124 research outputs found
Mecenazgo y edición en la primera mitad del siglo XVI: el Florindo de Fernando Basurto (Zaragoza: Pedro Hardouin, 1530)
Get PDFSe analizan las funciones del editor y del mecenas en la publicación de libros impresos en el siglo XVI. Para esto se estudia en profundidad la actividad de Fernando Basurto, autor, y de Juan Fernández de Heredia, mecenas-editor, en torno a la primera edición del Florindo publicado por Pedro Hardouin en Zaragoza en 1530.
The paper discusses the functions of the publisher and patron in the publication of printed books during the 16th Century. With this purpose, the activity of Fernando Basurto, author, and Juan Fernandez de Heredia, patron-editor, about the fi rst edition of Florindo published in Zaragoza by Pedro Hardouin in 1530 is studied
Modeling the influence of delamination on the mechanical performance of straight glued laminated timber beams
No full textDelamination at the glue lines is a key factor to take into account when assessing glued laminated timber members in service. In order to gain a more objective and wide knowledge about the importance of delamination in relation to its type and extension, a numerical study was developed.
Finite element modeling (FEM) was used to evaluate the influence of delamination – near the surface, on the vertical faces and ends – on the mechanic performance of straight glued laminated timber beams. The FEM was validated by comparing stresses and deformations obtained with the model and with the application of the beam theory, showing satisfactory results. Results show that when delamination is non-symmetric regarding the member’s cross section, it can cause the member’s lateral instability, thus increasing its stresses and deformations. Delamination is not a problem when it occurs in members or member areas with low shear stresses, particularly when it is symmetric and does not reach the whole width of the beam. The stresses corresponding to the bending or deformation limit-states get near the elastic limit only for very important delamination. Moreover, delamination depth higher than 60% of
the cross section width may be regarded as a turn point beyond which the structural integrity may be at risk.447-455ppThe authors wish to thank Fundação para a Ciência e a Tecnologia
(Portuguese Foundation for Science and Technology), for the PhD
grant (number SFRH/BD/30310/2006) given to Florindo Gaspar.98DE/NCEConstruction and building material
Mecenazgo y edición en la primera mitad del siglo XVI: el Florindo de Fernando Basurto (Zaragoza: Pedro Hardouin, 1530)
Get PDFThe paper discusses the functions of the publisher and patron in the publication of printed books during the 16th Century. With this purpose, the activity of Fernando Basurto, author, and Juan Fernandez de Heredia, patron-editor, about the first edition of Florindo published in Zaragoza by Pedro Hardouin in 1530 is studied. Se analizan las funciones del editor y del mecenas en la publicación de libros impresos en el siglo XVI. Para esto se estudia en profundidad la actividad de Fernando Basurto, autor, y de Juan Fernández de Heredia, mecenas-editor, en torno a la primera edición del Florindo publicado por Pedro Hardouin en Zaragoza en 1530.
NonDestructive Techniques for the Assessment and Preservation of Historic Structures
Get PDFThe preservation of the built heritage has long been a public concern, mainly due
to fears about the loss of identity, history and heritage of populations. The main
concerns are the conservation and restoration of monuments that usually represent
important events in the history of a city or a country. More recently, urban residents
and policymakers have become aware of the abandonment or degradation of old city
cores, leading to mischaracterisation of the buildings and ways of living.
To preserve history and promote building and urban renewal, considering the
basic principles of the preservation process, it is important to introduce the least possible
disturbance. To start with, the diagnostic process is a key aspect, especially to
investigate the construction characteristics and the damage to materials, and to find
structural and nonstructural problems.
To start any process, a visual inspection, a study and knowledge of the original
construction methods and materials and historical repair techniques can help but
may not be sufficient, and the use of conventional techniques to complement the
information needed can result in an insufficient understanding or in extensive and
unnecessary intrusions in the construction.
In recent years, the rapid growth of science and research, combined with the
industry and the need to gather more and accurate information, have led to the fast
development of nondestructive testing methodologies that allow the architectural
archaeology to be studied, the structural assessment to be supported and information
to be given about the material properties. Each technique can be used for a specific
purpose, but, in some cases, only a combination of techniques is reliable and gives
an accurate interpretation of the data acquired.
The fundamental contribution and aim of this book is to give a full overview of several
case studies where different nondestructive techniques have been applied, in several
cases using multidisciplinary approaches, which aim to highlight the importance
of the information acquired and encourage the use of these techniques in future studies.
The book brings together 16 chapters focused on nondestructive testing techniques
applied at the urban building level and also applied to monumental buildings,
archaeology and cultural heritage, bringing together more than 40 international
researchers and experts in the field, who are the source of practical case studies supported
by a theoretical background.info:eu-repo/semantics/publishedVersio
Avaliação da resistência de vigas de madeira lamelada colada de pinheiro bravo
Get PDFAo longo dos anos, têm sido desenvolvidos vários modelos para prever a resistência de
uma viga de madeira lamelada colada a partir das propriedades mecânicas das lamelas,
desde os empíricos aos numéricos estocásticos.
A presente dissertação pretende estudar se o uso de informação detalhada acerca das
propriedades mecânicas das lamelas permite com maior exatidão prever a resistência de
uma viga de madeira lamelada colada que outros modelos já existentes. Para estudar
esta hipótese, usou-se os dados provenientes de estudos anteriores de Gaspar (2006,
2010) sobre a viabilidade da aplicação de madeira de pinheiro bravo (pinus pinaster
Ait.) tratada com produto preservador em estruturas de madeira lamelada colada. Este
autor mediu o módulo de elasticidade longitudinal das lamelas em vários pontos, cujos
dados foram aplicados em modelos de elementos finitos 3D e foram sujeitos a
tratamento estatístico no presente estudo.
A modelação das vigas mostrou que, em vigas de lamelado colado de pinheiro bravo
sujeitas a flexão, se atinge a rotura na lamela exterior à compressão antes de a viga
romper na lamela exterior à tração.
Uma análise de componentes principais veio a mostrar que a presença de ligações de
entalhes múltiplos (LEM) nas zonas de maior tração é o fator mais condicionante e
limita significativamente a resistência de uma viga, constituindo um ponto mais fraco
que os defeitos da madeira. Este fenómeno agrava-se com a presença de tratamento
preservador na madeira, suspeitando-se que a cola usada tenha um papel na falta de
resistência das LEM.
A lamela exterior comprimida nas vigas de pinheiro bravo tem maior influência na
resistência da viga que o módulo de elasticidade da lamela tracionada, contrariando
alguns modelos que apenas consideram a lamela tracionada como sendo condicionante
para a resistência. Uma simulação de Monte-Carlo mostra que o uso da classificação visual da NP 4305
(1995) nas lamelas de pinheiro bravo resulta em vigas de lamelado colado com
resistência compatível com as classes de resistência da NP EN 1194 (2002)
Análise comparativa de soluções construtivas para edifícios
Get PDFO presente estudo visa a análise comparativa de diferentes sistemas de construção dos elementos estruturais e paredes exteriores de edifícios de pequena dimensão, nomeadamente moradias unifamiliares.
Atualmente existem no mercado diversos métodos construtivos alternativos ao tradicional (betão armado e alvenaria).
Para este estudo foram selecionados 4 métodos alternativos ao tradicional: dois deles mais comuns e com uma implantação significativa no mercado e os outros dois mais disruptivos e pouco conhecidos no mercado português, com um histórico ainda muito recente.
Assim sendo, os sistemas objeto deste estudo são o método Tradicional (betão e alvenaria), o LSF (Light Steel Framing - perfis metálicos estruturais isolados), o Woodframe (perfis estruturais de madeira isolados), o Sistema Fractus (painel estrutural isolado) e o Sistema Baupanel® (EPS armado + microbetão).
Para a avaliação do desempenho dos diferentes métodos construtivos nos vários atributos em análise foi efetuado um inquérito a várias entidades direta ou indiretamente relacionadas com a construção ou decisão de aquisição de um imóvel.
Para dois desses atributos- o Custo de construção e a Rapidez de construção-, foi selecionado o projeto de um edifício de pequenas dimensões (uma moradia com 140 m2 de implantação, com cave e piso térreo), que serviu de base à consulta a vários instaladores e construtores das diferentes soluções, no sentido de obter destes propostas comparáveis.
A realidade da construção de edifícios, não apenas em Portugal, mas de um modo geral em todo o mundo, sofreu um conjunto de alterações de contexto que justificam o momento de alteração de paradigma que se encontra a atravessar. De facto, este início de século, em especial no período pós crise financeira mundial de 2008, e agravado pelos episódios da pandemia Covid em 2020 e da guerra na Ucrânia em 2022, veio alterar em definitivo o xadrez da construção, nomeadamente a construção de edifícios.
Muitas foram as variáveis alteradas, nomeadamente a escassez de alguns recursos (mão de obra e materiais), o aumento dos preços generalizado, o funcionamento errático das cadeias logísticas, a maior sensibilização ambiental e preocupações energéticas, entre outras.
É neste contexto vivido em 2023 que se torna oportuna a análise de diferentes soluções construtivas
Limes with Hydraulic Properties for 3D Printing Mortars
Get PDFThe adoption of 3D printing in the global construction industry is still in its infancy, but the technology is already being used to build street furniture, bridges, and even multistory buildings. While this technology allows using fewer resources than some conventional construction processes, most of the printing-adapted mortars available on the market are cement-based, with a high mechanical performance that is suitable for many uses. But these mortars have a high ecological footprint and may not be the most suitable as interior finishes because they have low hygroscopicity and do not contribute significantly to regulating the relative humidity inside buildings. To address some of the concerns mentioned above, a 3D printing mortar was developed using limes with hydraulic properties, namely, hydraulic lime and natural hydraulic lime, as the main binder. The combination of fine sand, limestone powder, superplasticizer, viscosity modifiers, and setting accelerators allowed to achieve the required characteristics for a printing mortar. To develop the lime mortars, comparing them with conventional mortars used in the literature, extrusion tests were performed using a robotic arm and an auger extruder. Through the extrusion tests, it was possible to confirm that cement can be replaced by lime to build nonstructural elements. The study evaluates the change in workability over time. The proposed mortars exhibit very similar behavior, but over time they show different properties in comparison with the 3D ready-mix mortar. The buildability test shows that lime-based mortars can support self-height deformation as any cement-based mortars
Structures in Cross Laminated Timber – Technical/Economic Feasibility Analysis
No full textThe use of cross laminated timber (CLT) in building construction has gained significant attention in recent years due to its environmental benefits, ease of construction, and potential cost savings. In recent years, it has gained popularity as an alternative to traditional building materials. Although CLT structures have been successfully used in low-rise buildings, the potential use of his CLT in medium-rise buildings up to four storeys has been investigated.
This work evaluates the technical and economic feasibility of building a CLT structure with a rising number of floors using a project with an area of 242 square meters and a floor height of 3 meters.
The study included a comprehensive analysis of the design and construction of CLT structures for the one, two, three, and four floors. Technical feasibility was assessed based on the structural performance and serviceability of each of the CLT structures. The technical feasibility of the CLT structures with increasing number of floors was analyzed by evaluating the load-bearing capacity of the panels (wall and floor), connections and the entire system using robot analysis software and the CLTDesigner application.
Analysis shows that theses CLT panels can provide sufficient load-bearing capacity and stiffness for medium-to-high structures, and that the connections between panels can effectively carry various combinations of loads (dead load, live load, seismic load, wind load). It was shown that it can be designed to transfer loads effectively.
Moreover, cost analysis indicates that the initial cost of using CLT, especially the cost of materials, can be high. Advantageously, Long-term savings can be realized through reduced construction time and energy efficiency. Overall, the study concludes that CLT is a suitable building material for buildings up to four storeys high and is a sustainable and efficient alternative to conventional building materials
Web Application for Visualizing Emission Data from Construction Equipment
No full textPollutants produced by heavy diesel construction equipment account for significant amounts of emissions derived from construction operations. The European Union (EU) regulates threshold levels of emissions from heavy construction machinery, and in the past years, the use and need for sensor technologies to measure emission levels have increased. Concurrently, the Internet of Things (IoT) and Digital Twins (DT) have gained much attention in several industries. In the construction industry, research on DTs is still in its early stages and has focused mainly on the operational phase of buildings. The combination of Building Information Modelling (BIM) and IoT for visualizing data is considered promising for creating DTs. However, there is a lack of well-defined processes and methodologies, especially concerning the DT of construction sites. In response to the need to reduce construction emissions and advance construction DTs, this project demonstrates a preliminary web-based application for run-time data visualization of construction equipment emission levels (NOx, PM, and CO2) with BIM-based terrain modelling. A methodology is presented and discussed, covering the steps from data gathering to set up and use. Despite the complexity of the process and limitations encountered, early tests were satisfactory and showed potential for further development of a DT for the construction phase
Levantamento e caracterização das patologias da Capela do Fundador do Mosteiro da Santa Maria da Vitória
No full textO Mosteiro de Santa Maria da Vitória, mais conhecido por Mosteiro da Batalha,
é um dos mais belos exemplos de arquitetura em Portugal e na Europa, fazendo parte
da lista do Património Mundial da UNESCO desde Dezembro de 1983.
A sua construção levou 150 anos, ao longo de diversas fases e composto por
vários estilos: gótico, manuelino e uns toques de renascentista. Foram feitas algumas
alterações ao projeto inicial, resultando num grandioso e complexo Monástico que hoje
inclui uma igreja, dois claustros com divisões anexas e dois panteões reais, a capela do
fundador e as capelas imperfeitas.
O património construído reúne patologias e defeitos derivados da deterioração
dos materiais, cargas repetidas, falta de manutenção e eventos excecionais. Dentro
deste processo, as técnicas de inspeção e diagnóstico desempenham um papel
importante, fornecendo informações e permitindo a definição de medidas de reparação
adequadas.
Para iniciar este levantamento no Mosteiro de Santa Maria da Vitória a Capela do
Fundador foram efetuadas campanhas de inspeção não destrutiva, ou seja, a
termografia, teste ultrassónico, diagnóstico preliminar com mapeamento das
patologias, varrimento laser scanning e esclerómetro.
Verificaram-se diferenças significativas nos resultados obtidos com os ultrassons
e o esclerómetro segundo a orientação e patologias, que parecem estar associadas à
degradação superficial da pedra. Da análise do varrimento laser foram verificados
alguns deslocamentos horizontais da estrutura. Os resultados alertam para a
necessidade de monitorização do Mosteiro como meio de prevenir a sua degradação.
Da análise ao mapeamento, as crostas negras é a patologia mais comum na
Capela do Fundador e no Mosteiro em geral. A pátina é também uma patologia que
abrange a CF em larga escala
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