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Traditional architecture is the result of collective experience in the optimum use of available materials in a given location and adapted to specific conditions and needs. Although forms and groups also depend on other cultural and social issues, the constructive techniques used depend mostly on geographical conditioning factors such as altitude, hydrography, lithology, climate, etc. This text aims to analyse the possible relationships among the multiple variants and specific geographical conditioning factors of each location; in turn, this should provide an understanding of the reasons motivating or reducing their use and the mechanisms adapting these techniques to these conditioning factors. The analysis cross-referenced GIS systems from a database compiling information on 1160 half-timbered walls with a series of themed maps containing information on geographical factors. The conclusions reached show that a single technique adapts to different geographical conditioning factors, giving rise to a wide range of solutions which can provide greater durability and improved habitability. This capacity to adapt to the location is a lesson in sustainability that can be applied at present and is above all part of the intrinsic wealth and value of traditional architecture. [ABSTRACT FROM AUTHOR]

Treatments of organic objects to extract ferrous compounds from waterlogged archaeological wood are well documented. For several years, numerous laboratories have been seeking to determine suitable conservation treatments for such organic objects. For chemical treatments, complexing agents such as EDTA and DTPA, along with acids such as citric and oxalic acids, were selected. In addition, oxidants and reducing agents were tested as pre-treatments to improve extraction rates. In fact, chemicals produce a selective reaction on ferrous compounds, which may improve or be inhibited by complexation or dissolution reactions. Their action depends on the type of compound to be extracted and those present inside the wood. The objective of this study was to make a comparative assessment of the various chemical conservation treatments identified and complement the evaluation of their extraction efficiency with a study of their impact on organic matter by adding criteria such as their visual aspect (using a spectrocolorimeter) and physicochemical actions by means of infrared spectroscopy and micromorphological observations. The effectiveness of EDTA was confirmed, as was that of citric acid, despite some questions arising concerning the presence of wood fibers in the treatment solution, even after rinsing. On the other hand, the extraction rate of oxalic acid, which has a very acidic pH, was unsurprisingly lower, but its visual and anatomical results raised the possibility of using it over a short period of time in view of the effectiveness observed on the wood surface. Pre-treatments improved extraction rates, except in the case of EDTA, which independently had a high extraction rate. It was observed that pre-treatments did not appear to cause any significant chemical degradation of the organic matter. This study provides a tool to assist conservators in selecting a chemical treatment that is in line with the state of decay of the wood, the characteristics of the ferrous compounds to be extracted, and the conservation objectives. [ABSTRACT FROM AUTHOR]

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

Present results provided new information on the practice of removing iron from waterlogged wood using chelating agents. Two series of samples were selected: small waterlogged wood samples of Quercus spp., Pinus sylvestris L. and Pinus pinaster Aiton, and a portion from the dismantled shipwreck Huguangjiao I. Iron extractions were carried out using disodium ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA). Samples were characterized by environmental scanning electron microscopy coupled with dispersive energy spectrometry, micro-Raman spectroscopy, atomic absorption spectroscopy, Fourier transform infrared spectroscopy and dynamic mechanical analysis (DMA), the latter used to evaluate viscoelastic properties. The extraction efficiency of both products was good, although it depended on the wood state of preservation, being higher in more decayed material. Still, the extraction procedures induced a limited effect on the decayed wood tissue, affecting both cell wall chemical composition and physical characteristics. Moreover, a significant difference existed between the two agents. In decayed hardwoods, they had an impact on both E' (decrease) and tanδ (increase), mostly apparent for DTPA. The difference between DTPA and EDTA was also more evident when the frequency was varied in DMA tests. In contrast, the well-preserved softwood was not affected by the considered treatments. [ABSTRACT FROM AUTHOR]

Wood has a wide range of applications in the artistic field, most of the time used as a support for works of art, for example, in panel paintings. Compared with stones and metals, wood is by far the material most utilised for sculptures. Through the identification of wood species, a study of timbers used in statuary in Europe, with a deeper exploration of the works of art preserved in Italy, can provide further insights for historical–artistic studies. Indeed, in reality, generic wood does not exist, but there are different timbers. This is a notion that the wood fine carving artists/craftsmen knew well. The initial idea of this study was to verify whether timber features could influence the formal results in figurative carving; therefore, a specific database that had been developed to catalogue the carving works was used for which the identification of wood species was carried out through reliable methodologies. The aim of this research was to analyse the relationship between the timber species used in statuary, the formal results of carving, and the thickness of the preparatory layer, through the data stored in a specific database, called ArISStArt. It contains a sort of registry of artistic carving and inlay works: For each artefact, a record was compiled consisting of different fields, which contains the historical–artistic information available, including the images of the artefact and also types of timber/s used for its creation, with a link to the relative field. The number of the recorded artefacts is, at present, 480. On most of the artefacts, more than one sample was taken; therefore, the total number of identifications carried out corresponds to 691. Based on the results, the vast majority of wooden statuary is carved from hardwoods, more specifically hardwoods, with diffuse porosity and small variations in density within the growth ring. The timber most present is poplar, followed by lime and walnut. With the listed three timbers, almost 80% of the artefacts recorded in ArISStArt were created. [ABSTRACT FROM AUTHOR]

St Francis of Assisi Church is an historic religious building in the centre of Valletta, Malta's capital. Through analysis of the roof structure we have determined the timber species used in its construction, their state of conservation and the date of different building phases and maintenance work. The study provides an historical and cultural framework for the entire building. Apart from identifying the type of timber and typically English way of construction, dendrochronological dating has revealed two precise phases of intensive restoration, dating to 1681 and 1876, respectively. For both periods, the timber's provenance points to the Eastern Alps, based on dendrochronological master chronologies of European larch (Larix decidua). Furthermore, a single Norway spruce (Picea abies) board from the vault was dated to 1684. This church is a typical example of Maltese culture, intermingled with other cultures that have resulted in a very particular architectural-work. [ABSTRACT FROM AUTHOR]

This work is aimed at showing the results of a work of identification of the wood species used for the construction of the mechanical components of a historic pipe organ. The instrument was built in 1895 in Pistoia (Tuscany, Italy) for a church of a small municipality in the north-west of Tuscany, the summer residence of a family of ancient European nobility; it is therefore a large monumental organ, still original. During the restoration operations, and consequently on the disassembly, it was possible to carry out a complete sampling of the wooden components that are normally not directly accessible. The sampling was performed under the supervision of the restorer, through the cut and drawing of very small samples and with minimally invasive criteria. The identification was performed by observing thin sections, manually cut, by means of an optical microscope. The results of the identification carried out on the 25 samples are reported. The identified timbers are not very numerous and the most represented one is poplar (Populus sp.). [ABSTRACT FROM AUTHOR]

The viscoelastic properties of wood samples treated with various consolidants [polyethylene glycols (PEGs), lactitol and trehalose, Kauramin, polydimethylsiloxane (PDMS) and trimethoxymethylsilane (MTMS), rosin and polyethylene-L-tartaramide] were evaluated by means of dynamic mechanical analysis (DMA) in order to clarify their effects with regard to the conservation of wood objects. Two softwoods, medium-decayed silver fir (Abies alba) and highly decayed maritime pine (Pinus pinaster), and two differently decayed oak hardwoods (Quercus spp.) were used. In addition, the selected parameters [retention, volume variations and equilibrium moisture content (EMC)] were evaluated to assess the consolidation efficacy. The results showed that in treated wood, both the storage modulus and tanδ depend upon the level of degradation. The impact of the consolidating product was greater in more degraded wood (a higher product amount inside the artefact) compared to well-preserved material, where also wood played a role (also when the products were applied at high concentrations). The values of the different viscoelastic parameters also depend upon the ability of the products to interact with the wood matrix; this characteristic is fundamental to the nature of each consolidant. Lactitol-treated samples showed the highest stiffness increases, whereas those treated with selected PEG combinations and rosin displayed noticeable tanδ increases (high dissipative behaviour). [ABSTRACT FROM AUTHOR]

The relationship between the mechanical properties of Cunninghamia lanceolata (Chinese fir) wood and the development of fungal decay was investigated with the aim of implementing a statistical model useful as a non-destructive and a fast method for determining the state of conservation of in-service timber structures. Artificial decay due to brown rot fungi was induced on wood specimens and physical and mechanical test were performed periodically, as well as anatomical observation of wood, FT-IR spectroscopic and XRD diffraction analysis. As a result, Chinese fir was confirmed to have a good durability against fungi, showing a mass loss percentage of 7.21% on average after 14 weeks of exposure. On the contrary, the mechanical properties reduced dramatically during the decay test: a 19% decrease was observed for compression strength and 21% for tensile strength. The mechanism of decay was explored and the corresponding damage constitutive model was proposed. [ABSTRACT FROM AUTHOR]

The weathering of wood through abiotic factors has been extensively studied. Much less research has been conducted on the influence of biotic factors on wood in exterior use that is not in ground contact, i.e. use class 3. There is especially a lack of research concerning the influence of the presence of bacterial and fungal communities on the weathering process of wood. The project aim is to identify any synergistic effects between biotic factors such as bacteria (Actinomycetes and Eubacteria) and fungi (Basidiomycota and Ascomycota) and abiotic factors such as light, temperature and moisture on the weathering of wood surfaces in use class 3. This paper presents results such as the amount of colony forming units (CFU), environmental scanning electron microscope analysis, colour changes and moisture content (MC) from preliminary experiments where wood surfaces were either naturally or artificially weathered. In order to study the interactions of fungi and bacteria on wood during the weathering process, the presence of microorganisms on natural weathered oak and Douglas fir surfaces had to be validated first. With the help of a surface contact test, microorganisms on the wood surfaces were transferred to agar plates and consequently incubated so that they could grow in appropriate conditions. Once the microbiological colonies had developed sufficiently, they were separated by selecting sections from the colonies and replated on fresh agar. A microcosm scale experiment, meaning the transfer of one specific bacteria and one fungi together in one petri dish, was carried out. This trial revealed that certain bacteria have an influence on the growth rate of certain fungi. In addition, an artificial weathering test was carried out in a QUV, which allows the degradation of samples using specific and known abiotic degrading parameters. The observation of the artificial weathered wood samples revealed that microorganisms are most definitely present in the QUV test apparatus and may influence the test results. [ABSTRACT FROM AUTHOR]

The triangular truss is the most typical structural frame of Italian historic roofs. Mostly, but not exclusively, used to transfer vertical loads to walls, it has been developed during centuries into different geometrical compositions by using also different wood species and materials. The aim of this article is to describe the most typical features of the Italitan trusses and the survey procedures by using practical examples taken from hundreds of inspected structures. The complete assessment of a roof structure is an interdisciplinary activity, while this article is intended to present the point of view of the wood technologist, only partially considering the structural aspects. The survey is performed on the basis of a step-by-step procedure, with increasing levels of analysis: starting from a general analysis of the structure as a whole to the analysis of the single members and connections, gaining so far more and more detailed information, which can explain the results of the previous level of analysis. The most common pathologies occurring on timber trusses and structures are also described. Finally, before general conclusions, a quick case study, based on a roof structure from the beginning of 19th century, is shown, presenting the principal results obtained. [ABSTRACT FROM AUTHOR]

This paper deals with the identification of the wood species used for the production of wooden tools in an ancient plant for manual paper production. After a quick historic contextualisation of the importance of the paper industry developed in the Pescia district (Tuscany, Italy), this paper describes the process of manual paper production and the different tools, mostly wooden, used by the workers. The historic plant "Le Carte" still preserves these tools, which were sampled to scientifically identify the timber species. Samples were drawn from any wooden component of the equipment involved in the whole manual paper making process. Sampling was performed on any portion of the artefact where the species of origin was not clearly and reliably identifiable by eye, or aided by a manual magnifying lens. In total, 1223 identifications were performed and 25 timber types observed. Most of timber identifications regard the large mould collection (434 artefacts, 1154 identifications, 17 timbers), while the equipment included fewer artefacts, identifications and timbers. Obtained results are then technologically discussed, considering the features of each species and the specific needs of each final use. [ABSTRACT FROM AUTHOR]

Work on thermal pools at Poggetti Vecchi in Grosseto, Italy, exposed an up to 3-meter-thick succession of seven sedimentary units. Unit 2 in the lower portion of the succession contained vertebrate bones, mostly of the straight-tusked elephant, Palaeoloxodon antiquus, commingled with stone, bone, and wooden tools. Thermal carbonates overlying Unit 2 are radiometrically dated to the latter part of the middle Pleistocene. This time span indicates that early Neanderthals produced the human artifacts from Poggetti Vecchi. The elephant bones belong to seven individuals of different ages. Sedimentary facies analysis and paleoecological evidence suggest a narrow lacustrine-palustrine embayment affected by water-level fluctuations and, at times, by hydrothermal water. Cyclic lake-level variations were predominantly forced by the rapid climatic fluctuations that occurred at Marine Isotope Stage (MIS) 6–7 transition and throughout the MIS 6. Possibly an abrupt, intense, and protracted cold episode during the onset of MIS 6 led to the sudden death of the elephants, which formed an unexpected food resource for the humans of the area. The Poggetti Vecchi site adds new information on the behavioral plasticity and food procurement strategies that early Neanderthals were able to develop in Italy during the middle to the late Pleistocene transition. [ABSTRACT FROM PUBLISHER]

Examining the timber structure supporting the roof of Giotto's bell tower in Florence, this paper discusses the combination of non-destructive (NDT), wave-based methods for the characterization of timber structural elements. In particular, it analyses the on-site applicability of selected wave-based techniques for the identification of decay, damage, defects, and moist areas in structural timber. The applied NDT techniques are IR termography, microwave reflectometry, time-of-flight tomography, and mapping by means of elastic waves. Experimental results are compared with data obtained by means of consolidated NDT techniques, such as the electric resistance method for moisture content estimation and the drill-resistance test for decay characterization. These can be considered non-destructive, although they are invasive. The wave-based NDT methods are found to be a value-added complement to routine methodologies for a holistic diagnosis of timber members. Normal practice based on visual inspection, decay detection through point measurements of drill resistance, and moisture content estimation through local readings of electric resistance, can be substantially improved through full-field, multi-sensor, multi-resolution imaging. Nevertheless, while the diverse NDT methods illustrated here can be useful for screening large areas in a completely non-invasive way, local measurements (i.e., the drill resistance and the electric resistance measurements) are still necessary. [ABSTRACT FROM AUTHOR]

Timber structures can be degraded during their life both by structural problems and by biological degradation factors like fungi and insects. The occurrence of those biodegradation agents could lead to a loss of their structural integrity, in the absence of appropriate maintenance. An early assessment of the decay is even more important when the wooden structures are part of historical buildings, in the interest of conservation of cultural heritage. This article presents an application of microwave reflectometry for the in situ evaluation of timber structures. The measurement system allows detecting anomalies inside the material in a non-destructive and non-invasive manner. The reflection coefficient is measured by means of a vector network analyzer (VNA) using a double-ridge antenna which transmits the continuous-wave (CW) microwave signal and receives the signal reflected by the material under investigation. Measurements on laboratory models demonstrated the feasibility of the method. Results obtained on timber beam sections, compared with the findings of traditional investigation methodologies, demonstrate the potentiality of microwave reflectometry, suggesting its possible usefulness during the diagnostic phase as a non-invasive tool for preliminary screening. [ABSTRACT FROM AUTHOR]

Timber structures can be degraded during their life both by structural problems and by biological degradation factors like fungi, and insects. The occurrence of those biodegradation agents could lead to a loss of their structural integrity, in the absence of appropriate maintenance. An early assessment of the decay is even more important when the wooden structures are part of historical buildings, in the interest of conservation of cultural heritage. This work presents an application of microwave reflectometry for the in situ evaluation of timber structures. The measurement system allows detecting anomalies inside the material in a non-destructive and non-invasive manner. The reflection coefficient is measured by means of a vector network analyzer (VNA) using a double-ridge antenna, which transmits the continuous-wave microwave signal and receives the signal reflected by the material under investigation. Measurements on laboratory models demonstrated the feasibility of the method. Results obtained on timber beam sections, compared with the findings of traditional investigation methodologies, demonstrate the potentiality of microwave reflectometry, suggesting its possible usefulness during the diagnostic phase as a non-invasive tool for preliminary screening. [ABSTRACT FROM PUBLISHER]