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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.)

Abstract This paper presents the current state of conservation of historic roof churches located in the Żuławy of Gdańsk (Poland). It also describes the architecture of these temples, the region itself and old carpentry techniques for constructing roof trusses. Interdisciplinary tests were carried out in six churches. The geometry of the load bearing structures, the moisture content and the carpentry technique were specified. The field survey also included visual inspections and non-destructive testing of timber structural elements of the roof constructions. The ground penetrating radar and ultrasonic testing methods were used to assess the structure and extent of the damage to the timber elements. The interdisciplinary research presented in this article is important in the planning of historic buildings conservation works and it might be applied to other timber structures.

This paper presents the current state of conservation of historic roof churches located in the Żuławy of Gdańsk (Poland). It also describes the architecture of these temples, the region itself and old carpentry techniques for constructing roof trusses. Interdisciplinary tests were carried out in six churches. The geometry of the load bearing structures, the moisture content and the carpentry technique were specified. The field survey also included visual inspections and non-destructive testing of timber structural elements of the roof constructions. The ground penetrating radar and ultrasonic testing methods were used to assess the structure and extent of the damage to the timber elements. The interdisciplinary research presented in this article is important in the planning of historic buildings conservation works and it might be applied to other timber structures. [ABSTRACT FROM AUTHOR]

The wooden dome that covers the Hall of Ambassadors of the Alcazar of Seville (1427 AD) can be considered an exceptional architectural and constructive element in which visible ornamentation and underlying structure are inextricably linked. This article proposes a methodological approach integrating different disciplines (engineering, architecture, and history) to discern comprehensively the genesis and the in-depth constructive and structural performance of this outstanding architectural heritage. Thus, based on historical references on the construction of wooden domes together with the knowledge that the carpentry guild applied at that time, a detailed geometric and constructive analysis of the dome has enabled us to establish that its construction must have been carried out through the prefabrication of sectors. In addition, a structural model has been generated, with which, through various hypotheses, using a nonlinear finite-element analysis its mechanical behavior can be understood. The profusion of noggings, which follow the strict geometry derived from patterns of 10-point stars, plays a fundamental role in the stability and resistance of the set. Furthermore, it has been verified that an additional roof structure should always have been located over the dome and the tie rod bracing, made of steel nowadays, should always have existed and is located in its most optimal position. [ABSTRACT FROM AUTHOR]

The article focuses on the oldest surviving I-type portico houses located in the Vistula Delta, which were built in the 17th and 18th centuries. The study describes the houses' origins, structure, details of roof structures and technical condition, and it also includes numerical modelling of a roof truss and its mechanical analysis. Numerical models of the roof trusses are defined and analysed by means of the finite element method. Global sensitivity analysis with the use of the polynomial chaos expansion method is used to study the influence of uncertainties in material properties of wood, such as Young's modulus and the friction coefficient, and also the beam cross-sectional height in the output of the numerical model of the structure. The outcomes show that the uncertainty of beam height exerts the dominating influence on the maximum deflection of the roof truss, hence accurate measurements of geometry are of great importance in the planning of conservation and renovation of such historic structures. [ABSTRACT FROM AUTHOR]

A modern, environmentally friendly urban lifestyle requires paying attention to landscaping and green areas. The scarcity of free land in cities and the high price of land require the combination of greenery with buildings—both vertically and horizontally. The developed green technology for construction brings together computer numerical control (CNC) processing of supporting structures and prefabricated solid planting blocks made of concrete composite. The timber structures are fixed together using traditional carpentry joints. The details, which will be manufactured in the factory using CNC processing at a controlled temperature and humidity corresponding to indoor conditions, can be easily assembled on the construction site. The high bending strength but good elasticity and connections of carpentry joints endow the structure with good properties in a non-controllable environment. By combining CNC-processed wooden structures with concrete technology as substrate composites, labor-intensive manual work in landscaping and gardening will be reduced in the future. The novel material-hardening substrate composite material uses only the residues as the raw materials. [ABSTRACT FROM AUTHOR]

Copyright of Transsylvania Nostra is the property of Transsylvania Nostra Foundation 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.)

Abstract This paper summarises the current state of knowledge related to scarf and splice carpentry joints in flexural elements, also providing some examples of tensile joints. Descriptions and characteristics of these types of joints found in historical buildings are presented. In addition, issues related to forming carpentry joints in historic and heritage structures are discussed. Next, analyses and studies of flexural elements as well as selected examples of tensile joints described in the literature are presented. It is worth noting that authors of vast majority of the publications cited draw attention to the need for further research in this area. They acknowledge that existing descriptions are incomplete and insufficient for bringing about precise understanding and correct description of the static behaviour of these joints. Knowledge about designing and assessing static behaviour of existing carpentry joints is an important issue and is necessary to properly design and strengthen existing joints in historical timber structures.

The paper presents the analysis of the dovetail joint, typical for rafter-collar-beam connection, under tension. The development of wooden structures with these joints, and the general principles of their static work are shortly presented. The results of research on: functional joint with proper contact surfaces, joint with loosened contact, and joint with reinforcement were presented. The results confirm that the dovetail joint can transfer tensile forces, some of which are transferred by the wooden dowel. Small loosenings between connected elements does not decrease the load-capacity or stiffness of the joint. The reinforcement changed the static behavior of the joint, as expected. The obtained results present a certain picture of the static behavior of the analyzed connection in the case of tension forces, and the drawn conclusions may be useful for engineers and conservators in design and implementation practice when working with historic wooden structures. • Dovetail joint between rafter and collar beam is able to transfer tensile forces. • Small loosening does not decrease the capacity or stiffness of the joint. • In dovetail joint under tension some force is transferred by the wooden dowel. • Reinforcement change the character of static behavior of the joint. [ABSTRACT FROM AUTHOR]

Timber frame structures have a long and rich tradition. In addition to their functional and structural value, they are important elements of the cultural landscape. At the turn of the 21st century, concern for nature, resulting from the threat of environmental degradation, contributed to a growing interest in wooden constructions. For these reasons, we have observed the erection of buildings with wooden frame structures in many countries around the world. This trend contributed to the rapid development of wooden structures, new technologies, and innovative architectural solutions. The conducted research mainly focused on the joints used in their construction, as well as their perception. From among many examples, some original and innovative solutions were selected and analyzed. Their creators are famous architects: Renzo Piano, Imre Makovecz, Jürgen Meyer, Kengo Kuma, and Shigeru Ban. The objects presented in this article are distinguished by the originality of their form and by the fact that they are clearly inspired by vernacular architecture. Crucial elements of these objects, such as wooden, steel, and hybrid connections, are analyzed in this article. Because they are intentionally exposed, they play an important aesthetic role in addition to a structural one.

Historic arcaded houses of the delta of the Vistula were the subject of great interest of many researchers, but their work was focused mainly on historical-architectural aspects. There are no publications which would focus on details and comprehensive analyses of construction systems for this group of historic buildings. The article is the result of field research, archival query and calculations made by the author. The paper analyses the rafter framing constructions of the preserved arcaded houses of type III. The author has prepared a list of construction elements of roofs, carpentry joints, rafter inclination angles and described the state of preservation of roof structure. The paper also includes calculations of the average volume construction material of the roof structure per square meter of roof slope plan. [ABSTRACT FROM AUTHOR]

Highlights • Stresses distribution in carpentry joints is analysed based on FEM models. • Stress in the saddle notch connection is less sensitive to the boundary conditions. • Uncertainty of material and friction coefficient are propagated in the model. • High variance of the output is observed considering even only one kind of wood. • Uncertainty of material has a strong effect on the principal stress. Abstract The paper presents the results of numerical analysis performed on historical, traditional carpentry corner log joints of two basic topologies: the short-corner dovetail connection and the saddle notch connection. These types of carpentry joints are commonly used in currently preserved objects of wooden architecture. All connections have been modelled in pinewood, which has been defined in the Finite Element software MSC.Marc/Mentat as an orthotropic material. The numerical calculations have been carried out for two types of connections with two different boundary conditions and load types. The contact phenomenon between the individual elements of the connections has been taken into account. The main purpose of the research is to select the most damage-resistant type of connection and to determine the stress distributions on the contact surfaces, which demines the damage areas. However, a lot of uncertainties appear in the studied models, e.g. due to the natural variability of the material properties of wood and the uncertainty of friction coefficient. Therefore the uncertainty quantification and global sensitivity analysis has been performed in order to include these uncertainties and study their effect on variation of the mechanical response of the connections. A regression-based non-intrusive polynomial chaos expansion method has been employed to complete the task. The state-of-the-art knowledge about the damage-prone zones in the considered connections is immensely important since many wooden buildings, mostly historical, require maintenance, renovation and the reinforcement of existing, especially historical elements. On the contrary, there are not many results of related research published yet. [ABSTRACT FROM AUTHOR]

The paper presents the results of concept design for modelling, designing and producing long span portal frames and constructing buildings with them. Ordinary portal frames of steel structure are not suitable in many cases for a variety of reasons. They are heavy and very fragile to transport, are not fire resistant, are present special difficulties in use because of possible corrosion and are always not satisfactory architecturally. Wood-steel assemblies such as flitch beams are also complicated because of possible condensed water on metal and fasteners. Constructions using GLULAM and CLT (especially in the last decade) show rising trend. Timber has very many good properties as a building material if we know or remind ourselves of the skills how to handle it. The biggest enemy of wood and the reason for decay is moisture. All structures and finishing materials need very careful and qualified design to avoid collection of water on surfaces and consequent increasing moisture content. This paper describes a method appropriate for the 21st century of how to design portal frames of GLULAM and CLT panels and construct of them without metallic fasteners. [ABSTRACT FROM AUTHOR]

The European rules of timber structural design do not include distinct rules on carpentry joints. As a contribution towards filling this gap, this study into the existing knowledge of the most commonly used carpentry joint, the single-step joint, is performed. The design rules of three European countries and the latest developments on the topic are discussed. This study shows that the knowledge of expected stress distributions as a consequence of the geometric shape is important to achieve the intended reliability level for joints. The investigation indicates that further research on the combination of shear and compression forces is necessary to improve and include in the design rules in Eurocode 5. [ABSTRACT FROM PUBLISHER]

In European seismic areas timber structures are found as building frames, in combination with masonry infills, in bridges, but most frequently in roof structures and floor slabs of traditional buildings. Seismic strengthening of existing structures should provide a well-defined and simple path to seismic forces, maintain timber members elastic, and develop as much as possible the post-elastic behaviour of joints. Provisions must be adopted to avoid sudden loss of capacity and brittle failure, and to foster ductility. Different criteria for seismic strengthening of floor slabs and of carpentry joints are presented. [ABSTRACT FROM AUTHOR]

Joints play a major role in the structural behavior of old timber frames (Descamps et al., 2014) [1] . Current standards mainly focus on modern dowel-type joints and usually provide little guidance (with the exception of German and Swiss NAs) to designers regarding traditional joints. With few exceptions, see e.g. [2–4] , most of the research undertaken today is focused on the reinforcement of dowel-type connections. When considering old carpentry joints, it is neither realistic nor useful to try to describe the behavior of each and every type of joint. The discussion here is not an extra attempt to classify or compare joint configurations (Gerner, 2012) [5,6] , (Seike, 1977) [7] . Despite the existence of some classification rules which define different types of carpentry joints, their applicability becomes difficult. This is due to the differences in the way joints are fashioned depending, on the geographical location and their age. In view of this, it is mandatory to check the relevance of the calculations as a first step. A limited number of carpentry joints, along with some calculation rules and possible strengthening techniques are presented here. [ABSTRACT FROM AUTHOR]

Blätter für Winkel‐ und Kreuzverbindungen sind wesentliche Bestandteile vieler zimmermannsmäßig errichteter Holztragwerke in Mitteleuropa. Die Anwendung dieser Verbindungen als statisch tragende Anschlüsse nach EN 1995‐1‐1 bedarf der Kenntnis ihrer Tragfähigkeit und ihres Verformungsverhaltens. In der Normung und Literatur fehlen hierzu Angaben. Im vorliegenden Beitrag werden daher die Tragfähigkeit und das Verformungsverhalten von druckbeanspruchten Blättern (Winkelverbindungen, hier: Weißschwänze und Überblattungen) behandelt. Die Auswertung der Ergebnisse von 92 zerstörenden Prüfungen werden vorgestellt. Sowohl für die Bemessung dieser Verbindungen als auch für die Ermittlung der Federsteifigkeiten werden Berechnungsvorschläge angeführt. Load‐bearing capacity and load‐bearing behaviour of lap joints loaded in compression Angle and cross joints using laps are important members of a lot of roof structures erected by carpenters in central europe. The structural usage of these joints demands the knowledge of their load‐bearing capacity and behaviour according to EN 1995‐1‐1. Therefore codes and literature lack information. This contribution deals with the load‐bearing capacity and behaviour of lap joints (as angle joints, here: dovetail lap joints and halved joints) loaded in compression. 92 tests were performed and analysed. Both proposals for the design and for the determination of the stiffnesses of these joints are given here. [ABSTRACT FROM AUTHOR]

Kämme für Kreuz‐ und Eckverbindungen sind wesentliche Bestandteile nahezu jedes zimmermannsmäßig errichteten Holztragwerks in Mitteleuropa. Die Anwendung dieser Verbindungen als statisch tragende Anschlüsse nach EN 1995‐1‐1 bedarf der Kenntnis der mechanischen Kenngrößen. Umso erstaunlicher ist es, dass in der Literatur bislang Angaben zur Tragfähigkeit und insbesondere zum Verformungsverhalten fehlen. In diesem Beitrag werden 26 zerstörende Prüfungen an unterschiedlichen Kammverbindungen und deren Auswertungen vorgestellt. Sowohl für die Bemessung dieser Verbindungen als auch für die Ermittlung der Steifigkeiten – abgeleitet aus dem Verformungsverhalten – werden Berechnungsvorschläge angegeben. Load‐bearing capacity and load‐bearing behaviour of notched joints Cross and corner joints using notches are important members of almost every roof structure erected by carpenters in central europe. The structural usage of these joints demands the knowledge of their load‐bearing capacity and behaviour according to EN 1995‐1‐1. It's even more astonishing, that therefore codes and literature lack information. This contribution deals with 26 tests of different notched joints and their results. Both proposals for the design and for the determination of the stiffnesses of these joints are given here. [ABSTRACT FROM AUTHOR]

Blockhaus structural systems are obtained by assembling multiple timber logs able to interact with each other by means of simple mechanisms (e.g. contacts, tongues and grooves, and carpentry joints, also referred to as ‘corner’ joints). Although these systems have ancient origins, the structural behaviour of Blockhaus systems under well-defined loading and boundary conditions is still complex to predict. The paper focuses on the assessment of the typical buckling behaviour and resistance of in-plane compressed timber log-walls. The effects of various mechanical and geometrical aspects such as in-plane rigid inter-storey floors, load eccentricities, different types of lateral restraints, openings (e.g. doors or windows) or additional metal stiffeners, are investigated by means of full-scale buckling experiments. Results are then critically discussed and preliminarily assessed via analytical formulations taken from classical theory of plate buckling and column buckling. Although further advanced studies are required for the development of a generalized buckling design method, it is shown that several mechanical and geometrical aspects should be properly taken into account to correctly predict the structural capacity of Blockhaus systems under in-plane compression. [ABSTRACT FROM AUTHOR]

In the scope of European Cooperation in Science and Technology–Wood Science for Conservation of Cultural Heritage (COST IE0601–WoodCultHer) (available athttp://www.woodculther.org) it was agreed to produce Guidelines for the Assessment of Historic Timber Structures, covering the principles and possible approaches for the safety assessment of old timber structures of historical relevance that could be used as the basis for possible European Standards, as discussed with CEN/TC346 (Conservation of Cultural Heritage). This approach was targeted at all those concerned with the conservation of heritage buildings. These guidelines should also help decision-making regarding the need for immediate safety measures. The aim is to guarantee that inspection and assessment measures provide the necessary data for historical analysis, structural safety assessment, and planning of intervention works, while having minimal impact on the building fabric (the original materials, structural systems, and techniques).This article provides information on the criteria to be used in the assessment of load-bearing timber structures in heritage buildings. It covers the preliminary assessment (desk survey, preliminary visual survey, measured survey, structural analysis, and preliminary report), as well as the detailed survey of timbers (with a special emphasis on visual strength grading on site) and carpentry joints. The subsequent diagnostic report and the detailed design of repairs are outside its scope. [ABSTRACT FROM PUBLISHER]

• Historical carpentry joints can be successfully analysed using numerical methods. • The use of finite element method (FEM) in the analysis of timber elements results in good agreement with experimental tests. • The Hill's yield criterion, despite its limitations, is well suited to simulating non-linear behaviour of wood. • The tested joints achieved approximately 30% of the load-carrying capacity in bending of the reference beams. • The simple analytical model was proposed to assess the load-bearing capacity of tested joints. The article presents numerical analyses of the stop-splayed scarf joints, supported by the results of experimental research. Technical scale beams with historical connections, made of new pine wood (Pinus sylvestris L.) were tested in bending tests. On the basis of the results of the laboratory tests, load–deflection curves, strains in the cross-sections and failure modes were determined. FEM analyses were conducted using the Hill's anisotropic yield criterion. The results of the experimental tests and numerical analyses were compared. Load capacities of the tested joints were estimated also using an analytical method. Supportive analyses were performed to estimate the effect of the changes in the position of the metal connectors on the load capacity of the connections. The problem of determining the load capacity and structural analysis of historical joints of timber elements was discussed. [ABSTRACT FROM AUTHOR]

Inaccuracies within timber step joints are a perennial problem of the wood construction industry. Even perfectly constructed carpentry step joints can become imperfect due to a change in moisture content. The predominant question when looking at step joints with gaps is to what extent the load-bearing behaviour is influenced by these inaccuracies. The authors look beyond this question and investigate if intentionally manufactured gaps could have a positive influence on the load-bearing behaviour and the failure mode of regular and newly designed carpentry joints. [ABSTRACT FROM AUTHOR]

• Improved load-bearing behaviour of newly developed step joints for timber structures. • Relation between onset of failure and ultimate load depends on geometry of carpentry joints. • Experimental determined data on the load-bearing behaviour for timber joints are provided. • Gluing in combination with screw clamps leads directly into a linear elastic load-bearing behaviour. • Failure mode of step joints depends on the geometry. In this paper the load-bearing behaviour of traditional and newly developed timber-timber connections, multi-step and free formed, are analysed within an extensive investigation focusing on joint failure. DIC measurements allowed for an assessment of the initial behaviour of the systems and their specific failure modes. By comparing the stiffness and various load levels to those of typical joint designs the improved load-bearing behaviour of the proposed joints was demonstrated while defining the range of the obtained linear-elastic phase. The results show that the onset of failure, based on the ultimate load, strongly depends on the geometry of the joint. [ABSTRACT FROM AUTHOR]

• Joints, used in historical objects, are now applied in strengthening or repairs. • Changes in joint geometry may influence the levels of load-bearing capacity and stiffness. • The obtained load-bearing in bending was about one-third compared to the continuous beam. • The obtained stiffness was about one-half compared to the continuous beam. The paper presents a description and results of the investigation on the static work of selected splice and scarf joints. Joints, used in historical structures, are now applied mostly in strengthening or repairs of these objects. In the experimental part beams with different joint types were subjected to bending tests. As a result, load–displacement plots, load-bearing capacities and stiffness levels were obtained and compared with the reference continuous beam. In addition, a numerical analysis was performed to compare the stiffness of the beams with different joints. Analysis of the results, conclusions and some further research directions are presented. [ABSTRACT FROM AUTHOR]

Timber frame structures have a long and rich tradition. In addition to their functional and structural value, they are important elements of the cultural landscape. At the turn of the 21st century, concern for nature, resulting from the threat of environmental degradation, contributed to a growing interest in wooden constructions. For these reasons, we have observed the erection of buildings with wooden frame structures in many countries around the world. This trend contributed to the rapid development of wooden structures, new technologies, and innovative architectural solutions. The conducted research mainly focused on the joints used in their construction, as well as their perception. From among many examples, some original and innovative solutions were selected and analyzed. Their creators are famous architects: Renzo Piano, Imre Makovecz, Jürgen Meyer, Kengo Kuma, and Shigeru Ban. The objects presented in this article are distinguished by the originality of their form and by the fact that they are clearly inspired by vernacular architecture. Crucial elements of these objects, such as wooden, steel, and hybrid connections, are analyzed in this article. Because they are intentionally exposed, they play an important aesthetic role in addition to a structural one. [ABSTRACT FROM AUTHOR]

This paper summarises the current state of knowledge related to scarf and splice carpentry joints in flexural elements, also providing some examples of tensile joints. Descriptions and characteristics of these types of joints found in historical buildings are presented. In addition, issues related to forming carpentry joints in historic and heritage structures are discussed. Next, analyses and studies of flexural elements as well as selected examples of tensile joints described in the literature are presented. It is worth noting that authors of vast majority of the publications cited draw attention to the need for further research in this area. They acknowledge that existing descriptions are incomplete and insufficient for bringing about precise understanding and correct description of the static behaviour of these joints. Knowledge about designing and assessing static behaviour of existing carpentry joints is an important issue and is necessary to properly design and strengthen existing joints in historical timber structures. [ABSTRACT FROM AUTHOR]

• Experimental stand for testing of carpentry corner joints is designed and presented. • Experiments on two types of joints, dovetail and saddle-notch are performed. • Numerical models of the joints are defined and the experiments are simulated. • The numerical models are validated on the base of the experiments. • Mechanics of both types of joints is shown and some advice on the modelling is given. This work concerns experimental and numerical research on carpentry joints used in historic wooden buildings in southeastern Poland and western Ukraine. These structures are mainly sacred buildings, and the types of corner log joints characteristic of this region are primarily saddle-notch and dovetail joints; thus, these two types of joints were analysed in this study. The modelling of historic timber structures is a complex issue, so the following steps are necessary to obtain accurate solutions: verification, validation and uncertainty quantification. The first and third steps were performed in a previous study, so the current research aimed to validate the numerical models and perform simulations of carpentry joints. Herein, the authors created finite element models of two types of joints and subsequently analysed the mechanical behaviour of these joints. Due to issues concerning model validation, the authors designed a testing stand for corner joints, which formed a part of a biaxial testing machine. The joints were subjected to horizontal loads (deformations), which may cause damage to the connection. Thus, special parts were designed for the stand, which made it possible to fix the joint and prevented eccentric forces that could possibly damage the machine during testing. The authors presented the differences and similarities in the behaviour of both types of joints, emphasizing the corresponding advantages and disadvantages. In addition, the authors determined which type of joint was the most susceptible to damage and what elements failed first. This paper also showed the complexity of modelling timber structures and the accuracy of the proposed numerical models for both types of joints through comparisons of the numerical and experimental results. This work primary addressed the problems in accurately reflecting material, load and boundary conditions in numerical modelling of tested carpentry corner log joints. [ABSTRACT FROM AUTHOR]

The paper presents the results of an experimental investigation of stop-splayed scarf joints, which was carried out as part of a research programme at the Wroclaw University of Science and Technology. A brief description and the characteristics of scarf and splice joints appearing in historical buildings are provided, with special reference to stop-splayed scarf joints (so-called 'Bolt of lightning') which were widely used, for example, in Italian renaissance architecture. Analyses and studies of scarf and splice joints in bent elements presented in the literature are reviewed, along with selected examples of analyses and research on tensile joints. It is worth noting that the authors in practically all the cited literature draw attention to the need for further research in this area. Next, the results of the authors' own research on beams with stop-splayed scarf joints, strengthened using various methods, e.g., by means of drawbolts (metal screws), steel clamps and steel clamps with wooden pegs, which were subjected to four-point bending tests are presented. Load-deflection plots were obtained for load-bearing to bending of each beam in relation to the load-bearing of a continuous reference beam. A comparative analysis of the results obtained for each beam series is presented, along with conclusions and directions for further research. [ABSTRACT FROM AUTHOR]