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The surface characteristics of thermally and chemically modified wood, such as surface roughness, surface free energy (SFE) and wettability, are important properties that influence further manufacturing processes such as gluing and coating. The aim of this paper was to determine the influence of the surface roughness of thermally and chemically modified teak wood on their SFE, wettability and bonding quality for water-based acrylic and solvent-based alkyd varnishes. In addition, durability against subterranean termites in the field of these modified teak woods was also investigated to give a valuable information for their further application.

The woods tested in this study were fast-growing teak woods that were prepared in untreated and treated with furfuryl alcohol (FA), glycerol maleic anhydride (GMA) and thermal. SFE values were calculated using the Rabel method. The wettability values were measured based on the contact angle between varnish liquids and wood surfaces using the sessile drop method, and the Shi and Gardner model model was used to evaluate the wettability of the varnishes on the wood surface. The bonding quality of the varnishes was measured using a cross-cut test based on ASTM 3359-17 standard. In addition, durability against subterranean termites in the field of these modified teak woods was also investigated according to ASTM D 1758-06.

The results showed that furfurylated and GMA-thermal 220°C improved the durability of teak wood against termites. The furfurylated teak wood had the roughest surface with an arithmetic average roughness (Ra) value of 15.65 µm before aging and 27.11 µm after aging. The GMA-thermal 220°C treated teak wood was the smoothest surface with Ra value of 6.44 µm before aging and 13.75 µm after aging. Untreated teak wood had the highest SFE value of 46.90 and 57.37 mJ/m² before and after aging, respectively. The K values of untreated and treated teak wood increased owing to the aging treatment. The K values for the water-based acrylic varnish were lower than that of the solvent-based alkyd varnish. The untreated teak wood with the highest SFE produced the highest bonding quality (grades 4–5) for both acrylic and alkyd varnishes. The solvent-based alkyd varnish was more wettable and generated better bonding quality than the water-based acrylic varnish.

The originality of this research work is that it provides evaluation values of the durability and SFE. The SFE value can be used to quantitatively determine the wettability of paint liquids on the surface of wood and its varnish bonding quality.

Using a soft-hard continuum of drivers and barriers, this research seeks to explain wood companies' adoption of circular economy (CE) practices.

Multiple interviews, complemented by secondary documents and site observations were used to investigate three wood-based companies that have adopted CE practices. The 10R framework and soft-hard continuum are used to guide data analysis.

The adoption of 10R practices were explained by soft-factor incentives of leaders' values and vision and openness for innovation, all within a regulatory void, and eventually overcome hard-factor barriers of process development, supply chain capability and customer behaviours at product end-of-life.

Crucial for CE model adoption are leaders' positive attitudes, subsequently grown across the companies. The 10Rs are a prompt for CE practice adoption to capture and retain value and generate revenue. Collaboration across the supply chain, including customers and other value capture companies (e.g. repurposing companies), is essential to maximise value retention. Government should play an increased soft-factor incentive regulatory role and support CE practices to overcome hard-factor barriers.

This study contributes an explanation of CE adoption within a relatively unsupported context. Despite the regulatory void, CE practice adoption was driven by leader values. To achieve their vision and overcome the numerous barriers, suppliers and customers required a large investment in education. Indeed, customer behaviour, previously thought to be an incentive for CE adoption, is also identified as a barrier.

The transparency of wood to microwave radiation is subject to changes in the wood's properties caused by softening of the wood material during fungal attack or the addition of moisture. A prototype microwave system that measures microwave attenuation and phase delay between two antennae was developed to detect fungal decay in wood at equilibrium moisture content. A total of twelve wooden stakes of 200 x 65 x 65 mm Pinus radiata (softwood) and twelve stakes of Eucalyptus regnans (hardwood) of the same dimensions were exposed to soil containing decay fungi for 12, 16, 20 and 24 weeks in an Accelerated Field Simulator (AFS), which is a climate conditioned room that simulates humid tropical conditions. A control set of three stakes of each wood type was also included in the experiment. Samples were washed and dried in an oven before testing with the prototype system. Orienting the antennae such that the microwave field was perpendicular to the wood grain could not distinguish between sound and decayed wood; however orienting the antennae so that the microwave fields were parallel to the wood grain and having the antennae pressed against the wood sample easily distinguished between sound wood and decayed wood. The phase delay data could not distinguish between sound or decayed wood.

The fire resistance of timber structures is heavily dependent on the fire behaviour of the connections between its structural elements. The experimental study presented in this paper aimed to investigate the fire performance of glued-laminated timber beam connections reinforced perpendicular-to-wood grain with self-tapping screws (STS).

Two full-size fire experiments were conducted on glulam beam-end connections loaded in flexure bending. Two connection configurations, each utilizing four steel bolts arranged in two different patterns, were reinforced perpendicular to wood grain using STS. The bolt heads and nuts and the steel plate top and bottom edges were fire protected using wood plugs and strips, respectively. Each connection configuration was loaded to 100% of the ultimate design load of the weakest unreinforced configuration. The test assemblies were exposed to elevated temperatures that followed the CAN/ULC-S101 standard fire time–temperature curve.

The experimental results show that the influence of the STS was significant as it prevented the occurrence of wood splitting and row shear-out and as a result, increased the fire resistance time of the connections. The time to failure of both connection configurations exceeded the minimum fire resistance rating specified as 45 min for combustible construction in applicable building codes.

The experimental data show the effectiveness of a simple fire protection system (i.e. wood plugs and strips) along with the utilization of STS on the rotational behaviour, charring rate, fire resistance time and failure mode of the proposed hybrid mass timber beam-end connection configurations.

In fire condition, the time to failure of a timber connection is mainly reliant on the wood charring rate, the strength of the residual wood section, and the limiting temperature of the steel connectors involved in the connection. The purpose of this study is to experimentally investigate the effects of loaded bolt end distance, number of bolt rows, and the existence of perpendicular-to-wood grain reinforcement on the structural fire behavior of semi-rigid glued-laminated timber (glulam) beam-to-column connections that used steel bolts and concealed steel plate connectors.

In total, 16 beam-to-column connections, which were fabricated in wood-steel-wood bolted connection configurations, in eight large-scale sub-frame test assemblies were exposed to elevated temperatures that followed CAN/ULC-S101 standard time-temperature curve, while being subjected to monotonic loading. The beam-to-column connections of four of the eight test assemblies were reinforced perpendicular to the wood grain using self-tapping screws (STS). Fire tests were terminated upon achieving the failure criterion, which predominantly was dependent on the connection’s maximum allowed rotation.

Experimental results revealed that increasing the number of bolt rows from two to three, each of two bolts, increased the connection’s time to failure by a greater time increment than that achieved by increasing the bolt end distance from four- to five-times the bolt diameter. Also, the use of STS reinforcement increased the connection’s time to failure by greater time increments than those achieved by increasing the number of bolt rows or the bolt end distance.

The invaluable experimental data obtained from this study can be effectively used to provide insight and better understanding on how mass-timber glulam bolted connections can behave in fire condition. This can also help in further improving the existing design guidelines for mass-timber structures. Currently, beam-to-column wood connections are designed mainly as axially loaded connections with no guidelines available for determining the fire resistance of timber connections exerting any degree of moment-resisting capability.

CELLULOSE is Nature's strong material. It is the chief constituent of cotton flax and wood. Wood can be turned into sugars by treatment with hydrochloric acid Bergius process) and by certain termites; horses and cows break down the cellulose in grass into sugar before digesting it. So it is not surprising that the cellulose polymer is built up of what are practically molecules of a glucose (“Barley Sugar”). Each β glucose unit is twisted about its axis through 180 deg.; the combination of two such units makes up that is called a cellulose unit which has the structure shown in Fig. 2. The cellulose polymer is a long, straight chain made up from these cellobiose units, and each chain probably contains about 70 such units.

Conventional motion mechanisms in adaptive skins require rigid kinematic mechanical systems that require sensors and actuation devices, hence impeding the adoption of zero-energy buildings. This paper aims to exploit wooden responsive actuators as a passive approach for adaptive facades with dynamic shading configurations. Wooden passive actuators are introduced as a passive responsive mechanism with zero-energy consumption.

The study encodes the embedded hygroscopic parameters of wood through 4D printing of wooden composites as a responsive wooden actuator. Several physical experiments focus on controlling the printed hygroscopic parameters based on the effect of 3D printing grain patterns and infill height on the wooden angle of curvature when exposed to variation in humidity. The printed hygroscopic parameters are applied on two types of wooden actuators with difference in the saturation percentage of wood in the wooden filaments specifically 20% and 40% for more control on the angle of curvature and response behavior.

The study presents the ability to print wooden grain patterns that result in single and double curved surfaces. Also, printing actuators with variation in infill height control each part of wooden actuator to response separately in a controlled passive behavior. The results show a passive programmed self-actuated mechanism that can enhance responsive façade design with zero-energy consumption through utilizing both material science and additive manufacturing mechanisms.

The study presents a set of controlled printed hygroscopic parameters that stretch the limits in controlling the response of printed wood to humidity instead of the typical natural properties of wood.

Various modifications of polyvinyl acetate emulsion wood adhesive were made and their performance evaluated in standard tests. The results are interpreted in the context of adhesion theories and the chemical structures of the polymers and wood. The adhesion of the polymers to wood and the cohesive strength of the polymers are the two predominant factors determining the performance of the adhesives. Adhesive strength in thermosetting resins is enhanced by irreversible chemical reactions that create extensive networks within the adhesive layer and strong bonds to the wood substrate, leading to strong and durable joints that passed all of the performance evaluation tests. Most of the PVAc emulsions exhibited good adhesive performance in the dry state, but failed in water soak and boiling water immersion tests since their adhesion and cohesion are mainly based on weaker physical interactions. Emulsions with (hard) core‐(soft) shell morphology and correspondingly high glass transition temperatures gave poor performance under all conditions.

Taking the perspective of a start-up company, the purpose of this paper is to analyse resource renewal in heavy business networks.

The theoretical framework is based on the Industrial Network Approach and, especially, the resource interaction framework, business network settings and studies of starting up in business networks. The basis for the paper is a case study of a start-up in the Swedish wind energy context.

Resource renewal in this case means replacing one resource, having implications for the resource interfaces in the three business network settings.

The paper contributes to the area of studies of starting up in business networks by identifying a distinct form of resource renewal in heavy business networks enabled by development of resource interfaces in three business network settings.

Managers in start-ups as well as established firms need to interact to create and develop the resource interfaces that are needed to achieve resource renewal. Resource renewal not only is in the hands of start-ups but also requires interactive resource development with various collaboration partners.

This study takes a start-up’s perspective to resource renewal of heavy business networks and analyses heaviness based on resource interfaces in three business network settings.

Wood is one of the materials that is used for building construction either as structural member or as finishes from ages past to contemporary generation. It is composed of elongated, hollow spindle shaped cells that are arranged parallel to each other along the trunk of a tree. The resistance to water, chemicals, strength properties, appearance and decay rate is dictated by the fibrous cells. The purpose of this paper was to examine the application and use of wooden floor finish (an extract from wood) in residential buildings in Lagos, Nigeria, with a view to determine its effectiveness.

The study adopted a dual stage survey approach before the administration of questionnaire on 100 respondents that were selected through purposive sampling after the initial inquiry on the use of the material from 384 randomly selected samples from the entire population.

The study shows that the material is applied in all interior spaces except bathrooms and toilets. Minimal adoption is also seen in the kitchen area. Users indicate that wooden floor finish requires little maintenance, has low impact on users' health, considered safe-minimal occurrence of home accidents is recorded, has moderate thermal insulation and affordable.

The usage has impact on the environment due to continuous lumbering activities and lack of adequate plan for reforestation. This suggests that its sustainability depends on afforestation programmes. Its poor performance in sound insulation, water and fire resistance requires further attention. The maintenance is relatively easy and affordable.

The author made a new foray into investigating the performance of wooden floor finish due to its resurgence in the area bearing in mind the unseasoned condition of wood in circulation in the area. Previous adoptions were done by a less aggressive generation of well-trained artisans. Best places for its usage within the interior spaces are identified.