Estudo do material terra usado nas construções em tabique na região de Trás-os-Montes e Alto Douro

O tabique é uma das técnicas construtivas tradicionais portuguesas que usa terra como material de construção. Um elemento construtivo em tabique é geralmente formado por uma estrutura de madeira revestida por um material de revestimento/enchimento à base de terra. Trás-os-Montes e Alto Douro é uma região de Portugal rica em edifícios antigos construídos com recurso a esta técnica. Este trabalho pretende divulgar esta técnica mostrando alguns exemplos de construções, auscultar o estado de conservação dessas construções e descrever o procedimento adoptado para a caracterização de edifícios antigos construídos em tabique. Para identificar/caracterizar o material de revestimento/enchimento à base de terra procedeu-se a um estudo laboratorial que incluiu a realização dos ensaios de análise granulométrica por peneiração húmida, de análise microscópica SEM (Scanning Electron Microscope) e de difracção de raio X, em amostras recolhidas em quatro municípios da região. Com base nos resultados obtidos é possível conhecer o tipo de material à base de terra usado nas construções em tabique nesta região, quer em termos de composição granulométrica quer em termos de composição mineralógica. Esta informação também auxilia a identificação de zonas de extracção de terra para futuros trabalhos de reabilitação de construções em tabique. Observou-se também que algumas amostras apresentavam minerais de calcite e de carbonato de cálcio o que indicia o uso de um ligante/estabilizante do tipo cal no material de revestimento/enchimento e atendendo a que estes tipos de minerais não existem naturalmente na região de Trás-os-Montes e Alto Douro

Construções em tabique na Região de Trás-os-Montes e Alto Douro

O Tabique é uma das técnicas construtivas tradicionais que usa terra como material de construção. Trás-os-Montes e Alto Douro é uma região rica em edifícios antigos construídos com recurso a esta técnica. Este trabalho pretende mostrar alguns exemplos deste tipo de construção, auscultar o estado de conservação e descrever o procedimento adoptado para a caracterização de edifícios antigos construídos em Tabique. Neste contexto, pretende-se divulgar a realidade existente nesta região, dar um contributo para o conhecimento desta técnica construtiva que usa materiais naturais, sensibilizar para a conservação e reabilitação deste tipo de edifícios

Survey on the main defects in ancient buildings constructed mainly with natural raw materials

Many of the existing buildings constructed mostly with natural raw materials, in European sites, are frequently lacking proper maintenance and, therefore, a high degree of de-gradation is verified in these buildings compromising their integrity and reducing their lifetime probability. Often in the rehabilitation or reconstruction of old buildings the solution adopted is the partial or integral demolition and substitution of several building components. The aims of this study are to describe the most common constructive solutions in Portuguese buildings con-structed with raw natural materials, to specify the principal problems that affect each building component, and to present possible solutions to correct each defect. This study is focused on the principal elements that compose the building structures in Portugal, including load-bearing walls, wooden floor and roof structures. The corrective solutions presented and studied privi-leges the adoption of materials and techniques similar and most compatible with the original ones

Study of the traditional tabique constructions in the Alto Tâmega region

Tabique constructions can be found almost everywhere in Portugal. In fact, it is one of the most used traditional building techniques using raw materials, such as earth and wood, particularly for interior partition walls. A tabique constructive element can be described as a timber structure, more or less complex and robust, filled and plastered in both sides by a composite earth based material. Trás-os-Montes e Alto Douro region is the northeast region of Portugal where the tabique heritage is very vast/the most significant. Tabique can be found in any kind of constructions, from the very simple rural dwellings to more important buildings and constructions, such as castles, villas, etc. Many of the existing tabique constructions present an advanced stage of deterioration, partially justified by the maintenance knowledge and practice that has been lost over time about these techniques and their rehabilitation procedures, due to the fast introduction of new materials in the construction. Considering this, research work has been developed with the main objectives of studying the building process of tabique construction elements, typifying dimensions of tabique walls and its components, and characterizing constitutive materials. Within this research project, it was intended to create a knowledge basis that can guide and stimulate future rehabilitation actions in this field. At the first stage, this study was developed at one of the six council associations of the Trás-os-Montes e Alto Douro region, namely the Alto Tâmega. A selected group of constructions, representative of the existing heritage in the region, were detailed studied. The results of their characterization can help to recuperate/recover the practice knowledge concerning this traditional eco-construction technique, supporting the rehabilitation of the existing construction heritage, but also its eventual application in new construction

Construção de tabique no Vale do Douro Sul

O tabique é uma técnica construtiva tradicional portuguesa que usa materiais naturais tal como a terra crua e a madeira. Geralmente um elemento construtivo de tabique é formado por uma estrutura de madeira que é revestida com terra crua. A terra tem um papel importante nestes elementos construtivos porque simultaneamente protege a estrutura de madeira e serve como material de acabamento. A região de Trás-os-Montes e Alto Douro corresponde à parte nordeste de Portugal e é rica em construções antigas de tabique. Grande parte destas construções apresenta um avançado estado de degradação. Este facto aliado à escassez de estudos científicos relativos a esta temática motivou a realização de um trabalho de investigação que se encontra em curso e que visa estudar este tipo de construção e de forma a dar um contributo para futuros trabalhos de reabilitação. Atendendo a que esta região é muito vasta foi necessário fasear o referido trabalho de investigação. Deste modo, subdividiu-se a área de trabalho em seis partes referentes às seis Associações de Municípios da região e que são as seguintes: Alto Tâmega; Terra Quente Transmontana; Terra Fria do Nordeste Transmontano; Vale do Douro Norte; Vale do Douro Sul e Douro Superior. O trabalho que se aqui se propõe é relativo à Associação de Municípios do Vale do Douro Sul e usa dez construções antigas de tabique como amostragem. Para o efeito, foi efectuado um levantamento dessas construções e uma recolha de amostras dos materiais construtivos para estudo laboratorial

Tabique constructions in the Municipalities Association of Terra Fria do Nordeste Transmontano

Tabique is one of the main Portuguese traditional building techniques which basically use natural and local building materials such as earth and timber. A tabique building component such as a wall is built up using a simple timber structure covered by an earth based mortar on both sides. The earth based mortar has an important role in this building system technology since it not only protects the internal timber structure but it also acts as finishing element. Meanwhile, earth has the advantage of being abundant, natural, local and recycled giving to this technique a special importance in the sustainability context. It has been noticed that this traditional building technique has an expressive incidence in the region of Trás-os-Montes and Alto Douro, Portugal. Taking into account that the Trás-os-Montes and Alto Douro region is very large, there was the necessity to divide it in to more manageable areas. The manageable areas are the six Municipalities Associations, which are: Alto Tâmega, Terra Quente Transmontana, Terra Fria do Nordeste Transmontano, Vale do Douro Norte, Vale do Douro Sul and Douro Superior. This research work is focused on the Municipalities Association of Terra Fria do Nordeste Transmontano. This, combined with the scarcity of scientific studies concerning this type of construction in this region, motivated this research work that uses some constructions as sampling and which is focused on an experimental study to identify the chemical and mineralogical composition of the coating material / filler used, the species of wood and the hardness of the nails

Construção de tabique nas Associações de Municípios da Terra Fria do Nordeste Transmontano e da Terra Quente Transmontana

O tabique é uma das técnicas construtivas tradicionais portuguesas que usa terra como material de construção. Um elemento de tabique é formado por uma estrutura de madeira revestida em ambas as faces por um material de revestimento/enchimento à base de terra, sendo este um material natural, ecológico, reciclável, económico e, como tal, um material de construção com grande potencial. A região de Trás-os-Montes e Alto Douro corresponde à parte nordeste de Portugal e é rica em construções antigas com este tipo de técnica construtiva. Este trabalho de investigação incide sobre as construções de tabique existentes nas Associações de Municípios da Terra Fria do Nordeste Transmontano (AMTFT) e da Terra Quente Transmontana (AMTQT) e está integrado num outro trabalho mais vasto que pretende estudar esta técnica construtiva em toda a região de Trás-os-Montes e Alto Douro. Uma vez que a região em causa é muito extensa, e que o estudo necessita de ser pormenorizado, houve necessidade de subdividir a zona de trabalho. As Associações de Municípios do Vale do Douro Sul (AMVDS), Vale do Douro Norte (AMVDN) e Alto Tâmega (AMAT) já foram estudadas neste contexto. Este trabalho que aqui se apresenta é relativo à AMTFNT e AMTQT, que incluem os Concelhos de Vinhais, Bragança, Vimioso, Miranda do Douro e Mirandela, Macedo de Cavaleiros, Alfândega da Fé, Vila Flor e Carrazeda de Ansiães, respectivamente. Com este trabalho pretende-se dar a conhecer esta técnica construtiva que usa essencialmente materiais naturais e locais, e sensibilizar a comunidade científica e a população em geral para a valorização e para a necessidade de conservação e de reabilitação deste tipo de edifícios. Para o efeito, foi realizado um levantamento exaustivo destas construções, uma recolha de amostras dos materiais construtivos mais representativos para estudo de identificação/caracterização experimental e um levantamento/caracterização das patologias mais frequentes.Tabique is one of the Portuguese traditional techniques that uses earth as a building material. An element of tabique is formed by a timber coated on both sides with a coating material / filler based on land, being a natural material, ecological, recyclable, economical and, therefore, a building material with great potential. The region of Trás-os-Montes and Alto Douro corresponds to the northeastern part of Portugal and it is rich in old buildings in which this building technique was used. This research work is formed on the existing tabique construction in the Associação de Municipios da Terra Fria do Nordeste Transmontano (AMTFT) e da Terra Quente Transmontana (AMTQT). It is integrated in an another one which has as main objective to study this traditional Portuguese building technique in the Trás-os-Montes e Alto Douro region. Since this region is very big and that the study demands detail, the working area had to be divide in six parts. The Associations of Municipalities of the Douro Valley South (AMVDS), Douro Valley North (AMVDN) and High Tâmega (AMAT) have already been studied in this context. This work concerns the AMTFNT and AMTQT. The main objectives of this research work are: to inform the scientific community and, in particular, the population for the urgent need of conservation and rehabilitation process that the existing tabique constructions of this region require, to build a data base of building aspects related to this traditional Portuguese building technique which is sustainable, to contribute for the knowledge of this technique and to give guidance for the future conservation works

Characterization of traditional tabique constructions in Douro North Valley region

Generally, the traditional building techniques uses natural and local building materials such as stone, woodand earth and, are associated to building procedures that requires small amount of energy consumption and release an expressive noxious gases to atmosphere. The development of green building techniques that help the building industry contributing to a much more sustainable world may be inspired on these traditional building techniques as models. Each sector of societies including ourselves should pay a bill for environmental damaging. Each construction should have as associated environmental damaging cost and the selection process of a construction design solution should also be done in a sustainable bases in which the environmental parameters should be clearly identified and quantified. The tabique is one of the main Portuguese traditional building techniques, which is based on raw materials as earth and wood. In general, a tabique wall is formed by a simple timber structure covered by an earth based material. Earth has an important role in this system because it protects the internal timber structure as well as is a finishing. The Trás-os-Montes e Alto Douro is the northeast region of Portugal and it is very rich in terms of tabique heritage construction. Meanwhile, the existing tabique constructions show a generalized advanced stage of deterioration. This aspect associated to the fact that there is still a lack of scientific studies done in this field motivated this research work, which its main objectives are to identify the building process of tabique elements and to identify/characterize the applied materials. It is intended to stimulate and to give guidance for future rehabilitation works in this field. Taking into account that this region has a large area, it was necessary to divide this work in six stages related to the six council associations, which are Alto Tâmega; Terra Quente Transmontana; Terra Fria do Nordeste Transmontano; Vale do Douro Norte; Vale do Douro Sul and Douro Superior. This work is focused on the council association of Vale do Douro Norte (Douro North Valley), and uses twelve constructions as study cases. This research work also intends to contribute for a better sustainable world by stimulating the applications of natural building materials and the reutilization of traditional building techniques which are environmental friendly

Tabique construction characterization in Douro North Valley, Portugal: a first step to preserve this architectural heritage

The tabique is one of the main Portuguese traditional building techniques, which is based on raw materials as earth and wood. In general, a tabique wall is formed by a simple timber structure covered by earth. Earth has an important role in this system because it protects the internal timber structure as well as is a finishing. The Trás-os-Montes e Alto Douro is the northeast region of Portugal and it is very rich in terms of tabique heritage construction. Meanwhile, the existing tabique constructions show a generalized advanced stage of deterioration. This aspect associated to the fact that there is still a lack of scientific studies done in this field motivated this research work, which its main objectives are to identify the building process of tabique elements and to identify/characterize the applied materials. It is intended to stimulate and to give guidance for future rehabilitation works in this field. Taking into account that this region has a large area, it was necessary to divide this work in six stages related to the six council associations, which are Alto Tâmega; Terra Quente Transmontana; Terra Fria do Nordeste Transmontano; Vale do Douro Norte; Vale do Douro Sul and Douro Superior. This work is focused on the council association of Vale do Douro Norte (Douro North Valley), and uses twelve constructions as study case

A new methodology for the characterization of mode II fracture of pinus pinaster wood

In this study, the End Notched Flexure (ENF) fracture test was used to obtain the mode II Rcurve of the Pinus pinaster wood in the RL crack propagation system. The test method was numerically and experimentally analyzed. In the numerical study, three (3D) and twodimensional (2D) finite element analyses were conducted to determine the mode II critical strain energy release rate (GIIc) and the respective R-curve. Firstly, the 3D analysis was performed in order to obtain the strain energy release rates distributions at the crack tip, and consequently, to identify the presence of spurious fracture modes that could affect the measured GIIc. The P-δ-a values determined from the 3D model were compared with the same values obtained from the 2D model. The main objective was to validate the 2D model, which is computationally less expensive. On the other hand, measurement of the crack length in the ENF test is quite difficult in wood because crack tends to close during propagation. To avoid this experimental problem a Compliance-Based Beam Method (CBBM), based on equivalent crack approach, is proposed. Moreover, this method does not require additional experimental tests to obtain the elastic properties. Experimental tests were also executed in order to verify the numerical results. The aim is to introduce the CBBM as a standard data reduction scheme in order to measure the GIIc value