based panel production through near infrared spectroscopy

To assure the quality control of industrial processes, it is important to adopt reproducible and efficient methodologies. Spectroscopic methods, such as near infrared (NIR), are a good option as they are fast and may be used to indirectly estimate multiple physicochemical properties. In this study, NIR spectra of key feedstock samples used in the production of formaldehyde-based resin and wood-based panels, namely urea, ammonium sulfate, ammonium nitrate, sodium hydroxide, and acetic acid, were acquired. Multivariate data analysis was applied to establish the correlation between the spectra and the properties being measured. Quantitative models were then created using partial least squares regression to predict the concentrations of feedstock samples. This study presents quantitative models that were created by combining spectra measured on two probes, which achieved similar prediction results as single-probe based models. The performances of the best models were compared with the reference methods for each of the evaluated samples. For the samples under study, the proposed approach is suitable for routine analysis across multiple equipment configurations using the same quantitative model. NIR spectroscopy combined with chemometric models could be a valuable complement to support in-line raw material monitoring and plant digitalization in the wood panels industry.

Hydrochar-based facile and greenwood bio-adhesives production from distilled spent grain

The use of urea-, melamine-, and phenol–formaldehyde resin adhesives is endangering human health and damaging the environment. Developing formaldehyde-free plywood bio-adhesive is becoming a hot spot, and this study, for the first time, reports the preparation of facile and green wood bio-adhesives using hydrochar derived from distilled spent grain (DSG) by hydrothermal carbonization (HTC), which is promising for treating and valorizing high-moisture bio-waste such as DSG. HTC contributed to the dewatering, screening, and activation of active components in DSG, benefiting their interactions with cross-linkers and wood panels. The results show that the HTC temperature can significantly affect the reaction activity of hydrochar, thus influencing bonding strength. BD-180 bio-adhesive (mixture of cross-linkers glycerol triglycidyl ether/polyvinyl alcohol and hydrochar from HTC of DSG at 180 °C) had an excellent wet shear strength (1.24 MP), meeting the Chinese national standard GB/T 9846–2015 (≥0.7 MPa). Maillard reaction was a key reaction during HTC to destroy the secondary structure of proteins, resulting in the release of abundant –OH and –NH2. These functional groups in hydrochar were the major active sites available for the formation of covalent bonds (e.g., C–N and C–O–C) between bio-adhesive and wood panels, promoting the improvement in wet shear strength of bio-adhesives. This work provides a new method for the valorization of DSG and contributes to the development of green wood bio-adhesives without formaldehyde problems.

Assumption of the Virgin by P.P. Rubens: On a Modello from 1611

An Assumption of the Virgin (c. 1611˗13) was painted by Rubens for the High Altar of Antwerp Cathedral and is now part of the collections of the Kunsthistorisches Museum in Vienna. On 22 April 1611, Rubens (successfully) submitted two modelli. One modello in the Hermitage Museum in St Petersburg is widely accepted as one of the two. The second has not been convincingly identified yet. Rubens’ Assumption of the Virgin in the Royal Collection in London (c. 1613 or later) has been the subject of much discussion. The (previously unpublished) panel that emerged in Antwerp a few years ago is therefore most interesting. Dendrochronological research (KIK-IRPA) has shown that its wooden panel (consisting of three oak planks) came from a tree cut down in about 1590. Our modello differs from the London version, for instance, in the Virgin’s right palm (turned upwards) and in two angels holding each other’s arm who appear to the right in a cloud. The question of Rubens’ Assumption of the Virgin of 1611 drew the attention of several art historians, many of them rejecting the London panel as clearly being of a later date. The comparison of the Hermitage modello with our picture supplies interesting analogies, like the representation of the young women on the left. Similarities in the faces of the angels carrying the Virgin and especially the angel with blonde hair are striking.