Timber Framework Research Articles

Assessment of timber element mechanical properties using experimental modal analysis

Nowadays, timber frameworks become one of the most widespread types of material in building constructions. Their configurations and joints are usually complex and require a high level of craftsmanship to assemble. To properly assess the behaviour of timber elements, many assessment techniques are available but they present some limitations. This paper presents a non-destructive approach to finite element updating using results from experimental modal data. Several timber beams in a free supported condition were analysed in order to extract the frequency response functions and their bending natural characteristics (frequency, damping and mode shape). A finite element model was derived, taking into account the possible effect of local defects. With the intent to estimate the corresponding mechanical properties, a procedure of modal updating was carried out by implementing various modal criteria. The objective function was selected from the conventional comparison tools (absolute or relative frequency difference, and/or modal assurance criterion). This assessment tool was tested to determine the mechanical properties of timber beams (elastic moduli and damping properties). To verify the modulus, a series of static 4-point bending tests and STS04 classifications were conducted. In addition, sensitivity analysis reduced the number of parameters to be updated (Young’s modulus along the beam length and the corresponding shear moduli), showing that the present method is an efficient alternative to conventional wood tests.

A Historical Timber Frame Model for Diagnosis and Documentation before Building Restoration

The aim of the project that is described in this paper was to define a four-level timber frame survey mode of a historical building: the so-called “Andlau's Seigniory”, Alsace, France. This historical building was built in the late XVIth century and was in a stage of renovation in order to become a heritage interpretation centre. The used measurement methods combine Total Station measurements, Photogrammetry and 3D Terrestrial Laser scanner. Different modelling workflows were tested and compared according to the data acquisition method, but also according to the characteristics of the reconstructed model in terms of accuracy and level of detail. 3D geometric modelling of the entire structure was performed including modelling the degree of detail adapted to the needs. The described 3D timber framework exists now in different versions, from a theoretical and geometrical one up to a very detailed one, in which measurements and evaluation of deformation by time are potentially allowed. The virtually generated models involving archaeologists, architects, historians and specialists in historical crafts, are intended to be used during the four stages of the project: (i) knowledge of the current state of needs for diagnosis and understanding of former construction techniques; (ii) preparation and evaluation of restoration steps; (iii) knowledge and documentation concerning the archaeological object; (iv) transmission and dissemination of knowledge through the implementation of museum animations. Among the generated models one can also find a documentation of the site in the form of virtual tours created from panoramic photographs before and during the restoration works. Finally, the timber framework model was structured and integrated into a 3D GIS, where the association of descriptive and complementary digital documents was possible. Both offer tools leading to the diagnosis, the understanding of the structure, knowledge dissemination, documentation and the creation of educational activities. The integration of these measurements in a historical information system will lead to the creation of an interactive model and the creation of a digital visual display unit for consultation. It will be offered to any public to understand interactively the art of constructing a Renaissance structure, with detailed photos, descriptive texts and graphics. The 3D digital model of the framework will be used directly in the interpretation path, within the space dedicated to “Seigniory” of Andlau. An interactive touch-screen will be installed. It will incorporate several levels of playgrounds (playful, evocative and teaching). In a virtual way, it will deal with the different stages of building a wooden framework and clarify the art of construction.

Thermal Performance Evaluation of a Dynamic Insulation Technology Applied to a Timber Framework House in a Real Environment

This paper presents the thermal performance evaluation of a dynamic insulation technology applied to the building envelope of a timber framework house. The concept of dynamic insulation technologies is to draw outside air in through insulation materials in a wall to recover conduction heat loss from inside the building. The authors applied dynamic insulation technology to the walls and ceiling of a timber framework house to allow outside air to pass through permeable insulation materials within the walls and ceiling. The experiment was conducted at a building in Sapporo, Hokkaido to evaluate the thermal performance of a building envelope with dynamic insulation technology in a real environment. The results showed that the dynamic insulation technology can significantly reduce heat loss through the building envelope.

構成要素の連携による寄棟屋根母屋・端部小屋束生成

The purpose of this study is building the part of hipped roof purlin and end strut generation of the frame element generation system by cooperation of constituents in timber framework construction house. The part of hipped roof purlin and end strut generation is built as a multi agent system that the purlin and end strut modeled in the straight line cooperates with close purlins and end struts, repeats correction and decide the right position based on the positioning rules by analyzing the positioning situation of purlin and end strut in hipped roofs and the information of the circumstances. In this study, the knowledge that is obtained on the building this part is reported.

최욱의 한옥 리노베이션에 나타난 전통과 현대 사이의 연속성 논의

The purpose of this paper is to investigate into a way that the traditional Hanok can achieve a continuity between the past and the present, by researching on the architect Choi Wook's Hanok renovation projects: Samchungdong Hanok (2000), Dugaheon (2004) and Hakgoje (2007). Choi is well known for his liberal change of the Hanok by inserting modern architectural vocabularies into its traditional timber framework. This research analyzed the projects focusing on the themes, such as, 'the change of the ground/ platform', 'the deconstruction of the traditional room concept' and 'the plain wall and horizontally-long window of modernism', and as a result it argues that his design illustrates a creative inheritance of the traditional with a certain degree of continuity between the past and the present. For that reason, it could be said that Choi's Hanok renovation suggested us for one possibility of Hanok's new way to evolve in the future.

A HISTORICAL TIMBER FRAME MODEL FOR DIAGNOSIS AND DOCUMENTATION BEFORE BUILDING RESTORATION

Abstract. The aim of the project that is described in this paper was to define a four-level timber frame survey mode of a historical building: the so-called "Andlau's Seigniory", Alsace, France. This historical building (domain) was built in the late XVIth century and is now in a stage of renovation in order to become a heritage interpretation centre. The used measurement methods combine Total Station measurements, Photogrammetry and 3D Terrestrial Laser scanner. Different modelling workflows were tested and compared according to the data acquisition method, but also according to the characteristics of the reconstructed model in terms of accuracy and level of detail. 3D geometric modelling of the entire structure was performed including modelling the degree of detail adapted to the needs. The described 3D timber framework exists now in different versions, from a theoretical and geometrical one up to a very detailed one, in which measurements and evaluation of deformation by time are potentially allowed. The virtually generated models involving archaeologists, architects, historians and specialists in historical crafts, are intended to be used during the four stages of the project: (i) knowledge of the current state of needs for diagnosis and understanding of former construction techniques; (ii) preparation and evaluation of restoration steps; (iii) knowledge and documentation concerning the archaeological object; (iv) transmission and dissemination of knowledge through the implementation of museum animations. Among the generated models we can also find a documentation of the site in the form of virtual tours created from panoramic photographs before and during the restoration works. Finally, the timber framework model was structured and integrated into a 3D GIS, where the association of descriptive and complementary digital documents was possible. Both offer tools leading to the diagnosis, the understanding of the structure, knowledge dissemination, documentation and the creation of educational activities. The integration of these measurements in a historical information system will lead to the creation of an interactive model and the creation of a digital visual display unit for consultation. It will be offered to any public to understand interactively the art of constructing a Renaissance structure, with detailed photos, descriptive texts and graphics. The 3D digital model of the framework will be used directly in the interpretation path, within the space dedicated to "Seigniory" of Andlau. An interactive touch-screen will be installed. It will incorporate several levels of playgrounds (playful, evocative and teaching). In a virtual way, it will deal with the different stages of building a wooden framework and clarify the art of construction.

All Saints’ Church, Brixworth, Northamptonshire: The Development of the Fabric c. 1100 to 1865

Following the publication of a detailed monograph on the Anglo-Saxon phases of the church, this is an account of its development from the late 11th century until the eve of the Victorian restoration in 1865–66. The Romanesque contribution to the fabric is mainly represented by the late 12th-century south doorway, but a series of reset corbels implies a complete re-roofing; the pitch of the roof was reduced in the late middle ages. Major changes in the late 13th and 14th centuries included the growth by stages of the south-east chapel, the replacement of the Anglo-Saxon apse by a square-ended chancel, and the addition of a bell stage and spire to the west tower. New data from surveys by the Brixworth Archaeological Research Committee have made it possible to propose a detailed sequencing for the south-east chapel, while alternative interpretations of a timber framework in the bell stage of the west tower, not previously recorded, can be suggested.

The Clutha’s First Dam: The Nil Desperandum Project at Quartz Reef Point, 1864–66

The first dam on Central Otago’s Clutha River was not the 1956 Roxburgh dam, but a gold-mining enterprise’s structure built ninety-three years earlier. If it had succeeded, it would be lauded with other colonial-era New Zealand engineering feats such as the Denniston Incline and Raurimu Spiral; because it failed, it is forgotten.In 1864, two years after the goldfield began, miners organized Cromwell businessmen as shareholders to form the Nil Desperandum Company. Where the Clutha was bifurcated by Knobby Island at Quartz Reef Point they would build a timber crib cofferdam at each end of the island and pump the enclosed space dry to mine the riverbed. The upstream structure was to be built at 45° to the flow, 270 metres long, 15 metres thick and 7·5 metres high, constructed from timber frameworks filled with stone and backed by an additional rockfill buttress.This paper discusses this engineering feat, including how it was built, what it achieved and when the methodology was used elsewhere in New Zealand.

スリップ型復元力特性を有する建物の地震最大応答加速度に関する研究

We experimented on the shaking table of the 1/6 scale models of slip hysterisis characteristic that assumes the timber framework construction. And, we experimented the addition of the damper to those models. We summarized the influence of the modulus of eccentricity, the floor stiffness, and the oil damper upon seismic peak response displacement from this shaking table in reference literature (1). This report verified the influence that the modulus of eccentricity, the floor stiffness, and the oil damper exert on the seismic peak response acceleration and the change in the dominant frequency.

Life Cycle Assessment of Timber Components in Taiwan Traditional Temples

For years, research on the life cycle of conventional building materials (e.g. reinforced concrete and metal structures) has been studied; however very little literature can be found in non-conventional materials such as timber. Ever since the 1999 Chi-Chi earthquake that happened in Taiwan, many traditional timber framework buildings were destroyed or severely damaged. For the past decade, enormous amount of resources have been invested by the Taiwanese government to begin various studies on traditional timber building techniques, timber material testing etc. Although correct building technique or proper use of building material are crucial towards establishing a structurally-sound timber framework, without proper building maintenance, the structural integrity will also be jeopardised in future. With the continual decline of timber supply, re-using existing timber materials becomes especially important in building conservation. In this paper, eight Taiwanese traditional temples are used to study the life cycle of historic timber framework. Based on past records of each building's restoration process, statistical calculations of various timber components at different repair stages and oral interviews with the traditional master carpenters, architects and timber surveying units, results shown that alteration design during repair stage is recommended as it enables architects to give more informed repair advice. However if improper or unsuitable measures are carried out during emergency rescue work, timber deterioration will only aggravate further instead of being salvaged. Lastly, a theoretical calculation method for timber framework life span is proposed by using 50% as the critical point for overall structural failure.

A STUDY ON SEISMIC PEAK RESPONSES IN A SDOF ELASTO-PLASTIC SYSTEM OF SLIP HYSTERESIS CHARACTERISTICS

The timber frame work construction has the majority of the house in Japan. These buildings have the very large slipping properties in the hysteresis characteristics. In this paper, the seismic peak response forecast was verified about a single-degree-of-freedom (SDOF) elasto-plastic system of slip hysteresis characteristics. The seismic peak response forecast was done by the elasto-plastic response analysis, the property of energy conservation, and the equivalent linearization. And the accuracy of each forecast method was verified. Result, the property of energy conservation doesn't consist when the slip ratio of slip hysteresis characteristics is large, and the equivalent linearization can forecast the seismic peak responses for slip hysteresis characteristics.

ARCHITECTURE AND BASIC MOTION OF A FRAME ELEMENT GENERATION SYSTEM BY COOPERATION OF CONSTITUENTS

The purpose of this study is building the architecture and the basic motion of a frame element generation system which generates the whole frame element appropriately in timber framework construction house by constituents of a house repeat an adjustment to the mismatching between the local frame elements based on an idea that the consistency between all the frame elements in the house which has been ended design completely is maintained. Specifically, agents that are constituents that extracted from timber framework construction house and implemented functions perceiving surrounding environment, exchanging information with the touched agent, recording those information and generating constituents from the information and the generation rule are put in the site space which is virtual space. The system is a multi agent system that all the frame elements of a house are determined by the agents cooperate and repeat generations and adjustments.

La construcción de una bóveda de crucería en la Escuela Técnica Superior de Arquitectura de Madrid

The Department of Construction in the Escuela Superior de Arquitectura de Madrid carried out a pedagogical experience of great interest. In the framework of a new discipline (Workshop on Gothic Art of Construction), the students built a ribbed vault. Gothic vaults are studied from several points of view, but the knowledge acquired in all these fields is never confronted with real practice. The aim of this pedagogical experience was to invert the terms, that is to rediscover and instil meaning into the theory through the physical experience of the construction. Along the process, the students were made conscious of the following aspects inherent to this type of construction: first of all, we planed to acquire historical knowledge of the object and its author; second, we took up its geometric study and the discovery of its spherical shape, and, third, we carried out the design of its life-size geometric lay out. In the next stage, we proceeded to carve the different parts of the vault, to pass on to build the centering which, once finished, enabled us to tackle the assembly of the vault. Finally, we removed the timber framework of the vault. This article deals with this whole process. The students who carried out the experiment of building a real vault can attest how to upgrade theoretical knowledge through actual experience is the best way to learn.

Acoustic Comfort in Timber Frame Dwellings

Timber framework has become the most common construction technique in the world for private dwellings. In Belgium, although masonry construction still constitutes the most important market share, the number of new houses with timber framework increases each year. Unfortunately the acoustic insulation of this construction type compares unfavourably with traditional masonry construction. In order to learn more about acoustic performance of timber framework houses and to compare them to the performance of traditional masonry houses, a measurement survey has been carried out, on fifteen single family dwellings with timber framework or heavyweight wood. This paper presents the results of the in situ measurements. The measurements were of façade sound insulation, sound insulation of the inner walls (horizontally and vertically) and impact noise insulation. Similar measurements also have been carried out on houses made of traditional masonry in order to compare the results. A comparison of the results collected in the laboratory and Belgian comfort criteria are also presented. Finally, results of acoustic tests in a multi-family timber construction are presented. The weaknesses of construction techniques observed during the study are discussed.

THE EFFECT OF SUBSTRATE DEPTH AND SUPPLEMENTARY WATERING ON THE GROWTH OF NINE HERBACEOUS PERENNIALS IN A SEMI-EXTENSIVE GREEN ROOF

THE EFFECT OF SUBSTRATE DEPTH AND SUPPLEMENTARY WATERING ON THE GROWTH OF NINE HERBACEOUS PERENNIALS IN A SEMI-EXTENSIVE GREEN ROOF

Étude archéologique des élévations de la maison n°15 de la rue Croix-Baragnon à Toulouse

An archaeological study of the elevations of the house n° 15 rue Croix-Baragnon, at Toulouse. The house in the rue Croix-Baragnon is one of the rare medieval residences to have survived. Hitherto, only remains of the façade were known to us, but recent restoration work has provided the opportunity to observe the interior masonry and the different layers of plaster that it was covered by. This archaeological analysis of the elevations has enabled us to identify different series of repairs and their extent, and eventually to propose reconstitution hypotheses for this medieval residence. We can thus reconstitute an edifice with two main bodies, the side of the house alongside the road, and a back courtyard. The lower walls were built of brick, whereas timber framework was used for the upper parts. Built in the 14th century, the house was much altered during the 16th and 17th centuries : the timber-framed constructions were demolished, the back part of the building was extended at the expense of the courtyard, the circulation system was reorganized and the heart of the medieval house, hitherto oriented towards the road, was moved to the back. Comfort in the house was also regularly improved ; the ground floor, which remained the trade area, shows evidence of numerous rearrangements.

The Excavation of Batsford Mill, Warbleton, East Sussex, 1978

THE CHANCE DISCOVERY of a waterlogged wooden beam during the cutting of a drainage ditch led to the excavation of the timber framework of a medieval water-mill. Almost half the water-wheel survived in situ. A little 14th-century pottery was found in the wheel-pit; its structure was extremely similar to that of the approximately contemporary period I mill at Chingley.1 The mill at Batsford was probably used for grinding grain; no trace of the mill building itself was found.

Celtic vitrified forts: Implications of a chemical-petrological study of glasses and source rocks

The term “vitrified forts” refers to remnants of stony fortifications of early Iron Age in which constituent rock fragments and boulders have been melted and/or welded together by heat, apparently in situ. The methods used are a matter of controversy, and even the question whether the firing was constructive or destructive is disputed. In this study we present bulk analyses of some twenty source rocks and of fifty glasses (in petrographic thin sections) from eleven sites and attempt to relate these data to the processes (and purposes) producing the observed sintering, welding and melting. The results are consistent with progressive partial, sometimes total, melting of the rocks used. In agreement with most previous investigators we conclude that no exotic rocks (although limited amounts of clays or organic debris cannot be excluded) were used as flux nor were easily fusible materials selected. On the other hand, simply burning an ordinary (of the later murus gallicus type) timber-laced wall cannot account for the evidence of strongly reducing conditions and sustained high temperatures, probably for days and in some cases well above 1000 °C. Rather, the fires seem to have been contained, perhaps by filling the space between the rocks in the timber framework with soil, clay and combustible materials, e.g. peat, brushwood and domestic debris. We cannot conclude whether the firing was accidental, or set by enemies or by the builders. In any case, the builders appear to have used more sophisticated techniques than previously believed to ensure the durability of their constructions.

Bar Coliseo, en Sevilla

This bar is situated inside the «Coliseo» building, which houses a cinema, as well as a number of commercial establishments. In order not to break the unity of the total project, no attempt has been made to alter the exterior aspect of the bar. No attempt was made, either, to make it into an intimate, club type of bar, now so much in fashion. Rather has it been given a diaphanous style, seeking the best possible use of the floor space. The windows of the building are elongated, and there is an intermediate floor level, whose detailed structure is metallic. A cleverly designed staircase, of folded sheet metal connects the ground floor, the intermediate floor level and the restaurant. Materials were carefully chosen in accordance with their function. The colour scheme has a sustained unity throughout the building, and care has been taken to avoid surprising or vivid chromatic patterns. Ceramic enamels by the painter Santiago del Campo provide a feature of decoration on the ground floor, and also serve to cover up the return air ducts. On the top floor, the restaurant is fitted with coloured tile facings, the work of the Seville painters Maria Josefa Sanchez, Maria Dolores Sanchez and Emilio Garcia Ortiz. The bottom joints of the timber beams, in conjunction with the tile patterns, is reminiscent of the traditional Sevillian habit of placing ceramic units between the timber framework of buildings. The initial problem of the architect was to combine the optimum functional efficiency and aesthetic quality of the project, and the final solution is undoubtedly successful.

XI. Observations on the Origin and Progress of Gothic Architecture, and on the Corporation of Free Masons supposed to be the Establishers of it as a regular Order. In a Letter from Gov. Pownall, to the Rev. Dr. Lort, V.P.

The following paper collects and puts together some scattered historic traces of the architecture used in the transalpine parts of Europe, in order from thence to suggest a line of inquiry after the origin of that particular species of it, called the Gothick; and also after the institution of that Collegium or corporation of Free-masons, whom I conceive to have been the first formers of this architecture into a regular and scientifick order, by applying the models and proportions of timber frame-work to building Stone.