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A new structural typology of a Steel-Reinforced Wooden (SRW) purlin made of rectangular laminated wood and C-section type cold-formed steel is presented in this article. The steel C-section profile is fitted onto the wooden purlin so that both work together as a composite unit. Although the wooden sections are weaker and have a lower elastic modulus than the steel sections, the overall dimensions of the SRW purlins are no larger than the steel C-section purlin sizes. The SRW purlins also form lighter structures than either plain steel or wooden purlins and they therefore have lower CO2 emissions. In addition, lighter purlins reduce the load on the main structure, which in turn reduces the material needed for the main structure of the building. So, reinforcement of the wooden purlin with steel sections within certain areas notably improved performance when compared with ordinary single-material purlins. The use of the SRW purlins can, therefore, improve the overall sustainability of a building. The improvements were analyzed in terms of sustainability and lower weight, as a function of span length and design load. The behaviors of the single material purlins and the SRW purlin were also compared. Both material strength and deformation design criteria and their influence were studied using an analytical approach based on loading and span length. The simple, innovative, and reliable design procedure described in this study ensured compliance with all technical requirements. Moreover, the savings relating to material weight were evaluated, neutralizing the carbon footprint in all cases under analysis. [ABSTRACT FROM AUTHOR]

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A transversely isotropic structural model for wood, based on a polytope strength criterion, is proposed and deployed in the analysis of solid wood columna-capreoli A-trusses reproducing the geometry and connection details of those currently erected in the Aula Magna of the Monastery San Lorenzo ad Septimum in Aversa. The predictivity of the polytope strength criterion is assessed verifying its capability of identifying the closest crisis mode against experimental evidence from a simple flexural test, with minimal wood sacrifice. The model is employed in parametric optimization analyses to infer a design provision for the columna-capreoli connection which appears to be in reasonable agreement with the rule of the art empirically inferable from the observation of many samples of open-node King Post A-trusses belonging to the architectural heritage in Campania of historical and artistic value. A final discussion examines a perspective of extending these optimization analyses to the sustainability of the built environment.

Copyright of Thiasos Monografie is the property of Edizioni Quasar di Severino Tognon s.r.l. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction. The article considers the prerequisites for the development and application of new construction technology with the use of renewable natural resource — wood. The problem of providing construction with raw materials for production is relevant. Objectives of the research — determination of the main advantages and disadvantages of CLT-panels as a material used in load-bearing frames; feasibility of CLT-panels in relation to other traditional building materials; identification of the main technological features of construction production with the use of cross-glued panels technology, determination of the advantages of the technology; necessity of research activities on the construction material for updating the relevant building regulations; analysis of foreign experience in the field of construction of wood-based panels.Materials and methods. The review and analysis of domestic and foreign literature, scientific papers, normative documents, information sources on the basis of eLIBRARY.RU were performed. Comparison and systematization of the obtained data. Earlier studies were also taken as a basis.Results. On the basis of the conducted analysis of information sources the description of the main properties and characteristics, as well as production technology of CLT-panels is given; positive and negative sides of the material application, advantages of construction technology of building frames erection are determined. The comparative analysis of domestic and foreign experience in wooden house building is carried out. The problems of cross-glue panel technology development in Russia are defined.Conclusions. The results obtained through the conducted research determine the feasibility of using CLT-panels as a building material for load-bearing structures, characterized by the presence of a list of properties significant for the industry: environmental friendliness, renewability, high rates of work production, reduction in the cost of construction of objects due to the reduction of labour intensity of the construction process.

Introduction. A distinctive feature of CLT panels is the cross arrangement of planks (lamellae) in different layers of the board. Due to the anisotropy of wood, this design allows for high strength and stiffness in different directions of stress action, which has made this material one of the most promising to be studied in recent decades. This article examines the influence of the thickness of transverse and longitudinal layers in five-layer slabs of cross-glued timber boards, or CLT panels, on the deformation and distribution of the resulting normal and tangential stresses. The relevance of the work is conditioned by the necessity of obtaining calculated data to analyze changes in the strength characteristics of boards with different variations in the thickness of longitudinal and transverse layers in order to choose the most effective configuration of the board.Materials and methods. The studies were carried out by numerical methods using SCAD+ PC using FEM (Finite element method). At the same time, the three-dimensional finite elements are parallelepipeds. The design scheme is defined as a general-type system, whose deformations and its main unknowns are represented by linear displacements of nodal points along the X, Y, Z axes and rotations around these axes. As a design structure, a five-layer slab with cross-directed layers was chosen in such a way that the outer (1, 5) and central inner (3) layers are longitudinal, and the remaining inner (2, 4) are transverse. The simplified design scheme is a pivotally supported beam.Results. The results of the study and calculations made using SCAD+ were applied to make tables and graphs showing dependence of deflection, distribution of normal and tangential stresses on the thickness of transverse and longitudinal layers of the board.Conclusions. The obtained data allow us to evaluate the influence of thickness on deformability and stress distribution in five-layer CLT panels. The significance of the conducted research is in the expansion of scientific and technical knowledge base in the field of wooden structures.

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Over time, ancient wooden structures undergo challenges in structural integrity and stability, influenced by various environmental conditions such as temperature fluctuations and humidity variations. Maintenance and protection of this invaluable architectural heritage require precise performance predictions and optimisations. While existing research has delved deeply into performance prediction of wooden structures, it predominantly focuses on empirical observations and experimental analyses, with minimal establishment and validation of theoretical models. Moreover, extant methods for prediction and optimisation often overlook the strain variation of wood under different temperatures and the stochastic nature of environmental factors. This study seeks to address this research gap by investigating the relationship between strain in the grain direction of ancient wooden beams and temperature, and by formulating a comprehensive thermodynamic model. Additionally, a novel optimisation approach using the chicken swarm optimisation (CSO) algorithm has been introduced to further refine performance parameters of wooden structures. By integrating the theoretical model with the CSO, this research offers a novel perspective and methodology for the prediction and optimisation of the long-term performance of wooden structures. [ABSTRACT FROM AUTHOR]

Wooden rafter structures have undoubted advantages, which determine their wide application. The object of the study is triangular rafter structures. The purpose of the research is to find the dependence of force values in the elements of the studied structure on the magnitude of its lifting boom. The calculation of a triangular truss using the Maxwell - Cremona diagram is presented. The efficiency of the proposed method was estimated on the basis of a study of the structure of a wooden truss of the “scissors” type. The following pattern has been established: the change in the coordinates of the points (abscissas) of the force diagram is inversely proportional to the change in f . It is determined the area of rational values of the lift (roof slope) at which the values of internal forces tend to a minimum. It was revealed that the values of force increments in the truss elements at each step increase from 27% to 2 times when the roof slope de-creases. Based on the graphical analysis of the obtained data the range of effective values of the roof slope at which the forces in the elements of the truss take minimum values was found. Using a graphic method of determining the forces, it is possible to check variants of the roof slope in the search for a rational solution of the “scissor” type truss structure. It follows that the proposed method contributes to the choice of the most economical structural solutions.

Identification of flames to detect fires is hindered by the smoke generated from Chinese incense in traditional temples. Especially during holiday periods, smoke presents a large influence on the effectiveness of image-based flame identification. To have a deep understanding of the incense smoke impacting the flame outline, a series of tests were conducted to study the flame, varying incense smoke concentration and test time, respectively. It is found that when the flame is exposed to a thin incense smoke environment, nearly all the methods used for flame identification are effective. When the flame is surrounded by thick smoke, the flame image after treating by the self-adaptive image histogram equalization method is blurry. When the retinex algorithm is used for image treatment, the blue color near the flame is detected, which enlarges the flame area detection. The retinex algorithm can be used to obtain a clear flame outline even when the flame is exposed to a cloud of thick smoke. This is important for flame identification in the traditional Chinese temples where the thick smoke surrounds them, especially during national holiday periods. This work attempts to provide a potential method for flame identification and improve the safety level of historic buildings. [ABSTRACT FROM AUTHOR]

В данной статье приводится анализ армирования деревянных балок композитной арматурой с целью повышения несущей способности конструкции, а также для снижения трудозатрат на возведение зданий из деревянных элементов. В статье рассмотрены основные конструктивные и технологические аспекты армирования деревянных балок арматурой из композитных материалов, выявлены достоинства и недостатки данного типа усиления. Также детально разобраны составляющие балки такие как клеи и композитная арматура, озвучены основные требования к ним. Затронут вопрос влияния климата на совместную работу стеклопластиковой арматуры и древесины. Приведены доводы в пользу использования данного типа армирования деревянных конструкций. Выдвинут ряд задач, решив которые появится возможность отладить технологический процесс по производству клееных деревянных балок.

The flammability of wood largely limits the use of wooden structures in modern construction. Therefore, there is a need to protect the wooden structures of buildings and structures from fire danger. Ammophos-A, ammonium sulfate, expanded perliteб and epoxy were used to develop the fire-retardant surface coating. The experiments were carried out by changing the amount of one of these components in the composition, leaving the others constant. At the same time, fire hazard indicators were controlled parameters. In this way, the optimal ratios of the components of the flame-retardant composition were established, which were: 15:15:10:50 (wt.%), respectively, ammophos-A, ammonium sulfate, expanded perlite, epoxy resin, further designated flame retardant AS-143. The test parameters of structural samples treated with this flame retardant at a consumption of 400–500 g/m2 were: weight loss 4.0–5.0 %, flame burning time 11–18 s, flameless 19–23 s. The effectiveness of the flame retardant AS-143 was established in comparison with flame retardant No. 13, which, according to the weight loss of the samples, was 43.2 %. The essence of the results is explained by the correct selection of chemical compounds and their component ratio in the fire-retardant composition, which exhibit a synergistic character during the combustion of wooden structures. At the next stage, in addition to surface treatment of wooden structures, they were faced with fire-resistant plasterboard sheets. Fire tests were carried out under field conditions for 30 minutes, the results of which were: the length of flame propagation over the surface of the samples was 456– 678 mm; flame propagation speed 0.015–0.023 m/min. The data indicate that wooden structures treated in a combined way belong to group I of fire protection efficiency. These structures can be safely used in buildings and structures, especially with enclosing, attic, or attic types [ABSTRACT FROM AUTHOR]

Purpose. The main aim of the research is the study of the methodology of conducting engineering and technical reconnaissance and the implementation of structural and technological solutions for the project of the construction of a bridge crossing with a temporary bridge damaged as a result of hostilities. Methodology. The achievement of the set goal involves research and analysis of practical structural and technological solutions for construction works, restoration of bridge crossings with temporary bridges, as well as study and generalization of practical experience of implemented technological solutions of combining wooden typical structures with steel typical span structures. Findings. A generalization of the experience of conducting engineering and technical reconnaissance in construction areas, restoration of bridge crossings in de-occupied territories was generalized. The author revealed and clarified the general key stages of the implementation of technological solutions for the project of the construction of a bridge crossing with a temporary bridge damaged as a result of hostilities using a combination of steel inventory bridge structures with wooden bridge structures. Originality. For the first time, the author investigated the peculiarities of conducting engineering and technical reconnaissance in order to implement the obtained results in the relevant project documentation for the construction of a temporary bridge. The peculiarities of constructive and technological solutions with a rational combination of various materials and structures during the construction of temporary bridges, which ensure a long period of their operation, are considered. Practical value. The elements of the methodology of organization and carrying out engineering technical exploration of terrain, water obstacles, construction sites and the base of logistics and other measures will contribute to the quality preparation of project documentation for the construction of bridge crossings with temporary bridges. The application peculiarities of non-standard projects of conducting works and structural and technological solutions in the construction of temporary bridges have a number of technological advantages that make it possible to ensure effective restoration of the destroyed combat actions of the bridges in a short time. Some technological methods of combinations of wooden structures and elements with steel carriers of the roadway when building temporary car bridges increase their load capacity.

This article discusses the problems and technical issues related to the conservation and rehabilitation of historic wooden structures. Showing the history of wooden construction in Europe and Poland, it analyzes the technical solutions used for the timber structure of buildings. The author highlights the leading technical and conservation issues arising from the principles of conservation of wooden heritage buildings, taking into account the role, importance, and proper implementation of diagnostics preceding conservation engineering activities. The article discusses interdisciplinary diagnostics developed by the author, an original method for assessing the revitalization capability of a historical building, which analyzes non-technical issues, including those relevant to conservation, in addition to the technical aspects of assessing the technical condition of a building. Based on engineering practice, problems and technical issues that often occur in the conservation process of wooden buildings, as well as in the broader process of their revitalization, are presented. They concern various engineering activities that must be implemented in this process according to the principles discussed. [ABSTRACT FROM AUTHOR]

Copyright of Space & Form / Przestrzeń i FORMA is the property of West Pomeranian University of Technology, Department of Architecture & Urban Planning and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wood has a long history of being used as a valuable resource when it comes to building materials. Due to various external factors, in particular the weather, wood is liable to progressive damage over time, which negatively impacts the endurance of wooden structures. Damage assessment is key in understanding, as well as in effectively mitigating, problems that wooden structures are likely to face. The use of a classification system, via deep learning, can potentially reduce the probability of damage in engineering projects reliant on wood. The present study employed a transfer learning technique, to achieve greater accuracy, and instead of training a model from scratch, to determine the likelihood of risks to wooden structures prior to project commencement. Pretrained MobileNet_V2, Inception_V3, and ResNet_V2_50 models were used to customize and initialize weights. A separate set of images, not shown to the trained model, was used to examine the robustness of the models. The three models were compared in their abilities to assess the possibilities and types of damage. Results revealed that all three models achieve performance rates of similar reliability. However, when considering the loss ratios in regard to efficiency, it became apparent that the multi-layered MobileNet_V2 classifier stood out as the most effective of the pre-trained deep convolutional neural network (CNN) models.

Identification of flames to detect fires is hindered by the smoke generated from Chinese incense in traditional temples. Especially during holiday periods, smoke presents a large influence on the effectiveness of image-based flame identification. To have a deep understanding of the incense smoke impacting the flame outline, a series of tests were conducted to study the flame, varying incense smoke concentration and test time, respectively. It is found that when the flame is exposed to a thin incense smoke environment, nearly all the methods used for flame identification are effective. When the flame is surrounded by thick smoke, the flame image after treating by the self-adaptive image histogram equalization method is blurry. When the retinex algorithm is used for image treatment, the blue color near the flame is detected, which enlarges the flame area detection. The retinex algorithm can be used to obtain a clear flame outline even when the flame is exposed to a cloud of thick smoke. This is important for flame identification in the traditional Chinese temples where the thick smoke surrounds them, especially during national holiday periods. This work attempts to provide a potential method for flame identification and improve the safety level of historic buildings.

The article contains information on the nature of the parameters involved in the calculation of the fire resistance of wood structures, widely used in the construction sector, and the standards, recommendations and nomograms used in the determination. When deter-mining all forms of states of strength of boarding houses, the main factors affecting their limit were considered, and the calculation rules were indicated. Thermal engineering issues of struc-tures - determining the temperature distribution along the very edge of the elements, heating the non-carbon part of the muscle, as well as determining the speed and depth of carbon. At the same time, for curved elements, two decomposition schemes are given, depending on the amount of torque and the ratio of the width of forces in the dash, as well as the ratio of the length of these trails to height. The description of the changes and the procedure for determining the corres-ponding parameters, accompanied by the destruction and loss of strength of the elements in the direction of compression of the line from the influence of flame, are shown. Here are some examples of how to calculate the fire resistance limits of structures or individual elements that are subject to compression and bending. The reports used SniP standards for fire resistance of wood structures and nomograms compiled by SNISK. [ABSTRACT FROM AUTHOR]

Copyright of Virtual Archaeology Review is the property of Virtual Archaeology Review and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of State & Society / Państwo i Społeczeństwo is the property of Andrzej Frycz Modrzewski Krakow University, AFM Publishing Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Wood Industry / Drvna Industrija is the property of Drvna Industrija and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Findings of structures remains discovered during excavations on Medieval Mongolian Sites in Eastern Trans-Baikal Region were summarized in the article. They were excavated during exploration of Alestui Mansion, at Khirkhira fortress, as well as at Konduy town site. The similar findings at Sutai Mansion in Buryatia, at Den-Terek fortress in Tuva, Karakorum, Shangdu, at Avraga fortress in Mongolia can be drawn on for comparison. In addition to traditional archaeological methods of the material investigation, an anatomical study of wood has been accomplished at Federal Scientific Center of the East Asia Terrestrial Biodiversity FEBRAS (Vladivostok). The study results evidence that some of samples collected belongs to Pinaceae, and one of them is the wood of Larix gmelinii or Dahurian Larch, vegetated in this region. Despite of rarity and fragmentariness of this kind of sources on Medieval sites of Central Asia and Far East, it was found out that the wood of local origin was utilized by the Mongols for monumental objects construction. This research is only a part of work on construction materials investigation of Medieval Mongolian Archaeological Culture.

Copyright of Journal of Shanghai University / Shanghai Daxue Xuebao is the property of Journal of Shanghai University (Natural Sciences) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: The paper addresses the issue of using regression equations to determine the residual operating life of structures made of wood of various species in high humidity conditions. Purpose of the study: The study is aimed at deriving general equations for calculation of the ultimate life of wooden structures using univariate regression equations for subsequent calculation of the residual operating life (option 1), or equations for immediate calculation of the residual operating life (option 2). Methods: Univariate regression equations are used: linear, logarithmic, seconddegree polynomial, power, exponential, natural exponential, and hyperbolic. Results: The authors derive general equations for calculation of the ultimate life of wooden structures for subsequent calculation of the residual operating life (option 1), and equations for immediate calculation of the residual operating life (option 2), presenting advantages and disadvantages of both options. They propose an algorithm to process the obtained results in case the calculation is carried out using several equations at once. The authors also present an example of calculating the residual operating life using the second option. Discussion: Based on the proposed relationships, it is possible to determine the residual operating life of any wooden structures under any operating conditions.

The article deals with the long-discussed problem of the so-called tent-like churches in Russian architecture (of the XVI to the XVII centuries), with all existing theories of their origin being considered, presenting two opposed views tentatively termed the isolationist and the internationalist ones, not excluding those, who tried to go away from this strict opposition. An attempt at the radical solution that rejects a traditionally accepted notion of this type’s originality and uniqueness is made, with a proposal to take it instead for quite an ordinary variation of the eight-sided cloister vaults wide-spread in medieval architecture, that at times could be turned into these tents by simply straightening their otherwise curved constructions thus creating some kind of a pyramid. If properly investigated with all necessary parallels in Western architecture taken into account, even a search for the deeper symbolic meaning of this construction type (be that a holy place for the civil power representative or an allusion to St. Sepulchre) may become dispensable; this approach permits to treat instead the phenomenon as an incidental one caused by the mere formal and technical experiments and to a certain extent explicable by the intrusion of the Italian architects in the medieval Grand Duchy of Moscow.

To have a deep understanding of influence of woodgrain orientation on the upward flame spread performance, a series of tests were conducted to obtain the profile of mass loss rate (MLR), flame spread rate (FSR), total burning duration (TBD), and the maximum flame characteristic length (MFL) by using a traditional flame spreading measurement facility. The woodgrain orientation of samples tested in the current work are horizontal (H), vertical (V), and slanting (S). During the tests, a series of six 2 cm-long 10 cm-wide wood chips were uniformly installed on a vertical sample holder. The distance of air-gap differed from 1.0 cm to 3.0 cm and the thickness of wood chips varied from 1 mm to 4 mm. It is found that flame spread over discrete solid fuels depends on the generation rate of pyrolysis gas and direction of gas-flow, which is highly differed by the woodgrain orientation with respect to the wooden chips. The charring rate of samples imposed a strong effect on the flame spread performance. The a-MLR of three kinds of woodgrain are ranked as V > S > H. The FSR are ranked in general as H > V > S. The thickness of the samples imposed a larger effect on the TBD comparing with wood grains orientation. The TBD are ranked as S > V > H. The results of MFL indicate that as the thickness of the sample increases, MFL of samples performed with the H woodgrain is reduced greatly. However, both S and V woodgrain show a small effect on the MFL. It hopes to provide a deep understanding of flame spreading performance over wooden structures.

Copyright of Iranian Journal of Wood & Paper Science Research is the property of Research Institute of Forests & Rangelands and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Builder (1896-0642) is the property of PWB MEDIA Zdzieblowski sp.j. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wood, a time-honored construction material prized for its exceptional properties, has been in use for millennia. Its enduring popularity is attributed to its remarkable strength, aesthetic appeal, and favorable environmental footprint. However, wooden structures are susceptible to various defects and imperfections that pose threats to their structural integrity, durability, and safety. These issues encompass knots, cracks, warping, twisting, decay, insect infestations, and more, all of which, if left unaddressed, can culminate in structural failures. Thus, a comprehensive strategy involving inspection, maintenance, and remediation is indispensable for safeguarding wooden structures. Traditional manual inspections, while effective, are characterized by their resource-intensive nature, entailing significant time and cost investments. This study presents a pioneering approach that leverages Convolutional Neural Networks (CNNs) and Image Processing techniques to revolutionize the assessment of damage in wooden structures using digital imagery. Initially, CNNs are employed to categorize images into three fundamental classes: cracks, knots, and undamaged sections. Subsequently, Image Processing techniques are harnessed to compute precise characteristics of these defects, including parameters such as crack length, width, angle, and the extent of the defective area within knots. The Inception-ResNet-V2 pre-trained model is utilized, fine-tuned and validated with a robust dataset comprising 9000 wooden defect images, evenly distributed across the three aforementioned categories. A prudent division allocates 70% of the dataset for model training, with the remaining 30% reserved for validation. Following successful training, the model demonstrates an impressive overall accuracy of 92% when classifying an independent test set comprising 100 new images. To illustrate the model's performance, two images from each damage category are selected and tested to compute the characteristics of the defects. The quantification error for crack angle is only 0.15%, while it is 0.99% for crack length, and 2% for crack width, demonstrating the high performance of the model. The practical implications of this work are profound. By automating defect assessment in wooden structures, our approach offers significant advantages to industry professionals. It expedites inspections, reduces labor costs, and enhances the accuracy of defect quantification. • Use of CNN and Image Processing techniques to automatically assess the type and extent of damage in wooden structures. • IP is used to compute characteristics, such as crack length, width, angle, and defective area of knots. • Inception-Resnet-V2 is trained and validated using a dataset of 9000 images of defects. • Model achieves an overall accuracy of 92% when classifying testing images. • Crack quantification errors are 0.15% (angle), 0.99% (length), and 2% (width), demonstrating the performance of the model. [ABSTRACT FROM AUTHOR]

Purpose. From 01.02.2018, the new state standards DBN B.2.6-161:2017 were introduced into the wooden structures design practice. They replace the recently prepared codes DBN B.2.6-161:2010, which, in turn, were elaborated to replace the SNiP II-25-80. The author of this publication would like to draw the attention of developers and potential users of the codes DBN B.2.6-161:2017 to the points that are not entirely clear, which at first reading caused him certain difficulties in terms of their practical use. Methodology. The practical experience accumulated by the author in the use of normative literature in educational practice, as well as the available experience during laboratory studies with students, made it possible to estimate the recently introduced codes DBN B.2.6-161:2017 from a practical point of view. Findings. In general, the new codes, recently introduced into design practice, are progressive both in their content and in terms of their use in construction practice. However, the existing problem areas in these standards, which are considered in this publication, in our opinion, can significantly limit the possibility of their wide practical application. Originality. The analysis of recently introduced new standard was carried out by the author of the publication not only in terms of assessing quality requirements and recommendations, but also in terms of the quantitative aspect of the issue. Practical value. The author’s experience in calculating simple elements and basic types of connections according to the new codes DBN B.2.6-161:2017 indicates that the bearing capacity determined for various cases is lower on average by 1.5 – 3 times than according to the previous codes SNiP II-25-80. From a practical point of view, this revealed discrepancy means that the already constructed structures may require some reinforcement or reconstruction, and new designed structures should have large bearing sections of the elements and, accordingly, large bearing capacity and weight.

This paper presents the results of preliminary tests for estimating the modulus of elasticity of wooden beams from firs reinforced with PBO fiber mesh. The tests were carried out in the Materials Strength Laboratory at the Kielce University of Technology in Kielce, Poland with PN-EN 408: 2004. The wooden elements were subjected to a four-point bending test with the aim of estimating the elastic modulus when bending, assuming the loading velocities of the loading forces of 5 mm / min. The obtained results show a significant increase in the load-bearing capacity of beams reinforced with PBO mesh.

With full respect for the principles of linking wood and conservation project Eldar pine because having good mechanical properties and availability of a wood structure in the form of pavilions chose alcove to the octagon without internal column with computer software Sketch up of Alborz research center with trees and landscaping of the complex was built. In making these structures all stages of the preparation of the wooden parts of drying are quite principled and dried in the open air during the six months were roof wood structure with the use of Eldar pine just Lambe was made in setting up the ceiling of solar connection on an octagonal timber wood using mortise and tenon mode and auxiliary metal was used. Sliding windows can be made to occupy less space. After completion of the period of three months to review the different pieces in different parts of the structure and measurements of physical densities, shrinkage and swelling and mechanical testing of hardness and impact resistance and protection review different parts of the fungal infection and decay structures was investigated. Since shortly after the beginning of the measure is going to change in the early stages of measuring statistically Darnbvdh but in the last stage of a decrease in density of about 5% and reduce the hardness of about 8% were signs of shrinkage and swelling in various parts of it to be seen.

The paper is a review of the literature on the strengthening of wooden structures. The strengthening methods are classified according to their purpose and specifics. The article deals with both traditional methods commonly used and modern methods involving the use of composite materials. The paper also includes description of studies on various strengthening methods as well as the presentation of their results. The author also refers to the causes of the loss of load bearing capacity, causes of wood degradation and wooden structures durability in relation to operating conditions.

St. Peter’s Basilica inside the Royal Palace of Palermo, known as the Palatina Chapel, is one of the most popular medieval monuments in Sicily. Built between 1130 and 1163, it contains interesting wooden framings that represent both bearing and finishing structures.Studies about the Arab-Norman church have often concentrated on the very rich and suggestive decorative mosaic apparatus of walls and floorings, as well as the pictorial cycle of wooden ceilings. Knowledge about the constructive techniques adopted and, in particular, about the realization of the coverings, is very limited: there are wooden floors built at different levels, vaults and wooden ceilings and among these is the portion that covers the main nave, housing the muqarnas decorations.The fortunate coincidence of the restoration building yard made it possible to gain precious knowledge of this extraordinary wooden structure, also through a laser scanning survey of a significant area of the wooden ceiling, performed with a low range device. The collected data adequately represent the geometry and the state of conservation of the ceiling and have been used to develop a spatial and geometrical analysis of the muqarnas and relate it to the structural layout.The survey of the internal and external sides of the covering enabled us to investigate further the materials and constructive techniques employed in this ancient wooden ceiling. At the same time, we were also able to document the original structural system and the completion parts, its conservation status and the interventions and modifications it has undergone through many centuries.

Wooden structures made of felled trees are used in forested slopes as protection structures against rockfall. A model based on the Discrete Element Method is developed to analyse their response to normal impacts of blocks. The interaction between the blocks and the stems and the stem response are explicitly integrated. After the model calibration using impact tests, a wide range of impact scenarii representative of real configurations is explored. The influence of three parameters (stem diameter, impact velocity and block diameter) is analysed. Three impact types were identified for different ratios R D between the block and stem diameters. For small R D , the impact is limited to a brief contact. For intermediate R D , successive contacts of similar duration are observed. After the last contact, the block is sent back with a large velocity. For large R D , two contacts are observed. The second contact can be assimilated to a quasi-static loading of the stem. In addition, structure damage increases for increasing R D ranging from almost no damage for the first impact type to rupture of the stem for the third type. The largest R D associated with the first impact type is the target configuration that favours block energy decrease and limits structure damage. [ABSTRACT FROM AUTHOR]

Recently, many roof fires have occured in Europe due to the presence of a chimney. Since also certified chimneys were involved in the fires, chimneys producers have attempted to propose some solutions. However, these latter may sometimes not be effective, especially if the chimney operating conditions are more severe than those in the chimney certification procedure. Consequently, given the relevance of the problem, the scientific community was asked to identify the causes of the fires, and many studies presented in the literature have shown some points to be taken into account when designing and testing a chimney. Since heat transfer at chimney-roof penetration depends on many variables, recently, it was proposed to limit the temperature at this point by means of a device. The device should limit the temperature in very thick and insulated roofs, and in any chimney operating condition, that is, in normal chimney operating conditions and during soot fire events. Such a device is called CEIL and its features were identified in a numerical study presented in the literature. Differently from the device in the market, the CEIL device is made of conductive elements and insulating materials. The function of the insulating layer is the limitation of the heat flux from the chimney to the roof, whereas the function of the conductive elements is the facilitation of the heat transfer from the device to the surrounding. In other words, the conductive elements act like fins that dissipate heat to the ambient. Given that no experimental test was performed, this paper presents the results of an experimental campaign performed to assess the efficacy of the CEIL device and to investigate aspects not taken into account in the preliminary numerical investigation. The experimental campaign has taken into account the most critical chimney operating conditions identified in the literature and it has consisted into three phases. Firstly, it has been investigated whether a device of fixed dimension can effectively be installed in any roof. In the second phase it has been investigated whether a conductive element installed in the clearance can actually limit the roof temperature in very critical operating conditions represented by high exhaust gas temperature in the chimney and small air infiltration in the materials at the chimney-roof penetration. Finally, the effectiveness of a device 200 mm thick in height and 100 mm thick in width has been assessed in different operating conditions. Results show that the coupling of an appropriate number of conductive elements and insulating layers can limit the roof temperature effectively. For example, the presence of a conductive element reduces the roof temperature from 140°C to 70 ∘ C with a device 5 cm thick when the exhaust gas temperature is 500 ∘ C . A device made of an insulating layer 100 mm width and two conductive elements keeps the roof temperature at 61 ∘ C when the exhaust gas temperature is maintained at 650 ∘ C until the achievement of the steady condition and it is risen at 970 ∘ C for 30 min. [ABSTRACT FROM AUTHOR]

The article deals with the long-discussed problem of the so-called tent-like churches in Russian architecture (of the XVI to the XVII centuries), with all existing theories of their origin being considered, presenting two opposed views tentatively termed the isolationist and the internationalist ones, not excluding those, who tried to go away from this strict opposition. An attempt at the radical solution that rejects a traditionally accepted notion of this type’s originality and uniqueness is made, with a proposal to take it instead for quite an ordinary variation of the eight-sided cloister vaults wide-spread in medieval architecture, that at times could be turned into these tents by simply straightening their otherwise curved constructions thus creating some kind of a pyramid. If properly investigated with all necessary parallels in Western architecture taken into account, even a search for the deeper symbolic meaning of this construction type (be that a holy place for the civil power representative or an allusion to St. Sepulchre) may become dispensable; this approach permits to treat instead the phenomenon as an incidental one caused by the mere formal and technical experiments and to a certain extent explicable by the intrusion of the Italian architects in the medieval Grand Duchy of Moscow. [ABSTRACT FROM AUTHOR]