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Avaliação do desempenho térmico por análise termográfica de tintas refletantes aplicadas em fachadas com ETICS
No full textAvaliação do desempenho térmico de tintas refletantes aplicadas em células experimentais utilizando termografia de infravermelhosCIN8411DED/NRI20145 e 6 de junh
Reatividade potencial de rochas graníticas. Petrografia vs ensaios de expansão
No full textAs rochas graníticas representam em Portugal cerca de 40% do volume total de agregados para
concreto. Estas rochas são normalmente consideradas como sendo de reação lenta ou até como não
reativas aos álcalis. Contudo, diversos casos de reação álacalis-agregado (RAA) têm sido diagnosticados
em estruturas de concreto nas quais foram utilizadas rochas graníticas. Com o objetivo de diminuir a
incerteza na avaliação da reatividade potencial aos álcalis de granitos foi desenvolvido um projeto de
investigação no qual os resultados deste artigo se inserem. No âmbito deste projeto foram estudadas
trinta e uma amostras colhidas em diferentes regiões de Portugal, apresentando-se neste artigo os
resultados de oito dessas amostras. Os ensaios realizados incluem a caraterização petrográfica dos
agregados e ensaios de expansão de barra de argamassa e prisma de concreto. Conclui-se que o
conteúdo em quartzo microcristalino se correlaciona melhor com os resultados do ensaio em prisma de
concreto RILEM AAR-4.1 do que com os outros ensaios de expansão.307-321ppOs autores manifestam o seu agradecimento à Fundação para a Ciência e Tecnologia (FCT) pelo financiamento do Projeto IMPROVE (Ref: PTDC/ECM/115486/2009). A autora V. Ramos agradece à FCT o financiamento da sua bolsa de doutoramento (Ref: SFRH/BD/47893/2008). Os autores afiliados ao CGUP agradecem o suporte da FCT através do Projeto Estratégico (PEst-OE/CTE/UI0039/2011)1DM/NMMPolitécnica - Revista do Instituto Politécnico da Bahi
The evaluation of uncertainty in mass calibration: Possible approaches in a comparison study
No full text7ppConference Series 459 (2013) 012033CIC/NQMJournal of Physic
Galgamento do quebra-mar poente de Albufeira: Comparação entre o modelo numérico SPH e medições de campo
No full textOs modelos SPH (Smoothed Particle Hydrodynamics), baseados na formulação Lagrangiana das
equações da Dinâmica dos Fluidos, são uma opção atractiva para modelar escoamentos com superfície livre, pois
não necessitam de malha computacional, permitindo modelar fenómenos complexos, como a rebentação de ondas
e o galgamento. Neste trabalho apresenta-se o modelo numérico SPHyCE em desenvolvimento no LNEC e a sua
aplicação à determinação do galgamento no quebra-mar poente do Porto de Pesca de Albufeira (Algarve), no qual
foram realizadas as primeiras campanhas de medição de galgamento num quebra-mar em Portugal no âmbito do
projecto SPACE (Desenvolvimento e validação de um modelo SPH para aplicações a estruturas costeiras).
Apresenta-se a metodologia de acoplamento dos modelos SWAN, Bouss2D e SPHyCE, para modelar a
propagação das ondas do largo até ao quebra-mar, assim como as campanhas de campo. São analisados e
comparados os galgamentos obtidos com o modelo numérico e os medidos.40143-146ppDHA/NPE201424 a 26 de junh
Adaptabilidade e habitação
No full textContinuando a apresentar e comentar reflexões de projetistas e estudiosos sobre aspetos considerados estruturantes nas opções de organização dos espaços domésticos, ficamos em seguida com Amos Rapoport e, depois, com Christopher Alexander, entre opiniões de outros autores, privilegiando-se uma perspetiva que tenta aprofundar a grande diversidade de soluções potencialmente disponibilizadas e que propiciam uma vida doméstica mais adequada, agradável e estimulante.2 fig6 pInfohabitar, Ano X, n.º 472DED/NUTRevista Infohabita
Surface skin protection of concrete with silicate-based impregnations:Influence of the substrate roughness and moisture
No full textSilicate-based impregnations are often used to protect concrete against aggressive external actions. However, the understanding of several aspects concerning this type of impregnations is still rather Iimited,
incIuding the influence of the concrete substrate on their performance. This paper presents reslllts of an experimental study about O) the efficacy of silicate-based impregnations to protect concrete elements, and (ii) the inflllence of the concrete substrate's characteristics on the performance of such superficial protection. Concrete specimens with two different water/cement ratios (0.40 and 0.70) were produced and, prior to the application of the impregnation, were prepared following different procedllres that created O) three different surface roughnesses (no surface preparation, 160 bar water jet and needle scalers) and (ii) three different moisture contents (3.0%, 4.5% and 6.0%). The performance ofunprotected and protected concrete specimens was assessed by means of the following procedures, indicated in EN 1504-2 standard: O) product penetration depth; (ii) water absorption by immersion; (iii) abrasion resistance; Ov) impact resistance; and (v) bond strength. Results obtained show that the silicate-based impregnation was effective in improving the resistance to water penetration and abrasion resistance, but did not improve the resistance to impacto The surface roughness and the moisture content at the instant of the application of the surface protection proved to influence the performance of the impregnation product, however such influence was dependent on the property at stake.191-200ppVol 70 (2014)DM/NMOConstruction and Building Material
Microsystin-LR and natural organic matter removal by biologically active carbon filters
No full textMicrocystin-LR (MC-LR) occurrence in surface water bodies is a worldwide issue of increasing concern due to climate change/global warming and their resistance to conventional treatment. The biologically active carbon filters (BACs), where both adsorption and biodegradation take place, are a promising option for upgrading the treatment plants, but the synergistic effects occurring in BAC filters are a key to success and are yet to be fully understood.
This study addresses the effects of background natural organic matter (NOM) and empty bed contact time (EBCT) on BAC performance for MC-LR removal. Biodegradation was assessed in long-term lab runs and showed that: MC-LR biodegradation occurred only in the presence of biodegradable NOM; the biological activity was relevant for MC-LR removal by BAC, it minimized the BAC efficiency decay along the operation time and was higher for shorter EBCTs, i.e. higher loading rates of substrates and oxygen.414pDHA/NES201421 a 26 de setembr
Guidelines for improved operation of drinking water treatment plants and maintenance of water supply and sanitation networks
No full textEste registo pertence ao Repositório Científico do LNECProject PREPARED addresses the adaptation of the water sector to climate change effects. It has been anticipated that some of the impacts of climate change, such as rises in average temperature and sea level, will only become apparent after many years. However, climate change-driven events are already happening with increasing frequency and intensity. This is the case of extreme storm and rain events and heat, drought and cold periods, which may impact water and wastewater systems. Therefore, in addition to structural adaptations of infrastructures that may be implemented on a medium- to long-term basis, many urban water utilities also need to adapt rapidly to on-going climate change effects.
Diverse scenarios are available for each country and region. In addition, the same climate effects may impact the various sectors and utilities differently. On the other hand, certain climate change effects may impact the infrastructures of all urban water cycle sectors.
The adaptation of water utilities to climate changes has been tackled in PREPARED through sectorial and integrative approaches. The former, which comprised adaptation measures for drinking water supply, wastewater and stormwater systems, were addressed in several work packages. The outputs produced include corrective and preventive measures for drinking water treatment plants, and drinking water and sanitation networks. With this respect, state-of-the-art knowledge and outputs from various PREPARED tasks were integrated and developed in PREPARED deliverable D5.5.5 in the form of guidelines, whose objectives are to support the design and implementation of adaptation measures. Accordingly, the D5.5.5 guidelines herein summarized comprise four chapters:
Chapter 1 – Improved operation of drinking water treatment plants
Chapter 2 – Maintenance of water supply networks
Chapter 3 – Maintenance of wastewater networks
Chapter 4 – Operation and maintenance of stormwater systems
For the sake of practical usefulness, adaptation measures, as well as their supporting technologies, methods and tools, are schematically and concisely presented in the guidelines. These also specify supplementary sources of more detailed and comprehensive information, which, in addition to pertinent PREPARED deliverables, include outputs from projects CARE-W, DayWater, TECHNEAU, CARE-S and AWARE-P.4163pDHA/NE
Determination of Extreme Sea Levels along the Portuguese Coas t
No full textAbstract:
This work aims at determining extreme water levels associ
ated with different return periods
through the development and application of a circulation mo
del for tides and surges. The model
covers a large portion of the NE Atlantic, and has a res
olution of 250 m in the Portuguese shelf. The
model was extensively validated for tides, surges and extreme s
ea levels. In the Portuguese shelf,
RMS errors of tides are of the order of 5 cm, and the mo
del under-estimates extreme water levels by
about 10 cm. Simulation of water levels between 1979 and
2010, followed by a statistical analysis of
the results, provided the relation between return perio
ds and extreme levels along the Portuguese
coast. Results reveal the growth of extreme water level
s from south to north.151-154ppDHA/NEC201424 a 26 de junh
CO2 Concentration in day care centres is related to wheezing in attending children
No full textPoor ventilation at day care centres (DCCs) was
already reported, although its effects on attending children are
not clear. This study aimed to evaluate the association between
wheezing in children and indoor CO2 (a ventilation surrogate
marker) in DCC and to identify behaviours and building
characteristics potentially related to CO2. In phase I, 45 DCCs
from Lisbon and Oporto (Portugal) were selected through a
proportional stratified random sampling. In phase II, 3 months
later, 19 DCCs were further reassessed after cluster analysis
for the greatest difference comparison. In both phases, children’s
respiratory health was assessed by ISAAC-derived
questionnaires. Indoor CO2 concentrations and building characteristics of the DCC were evaluated in both phases,
using complementary methods. Mixed effect models were
used to analyze the data. In phase I, which included 3,186
children (mean age 3.1±1.5 years), indoor CO2 concentration
in the DCC rooms was associated with reported wheezing in
the past 12months (27.5 %) (adjusted odds ratio (OR) for each
increase of 200 ppm 1.04, 95 % CI 1:01 to 1:07). In phase II,
the association in the subsample of 1,196 children seen in 19
out of the initial 45 DCCs was not significant (adjusted OR
1.02, 95 % CI 0.96 to 1.08). Indoor CO2 concentration was
inversely associated with the practices of opening windows
and internal doors and with higher wind velocity. A positive
trend was observed between CO2 and prevalence of reported
asthma (4.7 %). Conclusion: Improved ventilation is needed
to achieve a healthier indoor environment in DCC.039ppDED/NAICIEuropean J Pedriat