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Portuguese forests are mainly composed of hardwoods, which represent 69% of the forest area in 2010, being Blue gum (Eucalyptus globulus Labill.) the most abundant species (26%). The suitability of Blue gum for structural applications was demonstrated in previous studies. However, the most common uses are still related to the pulp and paper industry as well as energy production, mainly due to sawing and drying issues. The present paper describes a preliminary study on the potential application of non-destructive tests and analytical methods to predict the most important mechanical properties of glued laminated timber (glulam) beams made of Blue gum. The potential of mixed beams made of Blue gum and poplar was also analysed. The longitudinal vibration method and the transformed section method were considered. A total of 11 non-finger jointed full-scale glulam beams (7 of Blue gum and 4 mixed) were manufactured in the laboratory and tested for modulus of elasticity and bending strength assessment. After the bending tests, the density and moisture content of the beams were determined, and the bonding performance was checked by delamination and shear strength tests. Correlation coefficients were established between the predicted values and the experimentally assessed mechanical properties, indicating a huge potential of the predictive methods used. The mechanical properties of non-finger jointed beams tested were above the typical values found in the literature for the most common hardwoods available in European forest.

Reducing the cement content of concrete is of paramount importance towards sustainability, since its production process is highly energy-consuming and delivers massive CO2 emissions to the atmosphere. In this paper, the bond behaviour between steel and stainless-steel reinforcing bars and Low Binder Concrete (LBC), produced with approximately one half and almost one fourth of the minimum cement content prescribed in the standards, is experimentally investigated. Results show the compactness of the mixture to be the main parameter controlling bond development, more than the mixture compressive strength as suggested in published results and standards. A more compact and denser mixture increases the contact surface between the reinforcing bars and concrete, improving friction between both. LBC mixtures with lowered cement content, up to almost one fourth of the minimum recommended, can be used without jeopardizing the bond strength of reinforcing bars. LBC mixturespromise to be a fitting approach towards greater sustainability in the concrete production sector.

Reducing the cement content of concrete is of paramount importance towards sustainability, since its production process is highly energy-consuming and delivers massive CO2 emissions to the atmosphere. In this paper, the bond behaviour between steel and stainless-steel reinforcing bars and Low Binder Concrete (LBC), produced with approximately one half and almost one fourth of the minimum cement content prescribed in the standards, is experimentally investigated. Results show the compactness of the mixture to be the main parameter controlling bond development, more than the mixture compressive strength as suggested in published results and standards. A more compact and denser mixture increases the contact surface between the reinforcing bars and concrete, improving friction between both. LBC mixtures with lowered cement content, up to almost one fourth of the minimum recommended, can be used without jeopardizing the bond strength of reinforcing bars. LBC mixtures promise to be a fitting approach towards greater sustainability in the concrete production sector.

Among biological agents, insect attacks may cause severe degradation of timber structuresin the service life of buildings which leads to lower mechanical performance and, thus, maintenanceproblems over time. Additionally, compression perpendicular to the grain always features a weak spotwith respect to the long-term mechanical performance of timber members and joints. In the presentwork, the respective strength and elastic modulus were thus investigated for insect deterioratedwood. Following a standardized geometry, small samples degraded by anobiids were extractedfrom beams made of sweet chestnut wood (Castanea sativa Mill.) that were removed from service.Visual assessment of the external wood surfaces was then performed to identify areas infested byinsects. Afterwards, destructive monotonic compression tests were carried out perpendicularly tothe grain on the damaged area to determine the loss of compressive strength and elastic modulus.The experimental results showed that the loss of compressive strength and elastic modulus mightbe linearly correlated to the wood density loss for small samples infested by insects. Nonetheless,future work should focus on determining accurately the density loss in the insect-deteriorated partthrough non- or semi-destructive tests, in order to establish stronger relationships with the mechanicalproperties loss investigated.

In the present work, and for the first time, totally biosourced low-density particleboardswere produced using cardoon particles (a no added value by-product from the Portuguese cheese making industry), bound with a potato starch adhesive. Different starch/cardoon ratios (0.6, 0.8, 1 and 1.2) were tested and the effect of different bio-based additives (chitosan, wood fiber and glycerol) on the performance of the adhesive system was evaluated. The best result was obtained for a formulationwith a starch/cardoon mass ratio of 0.8, a chitosan/starch mass ratio of 0.05 and a water/starch mass ratio of 1.75. The particleboards produced had a density of 323 kg-m-3, internal bond strength of 0.35 N.mm-2 and thickness swelling of 15.2%. The values of density and internal bond strength meet the standard requirements of general-purpose lightweight boards for use in dry conditions according to CEN/TS 16368 specification. Moreover, the susceptibility of the formulations with best results was established against subterranean termites and one decay fungi.

There is a need for new solutions in wood protection against marine wood borers andtermites in Europe. A new solution could be the esterification of wood with sorbitol and citric acid(SCA) since these are inexpensive and readily available feedstock chemicals and have shownprotective properties against fungal wood degradation in earlier studies and preventedmacrobiological degradation, as shown in this study. Protection of wood products in the marineenvironment lacks available wood preservatives that are approved for marine applications. Termiteinfestation is opposed mainly by biocide treatments of wood. Several wood modification systemsshow high resistance against both marine borers and subterranean termites. However, the existingcommercialized wood modification products are costly. Both macrobiological forms of degradationrepresent a great threat for most European wood species, which are rapidly and severely degradedif not properly treated. This study investigated esterified wood in standard field trials againstmarine wood borers, and against subterranean termites in laboratory trials in a no-choice and choicetest. The treatment showed good resistance against wood borers in the marine environment afterone season and against subterranean termites in the laboratory after eight weeks. The low termitesurvival rate (SR) in the no-choice test during the first week of testing indicates a mode of actionthat is incomparable to other wood modification treatments.

Due to its average mechanical properties, poplar, a fast-growing species, has been disfavored compared to stronger species for several decades. Wood-based products may help changing that perspective and thus, poplar has been gaining its marketshare for structural uses. A state-of-the-art review concerning the use of poplar to produce glued laminated products, with special focus on the use of Portuguese poplar, is presented. The Portuguese forest produces a great variety of species. Themost common poplar species found in this country are Populus x canadensis, P. nigra L., and P. alba L. Despite its limited availability, and the market hesitation on its structural application, recent studies on poplar grown in the Portuguese forestshowed its suitability for structural purposes. Glued laminated timber (GLT) beams made with this species revealed a very promising mechanical behavior. Bending strength tests evidenced a ductile behavior on more than 70% of the beams, whichmotivated deepening the study on the raw material used to produce those beams. To predict the mechanical behavior of such beams, a 3D numerical model was developed. The numerically predicted results were compared with the experimental ones,showing very good agreement between both approaches.

O betão com baixa dosagem de ligante (LBC - low binder concrete na denominação anglo-saxónica) e o betão com baixa dosagem de cimento com agregados reciclados (LCRAC - low cement recycled aggregate concrete ) são alterativas eco-eficientes ao betão de cimento Portland com agregados naturais por apresentarem um menor impacto ambiental. Para contribuir para o estudo da viabilidade de aplicação estrutural do LBC e do LCRAC, apresentam-se neste artigo os resultados obtidos numa campanha experimental de ensaios de arrancamento (pull-out tests), realçando o desempenho obtido ao nível da relação entre a tensão de aderência e o deslizamento do varão de aço. Os resultados experimentais foram comparados com as propostas de previsão existentes e apresenta-se uma primeira proposta de lei para descrever a relação tensão de aderência-deslizamento, considerando a compacidade, os agregados reciclados, o diâmetro do varão e a respetiva área relativa das nervuras transversais. A influência positiva da compacidade na aderência foi validada através da comparação dos resultados obtidos com os resultados decorrentes da proposta existente no Model Code 2010.

In this article, an assessment method toestimate the residual strength of pine structural ele-ments degraded by anobiids is presented. This novelmethod was developed in the laboratory to be usedin situ and is based on the strength required to withdrawa screw on the surface of degraded timber. Samples ofdegraded maritime pine (Pinus pinaster Ait.) weresubmitted to micro-computed tomography (l-XCT) toquantify density loss. This parameter is highly corre-lated with mechanical properties thus central for theassessment of timber structural capacity. Density lossvalues have been correlated with both screw withdrawalforce and shear parallel to the grain strength showingsignificant relationships between these parameters.Using these correlations, the density loss of a degradedelement and its shear strength parallel to the grain viathe screw withdrawal force can be estimated enabling avalid quantitative assessment of the timber elementsresidual strength and, therefore, contributing to reduceunnecessary replacement, to boost eco-efficient inter-ventions and to provide foundations required to performexperimental modelling tests.

O risco refere-se à probabilidade de ocorrerem danos causados pela manifestação de um determinado perigo, sendo função da perigosidade, da exposição (de pessoas e bens) e da vulnerabilidade dos elementos expostos face a esse perigo.Um componente essencial da avaliação do risco è a análise da perigosidade associada aos perigos identificados num dado território, sejam de origem natural ou decorrentes da ação humana. Outro componente essencial é a análise dos elementos (pessoas e bens) expostos aos perigos, bem como as características que contribuem para a suavulnerabilidade - ou a sua resiliência em situação de acidente grave ou de catástrofe. Nesta comunicação dá-se conta de alguns estudos desenvolvidos pelo LNEC nos domínios da avaliação da perigosidade e da vulnerabilidade sísmica das construções, da perigosidade de agitação costeira e risco de galgamentos costeiros e da avaliação da vulnerabilidade de edifícios aos incêndios florestais.

As ligações com ligadores do tipo cavilha sujeitos ao corte são estruturalmente eficientes e vulgarmente utilizadas em estruturas de madeira. À temperatura normal o comportamento das ligações condiciona fortemente o desempenho das estruturas que integram e em cenário de incêndio a sua importância é ainda maior, devido à redução das secções de madeira para colocação dos elementos metálicos, que por sua vez promovem a condução de calor para o interior dos elementos de madeira.O objectivo desta comunicação é apresentar o actual método de cálculo da resistência ao fogo adoptado na Europa, segundo a EN 1995-1-2, de ligações em madeira com ligadores do tipo cavilha ao corte

Foi realizado um programa experimental tendo em vista avaliar o desempenho da madeiralamelada colada (glulam) de pinho bravo tratado com um produto preservador de azóis de cobre.A resistência das juntas coladas cumpriu os requisitos da norma EN 386 (2001) sem influência da pressão de aperto e da temperatura de cura. Segundo a mesma norma, a delaminação foi satisfatória para as temperaturas de cura mais elevadas aplicadas com uma pressão de aperto de 0,6 N/mm2. As ligações de entalhes múltiplos fabricadas com madeira tratada apresentaram resistência satisfatória à flexão. O tratamento preservador não influenciou o módulo deelasticidade das vigas. Segundo uma simulação de Monte Carlo realizada e de acordo com os requisitos da norma NP EN 1194 (2002), é possível fabricar madeira lamelada colada da classe GL 28c se for usada madeira de Pinho bravo classificada visualmente nas classes E e EE (NP 4305, 1995) nas lamelas interiores e extremas, respectivamente, e da classe GL 24h quando forem usadas ambas as classes em proporções iguais aleatoriamente distribuídas pelo elemento estrutural. A study was conducted to evaluate the performance of glued laminated timber (glulam) of maritime pine treated with a copper azole preservative product. Shear strength of glue lines met the requirements of EN 386 (2001) with no influence of clamping pressure and cure temperature.According to the same standard, delamination was satisfactory for higher cure temperaturesapplied with a clamping pressure of 0,6 N/mm2. Finger joints made with treated wood presented satisfactory bending strength. The preservative treatment did not influence the modulus of elasticity of the beams. According to a Monte Carlo simulation and following the requirements of EN 1194(2002), glulam of class GL 28c can be manufactured if visually graded maritime pine of classes E and EE (NP 4305, 1995) is used in the inner and outer lamellas, respectively, and class GL 24h when using both grades in equal proportions randomly distributed through the glulam element.

A utilização e comercialização de lamelados colados têm tido um aumento significativo na última década em Portugal. No entanto a produção de lamelados, devido a condicionalismos de fabrico, é sustentada na utilização de madeiras de Resinosas que apresentam em geral uma baixa durabilidade natural.De forma a potenciar a utilização de lamelados colados em situações de classe de risco 3 ou 4, foi levado a cabo um estudo com o objectivo de avaliar a possibilidade de tratamento de lamelados colados com creosote.Esta possibilidade foi estudada através da impregnação com creosote de três tipos de lamelados (diferenciados quanto à espécie de madeira e cola utilizada), sendo avaliado o efeito do tratamento na qualidade da colagem (delaminação e resistência da junta colada). Foi igualmente efectuada uma avaliação preliminar da eficácia do tratamento atendendo à constituição do lamelado colado.Os resultados obtidos permitem concluir da possibilidade de realização do tratamento, sendo, no entanto, crucial um controlo apertado da qualidade de fabrico de forma a garantir a qualidade pretendida das juntas coladas e a durabilidade biológica dos lamelados. The use of glued laminated timber, have shown a significant increase in the last decade in Portugal. However glulam production due to manufacture constraints is sustained in the use of softwoods that generally show a low natural durability.In order to evaluate the behavior of glued laminated wood intended for use in exterior conditions (hazard classes 3 or 4), a study was carried out to evaluate the possibility of treatment with creosote, at an industrial scale.The study included several solutions of glued laminated timber intended for exterior conditions.The solutions differ in relation to the wood species and type of glue used in their manufacture.The results obtained allow concluding that the use of glued laminated timber is technically feasible, even though a close control of the manufacturing quality is necessary to ensure the desired quality and durability of the laminated timber.

Comparam-se as duas normas portuguesas sobre execução das estruturas de betão

Apresenta-se o trabalho experimental desenvolvido com a finalidade de conhecer a capacidade mecânica em flexão de provetes de 340 x 20 x 20 mm de madeira de pinho bravo(Pinus pinaster, Ait.) degradados por fungos de podridão, submetidos a tratamento por umproduto biocida e a consolidação por um consolidante polimérico de baixa viscosidade.

A caracterização do perfil nervurado das armaduras utilizadas é, actualmente, a maneira mais simples de medir o desempenho das armaduras em termos de aderência, nomeadamente através da definição da área relativa das nervuras transversais (fR). Por outro lado, é sabido que é fundamental conhecer as condições de aderência para quantificar de forma correcta o deslizamento que efectivamente ocorre na interface entre o betão e a armadura.Este fenómeno reveste-se de especial interesse nas zonas de ligação viga-pilar sujeitas à acção sísmica, uma vez que existe um acréscimo de rotação que está associado ao deslizamento que ocorre entre as armaduras que atravessam a ligação e o betão envolvente. Neste contexto considera-se fundamental descrever o fenómeno da perda de aderência com a maior exactidão possível, para que seja possível obter estimativas realistas do comportamento das estruturas. Este tipo de abordagem enquadra-se no chamado Performance-Base Earthquake Engineering (PBEE), uma vez que nas filosofias mais recentes relativas ao dimensionamento sísmico de estruturas, se admite que se devem considerar explicitamente múltiplos objectivos de desempenho para as estruturas sendo necessário um conhecimento muito mais detalhado dos fenómenos e das características dos materiais.Na presente comunicação apresenta-se a análise estatística das características geométricas do perfil nervurado dos varões do tipo A500NR SD, realizada com base nos resultados dos ensaios de medições de nervuras executados pelo Laboratório de Ensaios de Produtos Metálicos do LNEC. A análise é feita em função das diversas grandezas que permitem quantificar a área relativa das nervuras transversais e dos diâmetros ensaiados, sendo também feita uma comparação sistemática com os valores de referência.

ABSTRACT: This paper describes the results obtained on glued laminated timber beams of maritime pine, with andwithout preservative treatment, exposed to natural outdoor environment as well as to artificial weathering. Theassessment of glue lines

When timber elements in heritage buildings are moderately degraded by fungi and assuming underlying moisture problems are solved, two actions can be taken: i) use a biocid product to stop fungi activity ii) consolidate the degraded elements so that the timber keeps on fulfilling its structural and decorative functions. This paper presents the laboratory work performed with the purpose of understanding the mechanical performance of maritime pine timber degraded by fungi when subjected to a treatment with a biocid product followed by consolidation with an impregnationproduct. Three commercially available pre-selected products were used: a boron water-based biocide, an acrylic consolidation and an epoxy based consolidant. Treated and consolidated specimens were subjected to mechanical tests: axial compression test and surface hardness. Similar sets of replicates were subjected to an evaporation aging test after the products were applied and equally tested. An increase in mechanical strength was observed for both consolidants with no significant influence of the previous use of biocode product. The specimens subjected to aging showed a slightly better general mechanical performance than those not aged.

The present paper concerns the theme of maintenance/rehabilitation of timber structural elements in heritage buildings that have been degraded by rot fungi. This type of degradation usually results fromthe unwanted but continuous presence of water in timber elements, very frequently permeating through damaged roofs and facades. In the past, it was common practice to replace degraded timber with new elements of the same or similar material. However, the option of maintaining in the buildingthe original timber (even though deteriorated) has gained considerable importance in recent years.Therefore, a research programme on the consolidation of timber through impregnation of polymericproducts is under development, looking for ways to regain the former original physical andmechanical conditions. This technique has been largely used in restoration of works of art but verylittle in civil engineering. The laboratorial work, developed using degraded maritime pine specimens, is presented. The test-specimens were either prepared in the laboratory, at different decay levels by varying the exposure time to brown-rot fungi. Six commercial low-viscosity products, specific for the impregnation of timber deteriorated by rot fungi, were tested: four epoxy-based (R, E, Lw, Li) and two acrylics (PB72, B98). The efficiency of these products was assessed through compression testsparallel to the grain and hardness tests, involving both impregnated and non impregnated wood. The relationships between the level of degradation of the timber (mass loss), the penetration capacity ofthe polymer and the consolidation efficiency on test-specimens are presented and discussed. Test results indicate a reasonably good strengthening effect of some of the products tested, the best valuebeing a 39% increase in compressive strength and 91% increase in surface hardness by comparison with timber under the same circumstances but not consolidated.

Wood preservation has become increasingly important in the last years due to the scarcity of high quality wood since wood preservation can enhance wood life time, and improve some of its properties. However the use of toxic chemicals has been a major concern. Wood modification is an ecological way to improve mainly dimensional stability and durability of wood without harmful chemicals. Several wood modification processes have emerged in the last few years, the most important being thermal, chemical, surface and im¬pregnation modification. Furfurylation is considered the most important impregnation process with promis¬ing perspectives, since furfuryl alcohol can be obtained from secondary products of bioethanol production, and its price shows a tendency to lower in a near future.Sapwood pine boards [Pinus pinaster Aiton) were treated with a furfuryl alcohol mixture [FA 70 mix] at Kebony [Norway). The treatment was carried out in an autoclave with a vacuum and pressure stage and subsequently cured and dried in a vacuum drying kiln. Equilibrium moisture content, radial, tangential and volumetric dimensional stability measured as anti-shrinking efficiency between 35% and 85% relative hu¬midity [ASE35-85], and durability to brown rot [Postia placenta] and wet rot fungus [Coniophora puteana] were determined.Equilibrium moisture content [EMC] of furfurylated pinewood decreased from 9% to 5% [at 35% relative hu¬midity] and from 17% to 9% [at 85%], corresponding respectively to 43% and 48% improvement in relation to untreated wood. Dimensional stability improved for furfurylated wood with radial, tangential and volumetric ASE35-85 of 26.1 %,46.7% and 46.4%, respectively. Mass loss due to wood decay decreased from 29.2% to 1.1 % for brown rot [Postia placenta] and from 5.7 % to 0.8% for wet rot [Coniophora puteana).

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O Museu da Academia das Ciências de Lisboa possui uma preciosa xiloteca assinada pelo Mestre dos marceneiros portugueses, José Aniceto Rapozo contendo 1213 amostras de madeiras do Brasil e 12 de outras origens. A sua importância no progresso do conhecimento dos recursos florestais do Brasil naviragem dos séculos dezoito e dezanove conduziu ao estudo em curso. Dada a devastação verificada em vastas áreas florestais brasileiras, surgem dificuldades por certas espécies poderem ter distribuiçãogeográfica diferente (com eventual extinção, geral ou localizada), por insuficiência do material de comparação, e por ambiguidade das designações comerciais.Foi possível identificar esta xiloteca como uma de quatro encomendadas a Aniceto Rapozo pelo Príncipe Regente. A análise das amostras de madeira e a informação documental mostram que a colecçãotem por base uma remessa de 5008 amostras de madeiras do Brasil enviada em 1784 para o Arsenal Real do Exército, em Lisboa, pelo Vice-Rei do Brasil, Luís de Vasconcellos e Souza.O valor científico do conjunto é evidenciado pela identificação botânica das espéciesrepresentadas. Na situação actual, a identificação das espécies florestais representadas na amostragem foiinteiramente conseguida em 14% dos casos, conseguida mas ainda por confirmar em 27%. Dado o carácter preliminar deste estudo, os seus resultados serão ulteriormente publicados com mais pormenor. Among the Lisbon Academy of Sciences Museum collection there is a valuable xylarium by theleading Portuguese master cabinet-maker José Aniceto Rapozo (1756-1824), comprising 1213 wood samples from Brazil plus 12 from elsewhere. This collection is most important since it allows us to improve the knowledge on Brazilian forest resources by the end of the eighteenth century and thebeginning of the next. This study aims to establish its historical framework and scientific value. Owing tooverexploitation and even devastation of very large forest areas in Brazil, difficulties for our study aroseeither as some species may have now a different geographical distribution (and eventually may have underwent local or general extinction), by lack of adequate comparison material, or because of ambiguityof the commercial names.Results so far obtained allowed us to recognize the xylarium as one of the four commanded Rapozo by the Regent Prince, later King João VI (1767-1826). Taking into account the wood samples analyses as well as bibliographic data it is possible to conclude that the collection was prepared from a set 3 of 5008 Brazilian wood samples sent to the Royal Arsenal in Lisbon in 1784 by the Brazil

This work collects information about laboratory tests to evaluate the properties of agro-industrial wastes used for thermal insulation building materials considering them individually and in composits. It focuses on bio-susceptibility, as one of the main aspects to consider for bio-based building products.

Innovation in structures and construction materials demands a more accurate performance analysis during the life cycle. In addition, climatic changes pose new challenges to civil infrastructures that were not so relevant in the past. In most cases, the traditional test methods cannot accurately assess the complex phenomena involved in durability. The modern and complex factors require a different approach to durability analysis. The purpose of this chapter is to present innovative durability tests on construction materials: wood; rammed earth, cob and unfired blocks; natural stone; bituminous binders and mixtures; and Fibre Reinforced Polymers (FRP) to concrete bonded connections. Most of these tests concern the accelerated simulation of the main phenomena involved in durability performance

Laboratory tests were carried out to define production parameters of innovative eco-efficient composites made up of hazelnut shells as aggregate and a sodium silicate solution as adhesive. The aim was to maximize the content of bio-aggregates and minimize the amount of adhesive, guaranteeing the feasibility of producing samples. Therefore, after preliminary testing, the percentages of hazelnut shells and the sodium silicate solution were kept constant: 70% and 30% of the total volume, respectively. However, the characteristics of the considered composites did not allow the production of uniform samples. The sodium silicate solution was not rapidly absorbed by the bio-aggregates; during the drying process, it was deposited on the bottom side of the samples. The uniformity of the samples is required to guarantee a correct evaluation of their performance and future homogeneous panels. Hence, different production parameters were investigated, such as drying at T

The durability of construction materials is a key concern and can be related to different actions such as weathering conditions outdoors enhanced by climatic change, chemical and biological attack, abrasion, and other conditions of service over time. Frequently, several actions develop simultaneously, making it difficult to reproduce in situ conditions in laboratory. Furthermore, testing to assess durability depends largely on the nature of the material itself or on the way it has been assembled with other materials. The ageing techniques to assess long-term durability performance of construction materials are based on accelerated durability tests, which include, for example, thermal stress, freeze

This paper presents an overview of research carried out to assess the bonding suitability of Portuguese timbers.Most work developed in the last decades has focused Maritime pine timber, due to its traditional use in building construction, good mechanical properties and availability. Untreated, as well as preservative treated Maritime pine have been studied, as its impregnability allows deep treatment suitable for applications in Use Classes 3 and 4.Recent results on bonding preservative treated Maritime pine wood are discussed.Preliminary results regarding other species that are becoming available in the Portuguese market are also presented, as an attempt to reduce pressure on Maritime pine timber as well as to seek more valuable alternatives for their traditional uses.

No presente trabalho apresentam-se os resultados mais relevantes obtidos num programa experimental desenvolvido no LNEC com o objetivo de caracterizar a aderência dos varões nervurados do tipo A500NR SD existentes no mercado, fundamentalmente para melhorar a modelação do comportamento dos elementos de betão armado de zonas críticas de estruturas inseridas em zonas sísmicas.O programa experimental desenvolvido pretende simular as condições de aderência existentes num varão horizontal de uma ligação viga-pilar e tem como principais variáveis varões de dois diâmetros frequentemente utilizados (16 e 25 mm), dois níveis diferentes de área relativa das nervuras (A e B) e duas classes de betão (C1 e C2), ambos representativos do betão utilizado nas construções mais relevantes.Os resultados obtidos quer nos ensaios monotónicos quer nos ensaios cíclicos apontam para um decréscimo da tensão de aderência com o aumento do diâmetro da ordem dos 10%. O aumento da área relativa das nervuras transversais traduz-se num incremento da tensão máxima de aderência da ordem dos 15%, com uma redução do deslizamento que ronda os 15%. Nesse sentido, este estudo propôs que, no caso dos varões com maior área relativa das nervuras, a tensão de aderência máxima possa variar entre 2,35 e 2,65 vezes a raiz quadrada da resistência do betão à compressão e que o patamar onde a tensão de aderência é máxima se situe entre 0,5 e 1,5 mm de deslizamento.Explorou-se também o fenómeno da entrada em cedência da armadura tendo-se concluído que, em provetes que pretendem simular as condições de aderência existentes num varão horizontal de uma ligação viga-pilar, a entrada em cedência da armadura conduz a uma redução da tensão de aderência máxima inferior a 10%, quer regime monotónico quer em regime cíclico.

O presente trabalho de investigação refere-se à conservação de elementos estruturais de madeira medianamente degradados por fungos em edifícios antigos. Propõe-se estudar a compatibilidade entre produtos de tratamento e de consolidação por impregnação, aplicados sequencialmente. A avaliação do processo foi realizada maioritariamente em laboratório e na óptica do desempenho mecânico conjunto da madeira e produtos aplicados, por intermédio de ensaios físico-mecânicos destrutivos e não destrutivos e também por ensaios mecânicos não destrutivos realizados in situ. Foram utilizados produtos comerciais, aplicando-os às espécies de madeira correntemente encontradas nos edifícios antigos da zona de Lisboa: Pinho bravo e Casquinha. Procedeu-se à avaliação mecânica de madeira nova e antiga, em estado são e degradado; ao desenvolvimento de um método de medição da profundidade de penetração de produtos de tratamento; à avaliação da capacidade consolidante de madeira degradada por produtos poliméricos fluidos e à avaliação da sua actuação conjunta, estudada com e sem envelhecimento artificial. Os resultados obtidos indicaram significativos aumentos de capacidade mecânica da madeira degradada, quando submetida a tratamento e consolidação Este trabalho desenvolve, assim, uma proposta de solução para a madeira que não se encontra sã, mas que ainda possui capacidade resistente, não necessitando, por isso, de ser removida. O processo de tratamento e consolidação promove resistência aos agentes biológicos e, simultaneamente, recuperação de alguma resistência mecânica da madeira, conferindo-lhe capacidade para continuar em serviço.

Subterranean termites from the genus Reticulitermes are an important pest ofwood in service throughout southern Europe and elsewhere. For effective termitecontrol with long term protection but minimal environmental damage, newintegrated approaches to termite management are needed. Baiting-based systemsseem to be promising non-traditional methods for termite control, targeting thecolony as a whole. However, control through baiting is only feasible when it isknown that the toxicant can be transferred to all the colonies foraging on theinfested area and also throughout each individual colony. Accordingly, the workdescribed is specifically designed to achieve a better understanding of thedistribution and delimitation of colonies within a population of Reticulitermes,with parallel insights into foraging behaviour and colony organization.Initially, the species/subspecies spectrum present within the notionalReticulitermes group in Portugal was reassessed. It was shown that Reticulitermesgrassei is the only species encountered. Foraging activity was then assessed in anexperimental woodland site over two successive annual cycles, both by thesampling of natural lying dead wood and by a standard baiting grid. R. grasseiseem to select wood with larger diameter, with an apparent preference for materialalready decayed by fungi. Both termite and fungal attack on wood seems to bepromoted by higher moisture levels, such as prevail in larger litter items andduring seasonal rains. Termites were unable to detect and direct their foragingtowards sound wood in laboratory conditions, suggesting that the network ofinfochemical signals is more complex than just volatiles emanating from soundwood. Mark-release-recapture (MRR) was used to delineate foraging groups,which were then allocated to their parent colonies by the use of microsatellitemarkers. The results suggest that resource sharing is a facultative behaviour,specifically when food is not a limiting factor for colony development. Theimplications of all these findings for bait technology and protocols are discussed,with reference to the local population ecology of Reticulitermes.

The project CircularBuild -

Relatório final do projeto PTDC/ECM/099121/2008

O presente trabalho apresenta um projecto de versão portuguesa da Norma Europeia EN 10002-2, e insere-se numa série de estudos programados pelo autor, enquanto coordenador da normalização nacional no domínio dos ensaios mecânicos, físicos e não-destrutivos de materiais metálicos.O texto do projecto de norma apresentado consiste na versão final de uma proposta redigida pelo autor, na sequência dos estudos efectuados ao nível da Comissão Técnica de Normalização competente.

O presente trabalho apresenta um projecto de versão portuguesa da Norma Europeia EN 10002-5, e insere-se numa série de estudos programados pelo autor, enquanto coordenador da normalização nacional no domínio dos ensaios mecânicos, físicos e não-destrutivos de materiais metálicos.O texto do projecto de revisão apresentado consiste na versão final de uma proposta redigida pelo autor, na sequência dos estudos efectuados ao nível da Comissão Técnica de Normalização competente.

O presente relatório descreve a participação do LNEC no programa europeu de intercomparação de calibrações de forças

O presente trabalho apresenta um projecto de revisão da Norma Portuguesa NP 850 (1985)

O presente trabalho apresenta um projecto de revisão da Norma Portuguesa NP 386 (1965)

O presente trabalho apresenta um projecto de revisão das Normas Portuguesas NP 449 (1966)

O presente trabalho apresenta um projecto de revisão da Norma Portuguesa NP 450 (1966)

O presente trabalho apresenta um projecto de Norma Portuguesa relativo ao ensaio de dilatação de anéis de tubos metálicos, e insere-se numa série de estudos programados pelo autor, enquanto coordenador da normalização nacional no domínio dos ensaios mecânicos, físicos e não-destrutivos de materiais metálicos, com a finalidade de preencher lacunas da Normalização Portuguesa neste domínio que a indústria e as instituições ligadas ao controlo da qualidade considerem ser mais urgente colmatar.O texto apresentado consiste na versão final de uma proposta redigida pelo autor, na sequência dos estudos efectuados ao nível da Comissão Técnica de Normalização competente.

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