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The case-study building of this work is the Medieval Inn of Gralheira (“Pousada Medieval da Gralheira”) located in Vila Pouca de Aguiar, Portugal. This building is an example of the structures of that time, located in Trás-os-Montes, Portugal. A large amount of the built heritage suffers from advanced degradation, making the recovery, increasing the complexity of the rehabilitation and restoration intervention and implying a highly specialized interdisciplinary component. Therefore, the purpose of this paper is to carry out a study of the building in order to perform an analysis of its wood floor and assess its structural behaviour and conservation status. This work also presents some examples of intervention methods and rehabilitation techniques used to solve problems in the masonry structure and wood structures.

In this work, a numerical model of a wood pavement of a medieval building is presented, which was developed and calibrated with values obtained in an experimental campaign of wood specimens extracted from the floor structure and the deformation measured in situ. This model aims to analyse and predict the behaviour of the structure in terms of serviceability limit states. Rehabilitation and reinforcing techniques are described, for specific damages, complemented with a critical comparative analysis to define the most appropriate rehabilitation measures for each situation.

In this work, for the numerical model of the medieval building under consideration, the support of the beams in the walls between 50 per cent embedded and simply supported (hinge supports) was used. Since the beams have some restriction imposed by the wall, they have a delivery about 20 cm in the wall. The consideration of the delivery between beam and columns as simply supported (hinge supports) is a reasonable approximation. There is a difference between the values of deformation obtained in the numerical model and in situ due to the support conditions and also due to the consideration of the pavement loads as a distributed load, which does not correspond entirely to reality, since the pavement confers rigidity to the floor, behaving like a diaphragm. The presented intervention techniques are not applicable in all structures because each building has different characteristics, in terms of materials and construction. The pathologies occur due to many sources and each case is unique, and must be carefully studied before taking decisions about the rehabilitation methods to use.

This work presents a numerical model of wood pavement of a medieval building developed according to some experimental values obtained in an experimental campaign using wood specimens extracted from original beams and based on in situ measurements. This study is part of master thesis of Michael Andrade, an original research work.

NO technical development in all our industrial history has been as highly glamorized as the subject of plastics. It has shown an amazing degree of popular appeal for several reasons, including probably the idea of synthesis from “coal, air and water”, the beauty of colour and finish in decorative effects, and the fact that the objects of early manufacture were those of common use by the general public. Feature writers have regrctably enjoyed a general field‐day revelling in the subject, and unfortunately there has been a tendency towards certain misconceptions and exaggerations in such writings. Plastic aeroplanes now flying, plastic automobiles and plastic homes of the future have been described. Actually there is no such thing today as the plastic aeroplane. The plywood airframe has attained great importance owing to the advent of plastic glues, and what might be termed a “plywood plastic” aircraft is still actually a high‐grade plywood. The plastic automobile bodies envisaged today are secondary structures to be built over a metal framework. The post‐war homes will undoubtedly have dozens of items in which plastics will play a part, but primary load‐carrying structures are not among these components as yet. The plastic industry itself has recently become somewhat concerned about the dangers attendant on over‐glamorization and some remedial action has been studied.

The purpose of this review paper is to provide a review of the most recent advances in the field of manufacturing composite sandwich panels along with their advantages and limitations. The other purpose of this paper is to familiarize the researchers with the available developments in manufacturing sandwich structures.

The most recent research articles in the field of manufacturing various composite sandwich structures were reviewed. The review process started by categorizing the available sandwich manufacturing techniques into nine main categories according to the method of production and the equipment used. The review is followed by outlining some automatic production concepts toward composite sandwich automated manufacturing. A brief summary of the sandwich manufacturing techniques is given at the end of this article, with recommendations for future work.

It has been found that several composite sandwich manufacturing techniques were proposed in the literature. The diversity of the manufacturing techniques arises from the variety of the materials as well as the configurations of the final product. Additive manufacturing techniques represent the most recent trend in composite sandwich manufacturing.

This work is valuable for all researchers in the field of composite sandwich structures to keep up with the most recent advancements in this field. Furthermore, this review paper can be considered as a guideline for researchers who are intended to perform further research on composite sandwich structures.

EXAMINATION of the cross‐section of a tree‐trunk shows the following details of structure: Covering the trunk is the corky bark, the outer layers of which serve to protect the trunk from extreme variations of temperature and humidity, and from mechanical injury; the inner layers, called the bast, serve to conduct the food manufactured by the leaves to actively‐growing parts of the wood and to places of food‐storage in the tree. The bark and the bast together form the rind.

The purpose of this paper is to study the bonding properties of Larch with water‐based polymer isocynate (WPI) adhesive to provide theoretical instruction for practical production of Larch glued laminated timber with WPI adhesive.

This study adopted Japanese JIS K6806 standard to test bonding properties of Larch with WPI adhesive. Scanning electron microscope was used to observe morphography of Larch surface. Micro photos were adopted to show the penetration of WPI adhesive on the radial and tangential surfaces of Larch.

There was significant difference in bonding strength between Larch radial and tangential glue‐blocks glued with WPI adhesive. Dry compressing shear strength of Larch radial glue‐block bonded with WPI adhesive was 1.41 times that of Larch tangential glue‐block bonded with WPI adhesive in normal conditions. Wood failure showed that the difference between Larch radial and tangential glue‐block was caused by wood structure of Larch itself.

The research conclusion that the dry compressing shear strength of Larch radial glue‐block bonded with WPI adhesive was bigger than that of Larch tangential glue‐block bonded in normal conditions. These would be changed if other adhesives were adopted to glue Larch wood.

The conclusion developed in this study provided a practical production instruction for Larch glued laminated timber with WPI adhesive. In order to obtain better bonding properties during the production of Larch glued laminated wood, Larch wood should be sawn into radial boards rather than tangential boards in order to obtain maximum bonding strength of Larch wood.

The paper shows that there was significant difference in bonding strength between Larch radial and tangential glue‐bonded blocks with WPI adhesive. Dry compressing shear strength of Larch radial glue‐block bonded with WPI adhesive was 1.41 times that of Larch tangential glue‐block bonded with WPI adhesive in normal conditions.

Construction works, which contributed to the built environment of the primitive, slave and feudal societies in ancient China, constitute an important component of Chinese history. This paper discusses the nest and cave dwellings as well as the tools used in the primitive society (before 2100 BC) of China. Construction works in the Slave Society (2100‐500 BC) encompassed the construction of city walls as well as wood and earth structures, covering roofs, wall and floor facing, and drainage facilities. The invention of new building materials and construction tools as well as standardization in working procedures and material consumption are discussed in “Feudal society” (221 BC‐AD 1840). The paper suggests that the more than 5,000 years of rich history of construction works in China should not be ignored.

The purpose of this study is the numerical investigation of densification and molding processes of wood. Providing theoretical and numerical approaches with respect to a consistent multi-physical finite element method framework are further goals of this research.

Constitutive phenomenological descriptions of the thermo-mechanical and moisture-dependent material characteristics of wood are introduced. Special focus is given to a consistent hygro-thermo-mechanical modeling at finite deformations to capture the realistic material behavior of wood, especially when it is subjected to densification and molding processes.

Realistic theoretical formulations of different hygro-thermo-mechanical processes are provided. A successful numerical modeling is demonstrated for beech wood by validation at experimental findings.

The constitutive laws and numerical findings are new, as they govern a multi-physical large deformation framework and are applied to the advanced technology of densification and molding of wood.

The antique structures are part of the inheritance that our elders left, being important to preserve their memories. It is important to preserve, rehabilitate and restore the historic buildings protecting the cultural patrimony, attending to the actual comfort and habitability requirements. It is necessary to study the behaviour of the various elements that compose antique structures (masonry and wood) in order to develop assessment measures according to the characteristics of the original materials. The paper aims to discuss these issues.

An experimental campaign to characterize the mechanical behaviour of the wood of the roof of the “sequeiro” of “Quinta Lobeira de Cima”, a building from the twentieth century located in Minho, was carried out. The tested wood specimens are from two different species: chestnut and oak. Compression, tension and static flexion tests according to parallel to the grain direction were performed. Other parameters, such as density, moisture content and longitudinal modulus of elasticity in compression and in tension, were also obtained. The measurement of displacements was made with Digital Image Correlation (DIC).

The results of this study show the similarity between experimental and empirical values for the studied woods species.

This original study aimed at characterizing the mechanical properties using DIC of wood of the roof of the “sequeiro” of “Quinta Lobeira de Cima”, a building from the twentieth century located in Minho (Portugal). This study is part of master thesis of João Martins, an original research work.

The objective of this study is to evaluate the water repellent efficiency of some oil modified solvent‐type alkyd resins, as wood protective formulations (WPs). It was done by surface treating of pine and cedar woods with the five leading brand of alkyd resins that are available in Turkey.

For effective water repellency, various formulations were made by incorporating different concentrations of varnish resin, pigment, solvent, and a substance that repels water. The impact and adhesive strengths of the five different solvent‐type alkyd resins were characterised by using a very simple experimental design.

The swelling variations of unmodified pine and cedar woods were determined in water. Next, the water repellent efficiency of the five different alkyd resin formulations was evaluated. The modification of pine and cedar woods using alkyd resins showed various level enhancement of resistance against water over the unmodified samples. The modification caused a chemical linkage between surface and resin that led to ensuring the intrinsically chemical bonds across the wood/resin matrix interface, which was the main cause to the improved water resistance. However, some WPs were less compatible, hence, had less bonding potential to both woods.

The method developed provided a simple and practical solution to selecting WPs (brands) for pine and cedar woods.

The method for evaluating adhesive strengths of the five different brand solvent‐type alkyd resins to pine and cedar woods were novel and could find numerous applications in surface coating.

This paper aims to show the potential decay resistance of furfurylated wood and investigate possible eco‐toxicity of such materials produced. This paper deals with the environmental aspects and durability of furfurylated wood, both laboratory and field tests are included in the investigations. Results from several decay tests, emission analysis studies and ecotox tests are presented. The results show that furfurylated wood is highly decay resistant. Furthermore, no significant increase in eco‐toxicity of leaching water was found and degradation through combustion does not release any volatile organic compounds or poly‐aromatic hydrocarbons above normal levels for wood combustion. Durability enhancement by furfurylation of wood is not believed to be harmful to the environment. Wood modified with furfuryl alcohol, “furfurylated wood”, is currently being marketed as a non‐toxic alternative to traditional preservative treated wood (wood impregnated with biocides). This paper summarises much of the long term exposure of furfurylated wood ever caried out, and present the first eco‐tox tests on such material ever done.