Search Results (42)

Traditional villages contain rich natural and humanistic information, and exploring the spatial distribution characteristics and cultural landscape zoning of traditional villages can provide scientific support for their centralized and continuous protection and renewal and sustainable development. In this study, 326 traditional villages in the northern Henan region were taken as the research object, followed by analyzing their spatial distribution characteristics by using geostatistical methods, such as nearest-neighbor index, imbalance index, geographic concentration index, etc., combining the theory of cultural landscape to construct the traditional villages’ cultural factor index system, extracting the cultural factors of the traditional villages to form a database, and adopting the K-means clustering method to divide the region. The results show that the spatial distribution of traditional villages in northern Henan tends to be concentrated overall, with an uneven distribution throughout the region. The density is highest in the northwestern part of Hebi City and lower in the central and southern parts of Xinxiang City, Neihuang County, and Puyang City. Based on the cultural factor index system, the K-means algorithm divides the traditional villages in northern Henan into six clusters. Among them, the five cultural factors of topography and geomorphology, building materials, courtyard form, structural system, and altitude and elevation are the most significant, and they are the cultural factors that dominate the landscape of the villages. There is a significant correlation between topography, altitude, and other cultural factors, while the correlation between the street layout and other factors is the lowest. Based on the similarity between the clustering results and the landscape characteristics, the traditional villages in northern Henan can be divided into the stone masonry building culture area along the Taihang Mountains, the brick and stone mixed building culture area in the low hills of the Taihang Mountains, the brick and wood building culture area in the North China Plain, and the raw soil building culture area in the transition zone of the Loess Plateau. Full article

This work studies the presence and evolution of wood construction in urban environments, using Santiago province in Chile as a relevant comparative case. The first part of the study analyzes the spatial and temporal distribution of wood-based structures in Santiago, showing that although wood has historically been used in low-rise housing, its presence has declined significantly due to increasing urban densification and the widespread adoption of materials like concrete for taller buildings. Currently, only 5.4% of Santiago’s buildings use wood structures, with their presence notably decreasing in the high-density municipalities of the city. Recent construction trends in Santiago show that the average building height is 12 stories, with timber buildings not exceeding 6 stories, despite the absence of specific restrictions in the building code for tall timber structures. The second part of this study contrasts these trends with the global development of tall timber buildings (six stories or more), which total approximately 300 worldwide as of 2024. The leading cities include Paris (with over 35 buildings) and London (over 17), followed by Zürich, Vancouver, and Portland. This study highlights the pivotal role of wood promotion policies in enabling this global expansion. Finally, a five-phase classification is proposed to evaluate the evolution of tall timber construction in a given city, emphasizing the role of public policy in enabling large-scale adoption, especially for cities such as Santiago. Full article

In the industry sector, it is very common to have different types of dissimilar materials on the same construction rather than products made from a single type of material. Traditional methods (welding, mechanical fastening, and adhesive bonding) and hybrid techniques (friction stir welding, weld bonding, and laser welding) are used in the assembly or joining of these materials. However, while joining similar types of materials is relatively easy, the process becomes more challenging when joining dissimilar materials due to the structure and properties of the materials involved. In recent years, additive manufacturing and 3D printing have revolutionized the manufacturing landscape and have provided great opportunities for the production of polymer-based multi-materials. However, developments in the joining of multi-material parts are limited, and their limits are not yet clear. This study focuses on the joining of 3D-printed products made from PLA-based multiple materials (PLA and PLA Wood) using friction stir welding. Single-material and multi-material parts (with 100% infill ratio and three different combinations of 50% PLA/50% PLA Wood) were welded at a feed rate of 20 mm/min and three different tool rotational speeds (1750, 2000, and 2250 rpm). Tensile and bending tests were conducted on the welded samples, and temperature measurements were taken. The fractured surfaces of the samples were examined to perform a damage analysis. It is determined that the weld strength of multi-materials changes depending on the combination of the material (material design). For multi-materials, a welding efficiency of 74.3% was achieved for tensile strength and 142.68% for bending load. Full article

The straight mortise and tenon joints (SMTJs) of Tusi Manor, situated in the Yunnan–Tibet region of China, tend to undergo decay. This study aims to investigate the mechanism performance degradation of SMTJs due to decay. Five full-scale SMTJs were constructed and incubated with wood-rot fungi for 0, 6, 12, 18, and 24 weeks. Cyclic loading tests were conducted to assess the damage mechanisms and extent of mechanical property degradation at these different stages of decay, supported by ABAQUS finite element simulation software. The results revealed a progressive increase in damage with prolonged decay time. Comparison between decayed and undecayed specimens showed a maximum load-bearing performance degradation rate of 5.17%, 11.83%, 17.34%, and 23.54% after 6, 12, 18, and 24 weeks of fungal incubation, respectively. The cumulative energy efficiency degradation rates were 8.38%, 9.51%, 23.13%, and 33.31%, respectively. SMTJs mechanical performance degradation is correlated with wood mechanical property degradation as a function of the S-family. Finite element simulations further indicated a reduction in tenon strength from the outer parts towards the inner parts of the structure. Full article

Historical buildings are constructed using a variety of materials, including stone, wood, and combinations thereof. These structures serve as tangible links to the past and are of great importance to cultural heritage, thus necessitating their protection. Throughout history, these buildings and materials have been exposed to various environmental conditions, including climate, wind, humidity, and seismic activity. This study focused on the Florya Atatürk Marine Mansion, Istanbul, a coastal structure situated at the shoreline and subject to the effects of wind, moisture, and sea salt. The mansion is primarily constructed from pinewood, and due to the complexity of the material salt can cause deterioration that poses a threat to the building’s cultural and historical value. With a focus on seasonal variations, this study explored the relationship between the mechanical properties and monetary values of the pinewood materials used in the waterfront mansion. To achieve this, samples were naturally aged in a saline environment by the sea and subjected to tensile and bending tests at the end of each season. The resulting mechanical properties were compared to computer simulations using finite element methods. By subtracting the specific depreciation rate of the material at the end of each season, a relationship between mechanical properties and monetary value was calculated and presented in graphical form. It was found that the material’s mechanical properties varied throughout the year, affecting its monetary value in different ways. Therefore, optimal maintenance should be provided before January to preserve the economic value of the material, considering temperature change, exposure to direct sunlight, and humidity, which have direct effects on the front and back parts of the building. Full article

The Cathedral of Florence is one of the largest churches in the world and is known for one of the most famous domes ever, which characterizes the skyline of the city. The dimensions of the building mean that the dimensions of the roof are equally large and so are the wooden structures that support it. The roof of the cathedral is organized on two levels: the roof of the large central nave and, at a lower level, those of the two lateral naves. The purpose of this paper is the identification of the wood species of which the structures are made. The sampling method of the 408 samples that have been identified is then described, the methods followed to reach a reliable identification and finally the results. The timbers most represented among the structural elements are those of silver fir, chestnut and elm. Other timbers are then found in the other components less directly linked to the main structural parts that make up the trusses. The paper then discusses the technological implications on the use of those woods within the wooden covering structures of the cathedral and the main sources of timber that the builders had available, in particular the Casentino forests that the Municipality of Florence had donated to the structure that managed the construction of the cathedral (Opera di Santa Maria del Fiore—OPA). OPA still exists today and is responsible for the maintenance of the cathedral and other annexed buildings. Full article

The mechanical strength of wood from Scots pine (Pinus sylvestris), European larch (Larix decidua), and Norway spruce (Picea abies) was studied using static compression tests. The material was exposed under constant soaking in water with salinity of 7‰. The liquid mix was prepared according to a value roughly equivalent to the average salinity along the entire length of the Baltic Sea. The mechanical strength and quality of the raw material were determined using a sea salt saturation test, which determined the adhesion of the raw material to the extrusion process (permissible stress). An investigation was conducted to determine the physicochemical parameters of the material that was tested. It was investigated how much mineral compounds were absorbed over four cycles lasting a total of six weeks during the test. According to the statistical analysis, the chemical composition of wood and the presence of salts and mineral compounds correlated with its mechanical strength. An important part of the study focused on examining the factors affecting the construction of coniferous wood structures. The preparation of the raw material correctly can provide information on how the material can be protected during exposure to specific environmental conditions for longer. Full article

Windmills constitute a valuable part of cultural heritage, especially in Greece, as unique structures of popular architecture and know-how of the pre-industrial era. Their wooden mechanisms were of exceptional constructional ingenuity, with the Mediterranean ones bearing a vertical wing and a rotating roof (“trula”), with a manual torsion mechanism that allowed for operation in all wind directions. Sikinos is a small Aegean island characterized by rich landscapes, which do not have wood-producing forests, but only sparse Juniperus phoenicea shrub land mixed with evergreen hardwood species and the presence of numerous sclerophyllus vegetation species (maquis). Three abandoned windmills are still preserved on the island today, but only two of them appear to have their wooden mechanisms left. In the one windmill mechanism examined, it was found that different wood species were used to manufacture its individual parts. Oak wood was used in most of the large elements, with the exception of the sprattle beam (“zigos”), which is made of fir wood. The local juniper was not used in any crucial part of the mechanism, though it was used only as a structural material on the first floor (“anogio”) flooring, along with large-diameter olive trunks. The findings of this study highlighted the thorough knowledge of the properties of various wood species and the effective use of simple tools toward the construction of functional and effective windmill mechanisms. Full article

Climate change and the subsequent increase in global mean air temperature already present a significant impact on forest vegetation. Especially in the near future, several forest species are expected to be in danger of extinction or compelled to migrate to colder regions. Some common species will be replaced by highly climate-tolerant species, primarily exotic plants, among others. The tree of Ailanthus, or “tree-of-heaven”, as it is widely known, constitutes a rapidly growing plant, considered to be native to parts of China, while since the middle of the 18th century, it gradually spread to Europe and North America. This species demonstrates a preference for warmer, drier environments, although it can also survive in a variety of habitats and endure pollution of urban areas. It is a species with several uses, such as for animal feed, fuel, timber, pharmaceutical applications, etc., while its suitability for specialized applications of high-added-value is constantly being investigated. Its wood has a desirable appearance and characteristics that are comparable to those of other hardwood species of similar densities/weight. This article discusses some of the most important characteristics of Ailanthus wood and presents a comprehensive and constructive review of the chemistry, pharmacology, traditional and innovative uses, quality control, biological resistance, potential utilization in bioenergy and biofuels and wood products (e.g., wood-based panels, other advanced structure materials, etc.), use challenges and limitations, in order to contribute to the utilization potential assessment of this species biomass. Full article

The intensive construction of all categories of roads and the very demanding maintenance of the pavement structures of existing roads due to ever-increasing traffic loads confronts us with a lack of resources and also an increase in cost for the constituent materials of asphalt mixtures. On the other hand, there is another problem: large amounts of waste material in the form of bio-ash, which is obtained by burning waste wood biomass in the production of thermal energy and/or electricity. In order to solve the environmental problem of bio-ash disposal, research was conducted on the use of waste bio-ash as a constituent material in asphalt pavements. As part of this study, the effect of asphalt concrete mix, with bio-ash as a filler, on the release of harmful substances into the environment was investigated. The possibility of using wood bio-ash (BA) as a filler in asphalt mixtures was then determined through physical and mechanical property tests. The properties of the asphalt sample’s sensitivity to the action of water (indirect tensile strength ratio—ITSR) and resistance to rutting were tested for asphalt concrete type AC 11 surf with 50% bio-ash in the filler. It was established that asphalt concrete does not release harmful substances into the environment and that the 50% share of bio-ash in the filler results in asphalt that has good resistance to water sensitivity and even greater resistance to rutting. Full article

The wood of Michelia macclurei Dandy (MD) is an excellent material that is widely used in the furniture, handicraft, and construction industries. However, less research has been conducted on the chemical composition and biological activity of heartwood, which is the main valuable part of the wood. This study aimed to investigate the chemical composition and biological activities of the heartwood of Michelia macclurei Dandy (MDHW) and to confirm the active ingredients. Triple quadrupole gas chromatography–mass spectrometry (GC-MS) was used to characterize the volatile components of MDHW, while ultra-performance liquid chromatography–mass spectrometry was used to analyze the non-volatile components (UPLC-MS). The total reducing power, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging assays, acetylcholinesterase and α-glucosidase inhibition assays, and an antimicrobial test of 4 gram bacteria were used to describe the in vitro bioactivities. The GC-MS analysis showed that the volatile components of MDHW were mainly fatty compounds and terpenoids, with sesquiterpenes and their derivatives dominating the terpene composition. β-elemene was the main terpene component in the steam distillation (11.88%) and ultrasonic extraction (8.2%) methods. A total of 67 compounds, comprising 45 alkaloids, 9 flavonoids, 6 lignans, and others, were found by UPLC-MS analysis. The primary structural kinds of the non-volatile components were 35 isoquinoline alkaloids. Alkaloids were the predominant active constituent in all MDHW extracts, including crude extracts, alkaloid fractions, and non-alkaloid fractions. These extracts all demonstrate some biological effects in terms of antioxidant, enzyme inhibition, and bacterial inhibition. The findings of this study show that MDHW is abundant in chemical structure types, has great bioactivity assessment, and has the potential to be used to create natural antioxidants, products that postpone Alzheimer’s disease and lower blood sugar levels and antibacterial agents. Full article

A series of composites based on epoxy resin filled with additives of natural origin were prepared to investigate the influence of such fillers on the properties of the epoxy compositions. For this purpose, the composites containing 5 and 10 wt.% of additive of natural origin were obtained using the dispersion of oak wood waste and peanut shells in bisphenol A epoxy resin cured with isophorone-diamine. The oak waste filler had been obtained during the assembly of the raw wooden floor. The performed studies include testing of samples prepared using unmodified and chemically modified additives. Chemical modification via mercerization and silanization was performed to increase the poor compatibility between the highly hydrophilic fillers of natural origin and the hydrophobic polymer matrix. Additionally, the introduction of NH₂ groups to the structure of modified filler via 3-aminopropyltriethoxysilane, potentially takes a part in co-crosslinking with the epoxy resin. Fourier Transformed Infrared Spectroscopy (FT–IR), as well as Scanning Electron Microscopy (SEM), were carried out, to study the influence of performed chemical modification on the chemical structure and morphology of wood and peanut shell flour. SEM analyses showed significant changes in the morphology of compositions with chemically modified fillers, indicating improved adhesion of the resin to lignocellulosic waste particles. Moreover, a series of mechanical (hardness, tensile strength, flexural strength, compressive strength, and impact strength) tests were carried out, to assess the influence of the application of fillers of natural origin on the properties of epoxy compositions. All composites with lignocellulosic filler were characterized by higher compressive strength (64.2 MPa—5%U-OF, 66.4%—SilOF, 63.2—5%U-PSF, and 63.8—5%SilPSF, respectively), compared to the values recorded for the reference epoxy composition without lignocellulosic filler (59.0 MPa—REF). The highest compressive strength, among all tested samples, was recorded for the composite filled with 10 wt.% of unmodified oak flour (69.1 MPa—10%U-OF). Additionally, higher values of flexural and impact strength, concerning pure BPA-based epoxy resin, were recorded for the composites with oak filler (respectively, flexural strength: 73.8 MPa—5%U-OF and 71.5 MPa—REF; impact strength: 15.82 kJ/m²—5%U-OF, 9.15 kJ/m²—REF). Epoxy composites with such mechanical properties might be considered as broadly understood construction materials. Moreover, samples containing wood flour as a filler exhibit better mechanical properties compared to those with peanut shell flour (tensile strength for samples containing post-mercerization filler: 48.04 MPa and 40.54 MPa; while post-silanization 53.53 MPa and 42.74 MPa for compositions containing 5 wt.% of wood and peanut shell flour, respectively). At the same time, it was found that increasing the weight share of flour of natural origin in both cases resulted in the deterioration of mechanical properties. Full article

To improve wood structure processing efficiency, a palletizing robot suitable for loading and unloading glued laminated timber (GLT) has been developed. The robot comprises a six-axis connecting rod mechanism and a sponge sucker as a grasping actuator, which can enable the intelligent automatic loading and unloading and palletizing operations for small-sized GLT. Matlab robotics was used to construct the kinematic model of the GLT loading and unloading robot. Based on Matlab and Monte Carlo methods, the robot workspace was simulated and analyzed to determine the scope of the robot workspace. Using the high-order quintic and sixtic polynomial curve interpolation method, the trajectory of wood structure parts in the process of loading and unloading operations was planned, respectively, under the two conditions of staying and not staying. Tests verified that the simulation results of the pose of the end-effector were consistent with the actual pose of the robot. The robot’s working range could be analyzed intuitively and effectively. The robot’s operation trajectory planning provides data support and a parameter basis for the automatic control and program design of a loading, unloading and palletizing robot. Full article

The exploitation of natural fibers to reinforce polymers is a promising practice. Thus, biocomposites have gained increased attention in automotive, construction, and agricultural sectors, among others. The present work reports the reinforcement of recycled high-density polyethylene (r-HDPE) with hemp fibers to afford composite materials as sustainable analogues to conventional wood/plastic composite (WPC) products. HDPE bottles (postconsumer waste) were used as r-HDPE and further reinforced by the addition of hemp fibers. For the synthetic part, thirteen composite materials with different filler concentrations (10–75% wt. in hemp fibers) using either Joncryl or polyethylene-grafted maleic anhydride (PE-g-MA) as compatibilizers were prepared via melt mixing. Materials with good integrity were obtained with a fiber load as high as 75% wt. The structural, thermal, mechanical, and antioxidant properties of the r-HDPE/hemp composites were evaluated using multiple complementary characterization techniques. Stereoscopic microscope images demonstrated the satisfactory dispersion of the hemp fibers into the polymeric matrix, while scanning electron microscopy microphotographs revealed an improved adhesion between the filler and the polymeric matrix in the presence of compatibilizers. The incorporation of hemp fibers contributed to the improvement of the elastic modulus of the composites (almost up to threefold increase). The results showed that as the hemp fiber content increased, the antioxidant properties as well as the degradability of the composites increased. It is noteworthy that composites containing 75% wt. hemp fibers neutralized 80% of 2,2-diphenyil-1-picrylhydrazyl radicals within 45 min (DPPH assay). In conclusion, the present research work demonstrates that thermally recycled HDPE reinforced with biomass fibers received from agricultural waste is a valid alternative for the preparation of commodity products with an eco-friendly character compared to conventional wood/plastic composites. Full article

The adoption of energy-efficient, clean, and safe cookstoves can improve the health of poor sub-Saharan households and reduce mortality and poverty, as identified in the United Nations’ Sustainable Development Goals (SDGs). Despite multiple interventions to increase the adoption of improved stoves and clean fuels, few interventions have borne fruit on a significant scale. The lack of adoption is shared in South Africa. (1) Background: The deleterious health hazards associated with flame-based cooking mainly affect women and children due to using portable and cheap paraffin (kerosene) cookstoves or self-constructed metal barrel wood stoves. A shift to improved cookstoves requires significant changes in users’ behaviour. Understanding and addressing the motivations for cookstove adoption and long-term use is critical for successfully implementing behavioural change campaigns. (2) Methods: A case study methodology is employed to evaluate the effectiveness of a behaviour-centred design (BCD) approach aimed at influencing cookstove-related motivations among low-income households in Dunoon, South Africa; the study gathers data via structured observations, co-creative workshops, and card-based choice questionnaires before and after a pilot intervention. (3) Results: The survey conducted before and after the abridged BCD intervention implementation in Dunoon indicates that the majority of touchpoints achieved significant success in influencing the selected cookstove-related motivations of the sampled households, further corroborated by an observed shift in household cookstove ownership patterns targeted by the intervention. (4) Conclusions: A BCD approach suggests possible methods for understanding and influencing the complex motivations determining cookstove use in a context similar to South Africa. The results suggest that linking pertinent motivations to a selected set of touchpoints as part of a cookstove-related campaign can influence cookstove-related motivations linked to the adoption of improved flame-based cookstoves in a localised South African low-income context. Full article