Timber use in construction Research Papers (original) (raw)

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- Materials Engineering, Wood Science, Timber, Wood chemistry

This paper is based on an evaluation of the industrialization levels and main production systems of Brazilian timber housing producers. Two methods were used to investigate this understudied topic. Literature-based projection was carried out to identify the production system of each sampled company, from the construction technique(s) produced by the same. The second method consisted of face-to-face interviews to identify the current production system of each producer. For both methodologies, the timber housing sector presented a considerable level of industrial development in view of the greater popularity of prefabrication systems. Due to admissions to enable the system identification from the literature-based projections, a result contrast in artisanal production was verified between both methodologies. Despite the sampling difference, the two methods showed typical results for the industrial processes. Thus, few artisanal developers and the visible amount of industrial-based producers could regard this sector as industrial-featured.

- by Victor De Araujo
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- Housing & Residential Design, Construction Technology, Housing, Construction
- by Jan Weber and +2
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- Wood Adhesives, TIMBER STRUCTURES, Timber use in construction, Timber Joints
- by Maristela Gava
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- Engineering, Environmental Science, Carbon Dioxide, Carbon

The essences from sylviculture have been used for pulp and paper and charcoal industry. Hence, value-added examples for construction are essential. However, this use needs to be ensured by criteria prescribed by technical standards such as ABNT NBR 7190 (1997) used here. The present paper evaluated Corymbia citriodora wood to promote the effective construction use through the material characterization. Thus, fourteen mechanical properties and two physical properties were estimated. Changes in the property values under moisture content reduction were observed at two conditions: the initial at 30% and the standard point at 12%, according to prescriptions of this cited technical standard. In total, 2189 repeats were carried out in this document. Seven properties showed visible improvements and influences in the resistance from the observed moisture reduction: perpendicular and parallel compression values and static bending in the modulus of rupture, parallel tensile in the modulus of elasticity, and strength properties of shear stress, tangential cleavage and toughness. Mechanically, Corymbia citriodora wood can be applied efficiently for civil construction, since these results followed the trends pointed out by literature.

- by Victor De Araujo and +1
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- Materials Science, Wood Science, Timber, Mechanical Behavior Of Materials

Eucalypt varieties have been identified as multipurpose materials. With origins in the Oceania region, this genus has been applied for purposes such as pulp and paper, bioenergy, civil construction, and furniture. Very suitable as firewood and charcoal, Eucalyptus microcorys would have good potentialities as structural solutions for construction. But, this wood species is not easily found as building parts in the Brazilian market. This paper aimed to develop a broad evaluation of this species to highlight their features for the utilization as structural lumber. Based on the Brazilian standard document ABNT NBR 7190 (1997), sixteen properties were evaluated at two moisture contents conditions, green and dried points. About 966 repeats were realized in these tests. Nine properties showed influences with the moisture reduction as well as perceptible increases in their resistances: static bending, parallel and perpendicular compressions, and parallel tensile in the modulus of rupture; perpendicular compression and parallel tensile in the modulus of elasticity; and shear stress and hardness properties in parallel and perpendicular directions. Eucalyptus microcorys wood reached good resistance properties, justifying its potentiality for structural uses.

- by Victor De Araujo and +1
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- Timber, Mechanical Behavior Of Materials, Physical and Mechanical Properties of Polymers, Mechanical properties

Nel 1819-23 fu attuato il piano generale di “ampliazione e perfezionamento” del Palazzo dell’Università di Pavia redatto dal prof. Giuseppe Marchesi. Il piano prevedeva anche la realizzazione di un nuovo scalone monumentale, appropriato alla magnificenza dell’edificio ristrutturato. Avendo previsto lo scalone in una parte di edificio già esistente, Marchesi dovette affrontare molti problemi. Volendo coprire lo spazio interno con un’ampia volta a botte con lacunari, ma anche limitare le spese, decise di conservare muri e copertura esistenti. Questi vincoli lo condussero a interessanti scelte progettuali; per quanto riguarda il tetto, per guadagnare altezza per la volta, modificò le capriate esistenti tagliandone le catene lignee e sostituendole con tiranti rialzati in ferro battuto. L’articolo descriverà le vicende storiche dello scalone e le tecniche costruttive adottate per la copertura, nella quale è presente una precoce applicazione di tiranti metallici in capriate lignee.

- by Emanuele Zamperini
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- Engineering, Architecture, Historic Buildings, Neoclassicism

Eucalypt species have become a multiple raw material. Some species have low coverage in the use as durable goods. Low-used variety is the Eucalyptus alba, despite its popularity in railway companies. This study aimed to investigate sixteen physical-mechanical properties of E. alba, aiming to enlarge its use in civil construction. Tests were carried out for different moisture contents (12 and 30%). All results were analyzed by t-test. Apparent density, parallel compression in rupture moduli, parallel compression and tensile in elasticity moduli, cleavage, shear stress, and perpendicular and parallel hardness revealed an increasing with the moisture reduction. Obtained results in properties of shear stress, cleavage and parallel and perpendicular hardness enable E. alba wood utilization in construction for structural flooring production.

- by Victor De Araujo and +1
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- Wood Science, Timber, Mechanical Behavior Of Materials, Eucalypts

- by João Carlos Biazzon
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- Business, Construction Technology, Housing, Construction

Stosowanie drewna konstrukcyjnego i materiałów drewnopochodnych o korzystnej charakterystyce mechanicznej, cieplnej i akustycznej jest podstawową cechą nowoczesnego, lekkiego budownictwa szkieletowego.
Z myślą o śmiałym używaniu drewna w konstrukcjach drewnianych przygotowaliśmy niniejsze opracowanie, w którym krok po kroku (od bazy surowcowej poprzez przerób po materiały finalne) przedstawiliśmy szereg istotnych i przekrojowych zagadnień z zakresu inżynierii materiałów drzewnych, stawiając szczególny nacisk na problematykę produkcji i sortowania tarcicy konstrukcyjnej. Znalazły się tu informacje zarówno z zakresu budowy, wad i właściwości drewna jak i uregulowań normalizacyjnych, a także przegląd technik przetarcia i analiza działania maszyn sortowniczych.

- by Paweł K Kozakiewicz
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- Materials Engineering, Wood Science, Timber, Timber use in construction

Versatile, wood has been used by mankind in furniture, instruments, utensils and construction. About timber buildings, this critical review discusses their valuable and sustainable features that label their multiple options. Numerous contributions were compiled from the author's collection and prospection in relevant databases. Construction techniques were featured, vocations were identified and production systems were remarked to detail wood-based resources and residues. Discussions and suggestions were raised as promoting strategies. Secular buildings prove the convenience of wood materials in construction, since they have decent levels in sustainability, durability, stability, value added, aesthetics, strength and weight. Timber construction enables artisanal to industrial productions and traditional to contemporary techniques with different materials, sizes and architectural styles. Global barriers are marked by obscurities about logging and illegal deforestation, and deficiencies in the regulations of native species. The utilization of sustainably sourced wood, sylviculture as a viable social-economic driving force and several advantages of timber construction are positive reasons. Actions were proposed to drive policy and multiply timber buildings, since they form a promising segment for emerging bioeconomies of innovative nations. Changes in wood consumption to enhance sylviculture combined with the waste reutilization should intensify the sustainability of timber construction and establish industrial synergies.

- by Victor De Araujo
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- Construction Technology, Construction Management, Wood Science, Timber

Both round and handle produced (sawn or rough-hewn), timber constitutes one of the oldest building raw materials. Wood can be engineered to produce structural beams and boards. Today, wooden housing is the most valuable and viable alternative to replace masonry. In turn, it is a modern model, whereas it presents good attributes of raw materials rationalization, water-free processing, work site cleaning, and rapid production. The strong industrialization of timber housing with prefabrication of parts should be the centre of attention in the future, consonantly with housing shortage in many countries, particularly in developing and underdeveloped ones. This paper aims to present a state of the art about timber housing topic and its aspects.

- by Victor De Araujo and +3
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- Architecture, Housing in Developing Areas, Construction Technology, Housing And Sustainability

As part of phase two of Fall Field School students PI, and CO-PI split into two groups to record historic split-log dugout vessels located at the Charleston Museum and Middleton Plantation.This preliminary report
will touch upon historical evidence, construction details, and formation processes to explore
some of the more significant themes that concern the nature of these historic vessels that Accommodation represents.(Originally published in The Nautical Research Journal, Vol. 56, No. 1, Spring 2011)

- by Lynn Harris and +2
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- Maritime Archaeology, Southern Studies (U.S. South), Timber use in construction, Small Traditional Wooden Boats

Osmanlı konaklarında kullanılan ahşap iskelet sisteminin Hacılar, Çatalhöyük ve Boğazkale arkeolojik araştırmalarında gördüğümüz üzere çok uzun bir zamana yayılı teknolojik evrimi söz konusudur. Günümüze ulaşan Osmanlı konaklarının hemen tamamı 19. yüzyılda yapılmıştır. Anadolu'da 18. yüzyıldan kalan yalnızca 10 kadar ahşap konak bulunmaktadır, bunların da hemen tamamı yanlış restorasyonlarla kaybedilmiş bulunmaktadır. Osmanlı konakları üzerine yapılan araştırmalar elde kalmış çok kısıtlı sayıda örnek üzerinden yapılabilmektedir. Öte yandan, restorasyon etkinlikleri tüm hızıyla sürüyor olmakla birlikte, Osmanlı konakları ile ilgili araştırmalar 21. yüzyılda akademik gündemden düşmüş bulunmaktadır. Bildiride, arkeolojik araştırmaların bulguları ışığında ahşap iskelet sistemin nasıl geliştiği anlatılacak, Osmanlı kadı içtihatlarına dayanarak ahşap elemanların nasıl standartlaştırıldığı ve 18. yüzyılın sonlarında yürürlüğü giren Ebniye Nizamnamesi ile de yapı boyutlarının nasıl şekillendiğini tartışacağım. Küçük Kıyamet olarak isimlendirilen 10 Eylül 1509 depremi ile yine en büyük depremlerden biri olarak kaydedilen 10 Temmuz 1894 depremleri arasında Osmanlı yapı stokunun depreme dayanıklı hale getirilmesi çok önemli bir deneyimdir. Bu tartışmayı Osmanlının sosyo-ekonomik çevresinden bağımsız götürmek yanlış olur. Sonuçta Anadolu'dan Balkanlar'a uzanan bir kuşak üzerinde ortaya çıkan Osmanlı konaklarının arkitektoniğinin tanımladığım etkiler (impacts) altında nasıl oluştuğu konusunda savlarımı ortaya koyacağım. Bu araştırma Osmanlı sivil mimarisinin, geleneksel Mimarlık Tarihi izleği dışında bir okumadır.

There is some agreement and much debate among interested parties about what constitutes 'sustainable housing'. The term 'sustainable' is used somewhat liberally to mean different things to different listeners. Governments, institutions, interest groups and individual designers often address certain aspects while ignoring the bigger picture. But the bigger picture is such a multivalent issue that includes aspects outside the architect's immediate remit such as location, transport, security, procurement policy and post-occupancy analysis and management. Or are these outside the architect's remit? Teaching sustainable housing within conventional architecture programmes means educators are restricted to identifying certain key issues that students should learn within a specific teaching timeframe, given the necessity for the students to demonstrate ability in the mainstay of architectural education – individual design approach, urban design, apartment planning, r...

- by Jim Roche
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- Engineering, Housing, Timber, TIMBER STRUCTURES

Timber load bearing floor structures of Italian historical constructions are complex systems made of girders, joists, subfloor, and completing components (lath to cover planking joints, small boards to cover the link between joists and girders, etc.). These floors are placed in and connected with the load bearing walls, thus constituting a more complex structural system.
The need of strengthening of timber load bearing floors could issue from: timber decay (due to insects, fungi, fire, or creep), increase in loads, changes in safety and serviceability standards.
Actual cases show countless states with regard to: building techniques; material state of preservation; size of the gap between required and provided performances; aesthetical, historical and material interest of ceiling and flooring.
In the light of contemporary architectural preservation theories, several values must be considered while choosing from among the conceivable systems for the strengthening of timber floors: aesthetical quality; signs of usage; technological features; material characteristics. Other needs must also be evaluated along with those values: the requirement to assure physical and aesthetical fruition of the building; the need to respect the original technological conception of the structure; the compatibility of the strengthening solutions with the existing structure, the possibility to remove it, and maintain it in efficiency; moreover the added elements should be clearly recognisable as contemporary.
This paper aims to single out the primary values to be considered, and to assess the most common strengthening solutions with regard to these aspects and to the actual state of the floor structure.

- by Emanuele Zamperini
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- Conservation, Cultural Heritage Conservation, Heritage Conservation, Timber

Excavations of the Egyptian New Kingdom fortress in Jaffa (Tel Yafo, ancient Yapu), on the southern side of Tel Aviv, were renewed by the Jaffa Cultural Heritage Project from 2011 to 2014. This work is an outgrowth of the project’s reappraisal of Jacob Kaplan’s excavations in the Ramesses Gate area from 1955 to 1962. As the Egyptian fortress in Jaffa is the only one excavated in Canaan, its archaeological record provides a unique perspective on resistance to Egyptian rule from ca. 1460 to 1125 B.C.E., but especially during the second half of the 12th century B.C.E., when Jaffa was twice destroyed. Radiocarbon dates from these two destructions are presented, and it is suggested that they offer the clearest basis thus far for proposing ca. 1125 B.C.E. as a terminus post quem for the end of Egyptian rule in Canaan. The archaeological evidence, taken together with textual sources, yields a picture of local resistance to the Egyptian military presence in Jaffa likely originating in Canaanite centers located throughout the coastal plain.

- by Aaron A Burke and +10
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- Egyptian Archaeology, Ramesses II, New Kingdom (Archaeology), Egyptian ceramics

From 2011 to 2014, the Jaffa Cultural Heritage Project excavated several phases of an Egyptian New Kingdom gate complex located in Jaffa, Israel. Excavations in 2013 revealed extensive remains of the Level IVB/Phase RG-4a gate, which was destroyed in a major conflagration ca. 1135 B.C.E. In 2015, work began on a digital reconstruction of the gate's architecture and its environs. This reconstruction sheds new light on the gate complex and the interrelationships between its many architectural elements. The process has led to some suggestions as to how the extant remains might be reconstructed, but also illustrates how much has been lost and that such reconstructions are inherently dependent on excavated remains from other, sometimes quite distant, sites.

- by Aaron A Burke and +1
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- 3D Reconstruction, Ramesses II, 3D Modelling (Architecture), Egypt and Canaan

""La tesi si inserisce nell'ambito di ricerca della storia delle tecniche costruttive e analizza l'evoluzione tecnologica e tipologica delle coperture lignee in Italia nel periodo che va dall'inizio del XIX alla metà del XX secolo.
Dopo una parte di inquadramento delle condizioni tecnologiche, del contesto socio-economico e produttivo generale e delle teorie e pratiche costruttive delle coperture lignee italiane della fine del XVIII secolo, la ricerca ne analizza i progressivi mutamenti cercando di individuare alcune "fasi omogenee" e di rintracciare i nessi tra i processi evolutivi del contesto e quelli che interessano le coperture lignee.
Particolare attenzione è attribuita allo sviluppo delle tipologie costruttive delle capriate e alla diffusione di altri tipi di strutture lignee di copertura (cavalletti centinati, archi, portali a due o tre cerniere, ecc.), rapportati ai vari aspetti del contesto tecnico-culturale e produttivo: livello e tipo di formazione culturale e tecnica dell'ingegnere e dell'architetto; sviluppo e diffusione delle teorie della meccanica delle strutture e della resistenza dei materiali; cambiamenti nei modi di produzione e lavorazione dei materiali edilizi; variazione dei prezzi della manodopera e dei materiali; invenzione di nuovi sistemi di connessione dei legnami.""

During the period of Ottoman rule in Hungary (1541-1686), palisaded castles of differing sizes were typical elements in the border-castle networks on both sides of the battlefront: the Ottoman and the Christian. Archaeological remains (post-holes, beam structures, parts of palisades) complement the data in the written sources, making perceptible and measurable the great quantities of timber used in the building of castles. In the case of the Ottoman palisaded castle at Barcs and in that of the royal palisaded castle at Bajcsavár (southern Transdanubia), attempts were madeon the basis of archaeological observations and reconstructions of ground plansto determine the number of palisade stakes used for the walls at the time of building, as well as to establish the number of trees felled in order to make them. By way of environmental history researches, an answer was sought to the question of how much the construction of these palisaded castles impacted on the forests in their respective districts. In the case of Barcs Castle, investigations were conducted into whether forest clearance in its vicinity can be reconstructed on the basis of pollen samples. Other issues examined are how far forest clearance extended from the two fortifications, its intensity, and the approximate quantities of timber yielded by it.

- by Gyöngyi Kovács
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- Archaeology, Environmental History, Ottoman Hungary, TIMBER STRUCTURES

Many of New Zealand’s large number of older, timber-framed and -clad buildings are poorly insulated and need a thermal upgrade, both for occupant wellbeing and to reduce greenhouse gas emissions. However, retrofitting insulation into walls is known to increase the likelihood of interstitial moisture damage. This research therefore investigates the risk that retrofitting the walls of the country’s older buildings with glass-fibre insulation, as is currently the norm, will result in interstitial moisture damage, and whether the use of wood-fibre insulation can reduce that risk. These questions are investigated through a literature review, the testing of scale walls using a climate chamber, and computer modelling. The three key findings are that: 1) there is a risk of moisture damage, but weatherboard walls perform better than computer modelling might suggest,
2) wood-fibre insulation does prevent condensation forming, but is not a satisfactory solution to the problem as the resulting high moisture content puts it at risk of decay, 3) a critical factor is the vapour permeability of the wall underlay. The main conclusion is therefore that either insulation is acceptable providing the inherently high vapour permeability of the weatherboard wall is maintained, but that this is not achievable using many of the underlays currently certified for use in New Zealand.

- by Nick Braxton
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- Timber, New Zealand, Timber use in construction, Thermal Insulation

Conference proceedings - 10th International Conference on Structural Analysis of Historical Constructions SAHC16 , K. Van Balen&E.Verstrynge (Eds), 13-15 Settembre, 2016 – Leuven, Belgium; Published by: CRC Press Taylor & francis Group,... more

- by sandra tonna and +1
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- Seismic Hazard, Traditional Architecture, Nepali Architecture, Timber use in construction

Wooden housing is one of the most sustainable building alternatives. In many European and North American countries, wooden houses provide the most common, economical, and practical solution for construction. The timber buildings present adequate levels of durability, acoustics, and thermal comforts. Despite their popularity, wood houses do not have a standardized classification to define and organize their main aspects. In literature dealing with timber construction, most authors emphasize structural systems for large spans (bridges, hangars, roofs, etc.). The presence of some classifications of timber construction results in unclear issues, and few studies have covered and regarded wooden buildings as residential construction typologies. Accordingly, this paper proposes a classification that connects the aspects and details of wooden housing materials in relation to the industrialization level and chronological origin. We expect this classification to assist in a better understanding of distinct wooden housing techniques commercially produced worldwide, diffusing their concepts and possibilities as forestry-timber products.

- by Victor De Araujo and +3
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- Civil Engineering, Construction Technology, Housing And Sustainability, Housing

- by Maristela Gava
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- Business, Housing, Timber, Wooden Architecture

Negli ultimi decenni si è avuto il passaggio dall'intervento a danno avvenuto ad attività manutentive programmate e preventive. Essendosi riconosciuta l'importanza di tutelare anche gli elementi costruttivi più degradabili, nell'ambito dei beni storici, la manutenzione programmata è stata ribattezzata conservazione programmata: alla sostituzione degli elementi degradati sono stati contrapposti la riparazione e la conservazione. Tali interventi non possono prescindere dalla conoscenza degli elementi tecnici e della loro composizione nel sistema tecnologico. Per la redazione di un piano di conservazione programmata, sono quindi necessarie indagini conoscitive atte a fornire i dati per la stima del rischio di deterioramento e a fissare periodicità e tipo di controlli e attività manutentive. L'articolo illustra lo studio storico e tecnologico dei sistemi di copertura del Palazzo centrale dell'Università di Pavia. Il palazzo ha subito nel tempo interventi radicali di ristrutturazione e ampliamento, per giungere all'attuale configurazione dopo l'annessione (metà 20° secolo) della ex sede dell'Ospedale San Matteo. La stratificazione delle fasi costruttive rende particolarmente complesse morfologia e struttura delle coperture, delle quali non esisteva documentazione sistematica. Lo studio condotto ha consentito di rilevare speditivamente, ma in maniera affidabile: geometria delle falde e delle strutture portanti, materiali posti a sostegno del manto, punti e percorsi di accesso alle varie parti del sottotetto. Le informazioni raccolte e sistematizzate costituiscono la documentazione fondamentale per la valutazione dei rischi connessi alla infiltrazione di acqua dalle coperture e per la definizione delle strategie di intervento e manutenzione, oggetto della successiva fase della ricerca.

- by Richard Etlin
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- Engineering, Civil Engineering, Architecture, Architectural History

Due to its great availability in planted forests in Brazil, Eucalyptus saligna appears as a good species to be exploited, in order to assist in the consumption of wood for construction purposes. The aim of this research was to determine the physical and mechanical properties of Eucalyptus saligna wood species for its use in civil construction. The evaluation was based on 16 physical and mechanical properties obtained according to NBR 7190 (1997) standard. Two values of moisture content were considered: 30% (above the fiber saturation point) and 12% (equilibrium moisture content) according to NBR 7190 (1997). All obtained results obtained were statistically analyzed according to the t-test at the 5% level of significance. In addition, the characteristic strength properties were also determined, for batch classification in the strength classes recommended by the Brazilian standard. Eucalyptus saligna had an apparent density of 0.58 g/cm³ and a basic density of 0.73 g/cm³. The mechanical properties, presented fc0 and fc0,k equal to 46.80 and 32 MPa, respectively. The results indicated that Eucalyptus saligna wood can be used in the construction of timber structures as structural member

- by Victor De Araujo and +2
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- Mechanical Engineering, Wood Science, Timber, Wood Engineering

The time and the place in which trusses were invented is uncertain; however, it is certain that they were already in use during Roman Empire. The oldest extant material evidences date back to the 6th century AD and witness the simultaneous presence in Italy of two constructive types that coexisted for centuries. The two types of truss are distinguished from each other based on the different relationship between posts and tie-beams: in closed-joint trusses, posts are connected to tie-beams with carpentry joints (e.g. tenon-mortise); in open-joint trusses, the posts are physically detached from the tie-beam but possibly linked to it with a metallic strap.
The paper will outline the idea that, under the effects of vertical static loads, there is no significant difference in structural behaviour between the closed- and the open-joint trusses. Indeed, under ordinary loads, in Italian-style trusses the deflection of the tie-beam is greater than the lowering of the bottom of the post, and carpenters were aware of this since the post/tie-beam joint is always traction resistant; therefore, the tie-beam is usually hanging from the post. Subsequently, the joined analysis of many clues (structural behaviour, evolution of carpentry joints, evolution and spread of iron reinforcements) will be used to support the thesis that the progressive prevalence of the second type over the first (which essentially disappeared since the mid-18th century) is due to the progressive understanding of the behaviour of damaged trusses and to the gradual diffusion of metallic elements for joints reinforcement.
When in a closed joint truss a material decay affects the rafter/tie-beam joint, the tie beam starts to be charged by a concentrated load, which generates a flexional action even though no sensible displacement is visible; decay progression can eventually lead to tie-beam breakage, especially if it is weakened by a mortise.
When the same decay affects an open-joint truss, as soon as the decay starts, if there is no iron reinforcement, the bottom of the post suddenly hits the tie-beam, and there is the risk that it could collapse. On the contrary, if the rafter/tie-beam joint has iron reinforcing elements, it acquires a certain ductility and, in case of decay, the bottom of the rafter slowly and progressively slips, causing a lowering of the post towards the tie-beam, which denounces the beginning of a decay and warns against the risk of collapse.
Hence, progressive affirmation of open-joint trusses can be seen as the achievement of a higher safety in event of material decay of the rafter/tie-beam joint.

- by Emanuele Zamperini
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- Timber, Wooden Architecture, Wood Engineering, Trusses

Bioeconomy, circular economy, land use reduction, sustainable use of natural resources, reduction of CO2 emissions in the atmosphere and recycling are the keywords which the building world must face in the near future, as the environmental emergency can no longer be postponed. In order to disseminate in the scientific community the different possibilities of timber as a sustainable building material throughout its whole life cycle and to provide the professionals with suitable decision-making tools for a conscious design, within the cultural and scientific scenario of the recent years, the paper serves as a moment of reflection highlighting how a closer integration between different sectors (forestry, building, energy, industrial and waste management) can find, in the use of timber, an opportunity to significantly reduce the overall impact of a built environment life cycle.

- by Cesare Sposito and +1
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- Engineering, Forestry, Environmental Sustainability, High-rise building (Architecture)

On the very south-eastern edge of Slovakia, in the former Uzhorod county and near the current border with Ukraine and Hungary, two rare monuments of rural residential construction have been preserved. They are connected by the same floorplan of six-room double-wide structure and the same, framework walls – in one case with wattle, in the other one slotted filling. Different is the shape and construction of the roof. Their common feature is also unoccupancy followed by deterioration and deficiency of official monument protection. Probably these are the last two structures of the construction-disposition type in Slovakia.

This paper aimed to analyse timber houses produced in Brazil, identifying the main market locations. In this unprecedented insight, an interview survey was carried out by a semi-structured questionnaire applied on respective producers. First question was developed to estimate quantitatively the annual Brazilian production of timber houses for a triennium. The second question delimited the market extension regarding the main destinations of produced houses. Face-to-face interviews were used to collect data with house producers. Margin of error was calculated to validate sampling process and respective results. A wide respondent amount about 51% of this sector, and the consideration of six different local states were main strategies to confer validity and reliability of the sampling process. From 12,000 to 20,000 timber houses were annually produced in Brazil during this triennium, showing an increase from 0.32 to 0.52% per year. Brazilian timber housing market prioritizes three extensions: local, state and regional (neighbouring states). Compared to European countries, Brazilian production volumes have been representative, although masonry residences still prevail in the domestic market. Leading domestic markets are located in higher concentration zones of producers in the Southern and Southeastern states, for example, Santa Catarina, Rio Grande do Sul, Paraná, São Paulo, and Minas Gerais. Many producers have commercialized nationwide, reflecting in the greater visibility for timber houses. Despite lower export levels, African and European continents symbolize the main destinations for timber houses produced in Brazil. Both internally and externally, market potential of timber housing is further promising for this respective production sector in Brazil.

- by Victor De Araujo
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- Housing, Timber, Wooden Architecture, Housing markets

Despite the promising future to industry in Brazil, most production sectors still suffer with the access to newer industrial technologies. Some very specific and limited incentives have been offered by the local Government to stimulate these companies. However, the forestry-timber sector hardly has access them, due to the several barriers and bureaucracies. Together with other factors, it is a visible reason to the lack of the renovation of their production lines, as well as the improvement of their industrial technologies. Industrial parks with modern technology contribute directly to products which better quality, and it could be a favourable way to the Brazilian development in industrial aspect. For that reason, it is important to perform studies to stimulate this sector. This study aims to verify the situation of the timber machinery of the wooden housing manufacturers in the Brazilian State of São Paulo. It was realized through a survey applied directly to the companies' owners. This work revealed that the largest share of these companies of São Paulo State presented update equipment to produce wooden houses. Nevertheless, these companies still could improve the technology of their manufactures with robotic and automated machinery, looking for a better productivity.

- by Victor De Araujo
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- Wood Science, Timber, Industrial Engineering, Prefabricated wood

Building temporary structures requires a change in the approach with respect to “ordinary” design. Some aspects (e.g. speed of construction, ease of disassembly) assume greater importance, others (e.g. durability) take second place. Temporary shelters for archaeological excavations also set further issues: the need to minimize construction time, in order to extend to the maximum the time available for excavation activities; the need to build in a complex plani-altimentric context and often in the absence of a definitive survey of the site; the impossibility of using usual construction machinery and to build “ordinary” foundation structures. Working in the Middle East requires you to interact with local workers who do not speak western languages and have a quite different technical culture; moreover, since excavations are often located in peripheral areas, the variety of materials available at affordable price and for prompt delivery is almost always limited. Together with general and methodological considerations, the paper illustrate the project of temporary shelters for the archaeological excavation at Kınık Höyük (South Cappadocia, Turkey). In relation to local technical and economic context, depending on the nature of the site, it was decided to build timber frame structures made of standardized locally-produced sawn beams, assembled by nailing. A fundamental requirement of the project was to ensure resistance to high winds that blow on the site from all directions: therefore the structure was braced using struts and X bracings, and suitable stabilizing masses have been set up to overcome the lightness of the structure.

- by Emanuele Zamperini and +2
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- Archaeology, Architecture, Conservation, Heritage Conservation
- by Maristela Gava
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- Business, Housing Policy, Construction, Wood Science

Die natürliche Nähe des Menschen zum Holz ist zwiespältig, vor allem seitdem der Mensch mächtig genug ist, es technisch zu beherrschen. Die lange Zeit der vielseitigen Nutzung bezeugt bei steigender Vertrautheit und Sicherheit im Umgang eine hochflexible Verwendung des so einförmig und beschränkt aufgefundenen Materials bei zugleich stetiger Verankerung der Naturnähe durch den immerwährenden sichtbaren Holzbezug; die Ambivalenz zwischen Herrschaft und Demut gegenüber dem ewigen Urstoff lässt sich bis heute nachzeichnen, ja sie erreicht in der modernen Gestaltbarkeit von industriellen Produkten eine neue Dimension. In ihr bilden sich stoffliche Umformungen als permanente Konstruktionsanpassung, mechanische Modellvorstellungen als zunehmende Idealisierung sowie architektonische Ausgestaltung zur Integration in einen formalen Kontext gemeinschaftlich ab. Das Holz hat sich als moderner Baustoff zunehmend ebenbürtig neben den Industriebaustoffen Stahl und Stahlbeton positioniert. In ihm zeigt sich heute stärker als je zuvor das Abbilden und Umbilden eines alten Naturstoffs, im zunehmend technischen Sinne, zu einem immer leistungsfähigeren Werkstoff.

- by Mario Rinke
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- History of Construction, Timber use in construction

A Basilica dedicated to Saint Michael was first built in the Longobardic period (6th-8th cen-turies), however the present building dates back to 11th-12th centuries. The church was built in Romanesque style and it is unanimously considered one of the masterpieces of the Lombard architecture of the period. During the subsequent centuries, the building underwent several changes and restoration works. Dealing with the roof of the central nave, the rebuilding of the vaults (1488-91) was the most relevant work. Traces of the pre-existent vaults are still visible in the attic; they were much higher than the present ones and thus they were in-compatible with the structural organisation of the existing timber roof structure. Therefore the conception of this structural system probably dates back to that period. In 1860–75 the building underwent works of stylistic restoration and since the 1930s many preservation in-terventions were done in order to consolidate the decayed sandstone of the façades; however, these interventions did not affect the roof structures. In 1942 two reinforced concrete wall plates were built on the top of the longitudinal walls of the central nave and the timber trusses now lay on them. Since the early 19th century the church has been studied by many art and architecture historians, and many surveys and drawings have been done, both before and af-ter the stylistic restoration works. However the historians’ attention has focused mainly on the formal features of the building and on the construction phases of masonry structure. In many of the drawings the roof structures are not even represented; in the others, they are only sketched out schematically. Therefore, the knowledge of the timber roof structures of the church is still very poor. In this situation, the study of archival documents and the survey and in situ investigation of the timber trusses play a fundamental role in the historical knowledge of this important but neglected timber structural complex. The structural complex is com-posed of a sequence of seven quite different trusses supporting the upper layers of timber elements (i.e. purlins, joists and laths) and the roof tiles. The paper advances a hypothesis about the dating of each of the trusses, based on the matching of the archival data with the critical interpretation of the surveyed signs: structural type of the truss, type of joints, signs of woodworking tools (e.g. axes, saws, hand drills, chisels), assembly marks, signs of reutiliza-tion of timber elements, type of iron reinforcement elements, etc.

- by Emanuele Zamperini
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- Engineering, Civil Engineering, Architecture, Architectural History
- by Juliana Cortez B
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- Engineering, Housing in Developing Areas, Housing And Sustainability, Housing

The strength of a building relies heavily upon the transfer of load from one connection to another [1,2]. A solid and reliable connection method must be utilized to increase the strength of timber panel and enable the structure to withhold an excessive amount of stress [3-5]. In wood buildings, an effective connection will provide the building with strength and ductility [6]. However, there are many connections needed in a wooden structure therefore an economical and durable connection is required to assemble a prefabricated panel quickly and inexpensively in mass production [6].

Computational processes are fast becoming central to the production of work across numerous industries in ways that are shifting workplace practices, as well as the relevance, identity, and value proposition of established professions. In the architecture, engineering and construction (AEC) industry globally, the uptake of digital and computing technologies is ushering in significant changes to long-standing ways of designing, delivering, and constructing the built environment. While architecture has long been computerized, having enrolled computing for administrative tasks and computer-aided design (CAD) software for documentation and representation since the 1980s, it is now negotiating a significant intersection with computer science logic and methods. It is a timely moment then to revisit the work of Japanese architect Shoei Yoh who, from the late 1980s onwards, forged a less-instrumentalist and more collaborative relationship with emerging computing technology. The re-examination of this not-too-distant architectural past is argued here as an important way to advance a critical reconceptualization of architecture’s relationship to technology.

Wood products shrinks as they dry and swell as they absorb moisture, either liquid or vapour from the atmosphere. Unless these changes in dimension are kept to the minimum, they may result in unsatisfactory service of wood products and structures. This study aimed to appraise the moisture content of selected timber species available in the market with a view of relating the moisture content with the provisions of the NCP 2:1973. The research study relates to moisture content of twenty selected wood species; Afara (Terminalia superba), Mohogany (Khaya senegalensis), Marike (Anogeisus leiocarpus), Iroko (Chlorophora excels), Doka (Isoberlinia doka), Erun (Erythrophleum ivorense), Bomax (Bomax costatum), Shear butter (Vetellaria parodoxum), Black plum (Vitex doniana), African rosewood (Pterocarpus erinaceus), being hardwood and African Tulip-Tree (Spathodea campanulata), Alstonia (Alstonia boonei), Cotton tree (Ceiba pentandra), Obeche (Triplochiton scleroxylon), Sauce berry (Cordia Africana), Dorowa (Parkia biglobosa), Daniella (Daniella oliveri), Malina (Gmelina arbrea roxb), Ashoka (Saraca indica) and Mansonia (Mansonia altisima) all being softwood were examined. The moisture content test was carried out in accordance and procedures specified in BS EN 13183-1: 2002 "Moisture content of a piece of sawn timber-Determination by oven dry method". Findings from the Descriptive statistics showed that Mahogany (Khaya senegalensis) had the least moisture content of 4.28% while Alstonia (Alstonia boonei) recorded the highest moisture content of 21.13%. It was observed that there were no two woods with equal moisture contents. In addition, the selected wood species met the requirements for moisture content of building timber for various purposes as stated in N.C.P 2:1973. This appraisal reveals that there should be standard codes for moisture contents (M.C) on the different types of timber in timber markets of Northern Nigeria.

- by Osianemo Omole
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- Forestry, Structural Engineering, Timber, Wood science and technology