Timber-framed shear walls play a crucial role in providing stiffness and resistance to timber buildings subjected to horizontal forces induced by wind or earthquakes. Enhancing the load-carrying ...capacity of a timber-framed shear wall subjected to horizontal forces, is achieved most effectively by reinforcing the connection between sheathing and framing members. Since however, the shear resistance of such a wall is determined by the resistance of the individual wall elements, strengthening the sheathing-to-framing connection is possible only to an extent where the shear resistance is not limited by the resistance of the sheathing panel.
This study presents experimental investigations of the shear resistance of OSB/3 panels, when used as sheathing material in timber-framed shear walls, which revealed that the shear resistance of the OSB/3 sheathing was reduced in comparison to the shear strength of the OSB/3 panels themselves. The reduction is attributed to additional stresses in the panel, and is accounted for in design rules specified in the German National Annex of Eurocode 5 (DIN EN 1995-1-1/NA:2013-08) and in the CEN Enquiry (ENQ) draft of Eurocode 5 (prEN 1995-1-1:2023-09). The results of the investigations confirm the reduction factor which is proposed in prEN 1995-1-1:2023-09, for wall elements with one-sided sheathings. However, the reduction factor specified for the design of wall elements with two-sided sheathings could not be confirmed. The results of this study performed with comparably massive and rigid timber framing revealed no difference in the reduction factor for timber-framed shear walls with one- or two-sided sheathings.
•Tensile and shear tests on OSB/3 panels of thicknesses 12 mm, 15 mm, 18 mm and 25 mm.•Investigation of the load-carrying capacity of OSB/3 sheathed timber-framed walls.•Evaluation of the limit of OSB/3 panels in the application as sheathing material.•Comparison of results from experiments with design rules given in Eurocode 5.
This investigation analyses the influence of the depth and the distance between studs on the fire resistance of lightweight timber-framed (LTF) walls lined with gypsum plasterboards. The simplified ...model used to determine the fire resistance in Eurocode EN 1995-1-2 provides very conservative values, as few parameters are considered. The new generation of Eurocode EN 1995-1-2 includes an upgrade of the simplified model, allowing us to predict the fire resistance of LTF wall assemblies more accurately. This separating function method considers the number, the thickness and the material of the protection layers, but does not explicitly consider the variation of the depth and the distance between the studs for the calculation of the insulation time of the assembly, besides including some limitations for both parameters. To demonstrate the influence of these parameters, 36 numerical simulations were carried out using the finite element method previously validated with experimental tests. The results obtained from the parametric analyses confirmed that such parameters affect the fire resistance of the LTF wall assemblies in a significant way. In addition, the results revealed an important contribution in the study of LTF wall assemblies against fire resistance, demonstrating the need for including extra geometric parameters in the simplified model in order to increase the accuracy of current models.
•Mathematical modelling of timber-framed walls.•A braced frame with one fictive diagonal is used.•Model is suitable for analysis of lateral loads on the timber frame structure.•Simplicity of the ...model, easy to use and suitability to use it with simpler and cheaper programs.
In the current paper a simple mathematical model with a fictive diagonal for a quick and accurate determination of the racking stiffness of composite timber-framed wall elements is developed. The stiffness of the timber-framed wall is determined through the analytical calculation of the wall element, taking into account the bending and the shear flexibility of the composite wall element, the flexibility of the fasteners between the timber frame and the sheathing board along with the flexibility of the tensile and compressive support at the foundations. The model furthermore allows for consideration of the walls with door and window openings in addition to that of tensile cracks appearing in the fibre–plaster sheathing boards, with the stiffness of the wall element being reduced. By varying the fictive diagonal cross-section of the numerical model according to the presented facts, the appropriate stiffness of the timber-framed wall can be obtained and used in the 3D static model. The model is suitable for any three-dimensional modelling with the analysis of the lateral load impact (wind, earthquake) on the building being carried out by using simple 3-dimensional FEM software, which is extremely useful for engineering application.
•Different design approaches are used to dimension the timber-frame panel buildings.•The stiffness of the anchors affects the horizontal stiffness of the building.•TGWE and walls with openings affect ...the distribution of horizontal forces in walls.
Behaviour of the timber-frame panel buildings under the horizontal forces is largely dependent on the type of the chosen design approach. The distribution of the horizontal forces along the timber-framed wall elements is thus influenced by the stiffness of the diaphragm, the stiffness of the wall elements and their connection with one another. However, there is a dilemma whether all the contributions that have an effect on the stiffness of the timber-framed walls are taken into account or not. The factors that influence the stiffness of the wall are the hold-down anchoring, the influence of the walls with openings and the timber-glass wall elements and the influence of the vertical loads. This paper numerically analyses the behaviour of the three-storey timber-frame panel building under the horizontal forces, using different design approaches. The basic approaches are upgraded by including different contributions to the stiffness of the timber-framed walls. Using different design approaches, a comparison of the horizontal force distribution among the walls, vibration periods and horizontal deformations of the building is being made. The results show that the design approach used has a great influence on the distribution of horizontal forces along the walls and the horizontal deformation of the building itself. Taking into account full-height timber-framed walls only, the horizontal deformations of the building could be underestimated.
•An iterative method to trace the racking load–displacement curve of timber framed walls.•The method is based on the assumption of rigid-body behaviour for the timber members and sheathings.•Only two ...DoFs are needed to model the kinematics of the timber frame.•The numerical model is validated against laboratory test results.
A new method to assess the raking performance of Platform timber framed walls, is provided in this study: each component of the unit wall assembly is assumed as rigid, hence allowing to drastically reduce the overall number of DoFs involved within the model. The timber frame in particular, is modelled as a mechanism, having only two DoFs (regardless of the number of studs) corresponding to the horizontal and rotational displacements of the header beam. For a given imposed horizontal displacement Δh, the corresponding racking load P(Δh) is computed by numerical relaxation, allowing to consider a continuous function to represent the load-slip curves of the connections. A comparison of the numerical analysis against laboratory test results is provided, showing the method’s capability in predicting the raking strength of the wall, despite the assumed reduced number of DoFs.
The study analyses the possibilities of improving timber-framed wall thermal insulation in historical buildings. Due to the specific nature of these building objects, whose historical value during ...the course of thermal modernisation measures cannot be affected, methods of increasing thermal insulation which require little intervention in the structure of partitions and which can be accepted by the appropriate authorities of monument protection were only indicated. The analysis was conducted using an example of a historical building from the area of Lower Silesia, for which several possible solutions of wall thermal insulation with the use of modern materials that are highly-effective in terms of thermal insulation, were proposed, and the results of carried out thermal calculations were then summarized and interpreted.
This paper presents mathematical modelling of timber-framed wall where a braced frame with one fictive diagonal is used. The model is suitable for analysis of lateral loads on the structure. Its ...advantage compared to other models is its simplicity, the fact that it is easy to use in practise, and its suitability for use with simpler and cheaper programs for static and dynamic analysis. Further numerical calculations were performed, which showed good approximation with experimental studies and with the finite element method. The Tower 6 program for static and dynamic analysis has been used to model timber-framed walls. Appropriate stiffness of timber-framed wall is obtained by varying the cross-section of the fictive diagonal. Because the cross-section of the fictive diagonal is directly connected to the analytical calculation of the stiffness of the timber-framed wall, this model is also able to factor in different spacing distance, different sheathing boards, the appearance of tensile cracks in a sheathing board, as well as walls with glazing or openings.
En Madrid perviven numerosas casas con estructura de entramado de madera, con catalogación Estructural o Integral. Sin embargo, este sistema constructivo de muros de carga interiores entramados y ...muros de fachada de ‘doble hoja’ es poco conocido. El descubrimiento y análisis de proyectos antiguos de posadas, con información gráfica y escrita no publicados hasta la fecha (1669-1798), y la reconstrucción de sus detalles constructivos, explican esta tipología, desde los primeros esqueletos de madera rellenos de albañilería, hasta el inicio de las estructuras metálicas. La Posada del peine, la más antigua conservada, y con el plano más antiguo con muros entramados dibujados, desvela el origen y desarrollo de estas estructuras; también la modificación del edificio original (1616 -1863) y su posterior ampliación (1891-2). La metodología desarrollada demuestra su validez para estudiar construcciones históricas similares, y llena el vacío bibliográfico existente, resolviendo también los errores en las referencias encontradas.
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