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Characterization tests for insulation boards made from corn cob and natural glues
No full textIn recent years there has been a growing interest in developing news solutions for more ecologic and efficient construction, including natural, renewable and local materials, thus contributing in the search for more efficient, economic and environmentally friendly construction. Several authors have assessed the possibility of using various agricultural sub products or wastes, as part of the effort of the scientific community to find alternative and more ecologic construction materials.
Corn cob is an agricultural waste from a very important worldwide crop. Natural glues are made from natural materials, non-mineral, that can be used as such as or after some modifications to achieve the behaviour and performance required. Two examples of these natural glues are casein and wheat flour-based glues that were used in the present study. Boards with different compositions were manufactured having as variables the type of glue, the dimension of the corn cob particles and the features of the pressing process.
The tests boards were characterized with physical and mechanical tests, such as thermal conductivity with a ISOMET 2104 and 60 mm diameter contact probe, density based on EN 1602:2013, surface hardness (SH) with a PCE Shore A durometer, surface resistance (SR) with a PROCEQ PT pendular sclerometer, bending behaviour based on EN 12089:2013, compression behaviour based on EN 826:2013 and resilience (R) based on EN 1094-1:2008, with a Zwick Rowell bending equipment with 2 kN and 50 kN load cells (Fig. 1), dynamic modulus of elasticity with a Zeus Resonance Meter equipment (Fif. 5) based on NP EN 14146:2006 and water vapour permeability based on EN 12086:2013.
The various boards produced were characterized according to the tests and the ones with the best results were C8_c8 (casein glue, grain size 2,38-4,76 mm, cold pressing for 8 hours), C8_c4 (casein glue, grain size 2.38-4.76 mm, cold pressing for 4 hours), F8_h05 (wheat flour glue, grain size 2.38-4.76 mm, hot pressing for 0,5 hours), FEV8_h0.5 (wheat flour, egg white and vinegar glue, grain size 2.38-4.76 mm, hot pressing for 0,5 hours) and FEVH68_c4 (wheat flour, egg white, vinegar and 6 g of sodium hydroxide glue, grain size 2.38-4-76 mm, cold pressing for 4 hours).2p.DE/NC
Assessment of water use efficiency in the household using cluster analysis
No full textConcerns over the efficiency of household water use have been increasing worldwide: water is intensively consumed with high inefficiencies. Detailed methodologies for the assessment of consumers’ behaviour that include the level of efficiency comparatively to their peers (i.e., similar socio-demographic characteristics) are needed to increase public awareness and to develop strategies related to the efficient use of water. This paper presents a methodology for evaluating the efficiency of indoor domestic water use based on peer comparison. Peer groups were established through cluster analyses according to their relevant socio-demographic characteristics. Finally, the most efficient consumers were identified and water efficiency levels were determined for individual households.820-827 pp.1877-7058 © 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the Scientific Committee of CCWI 2015 doi: 10.1016/j.proeng.2015.08.945Volume 119DHA/NESProcedia Engineerin
Laboratory study on the suffusion behaviour of coarse gap-graded soils for use as potential upstream crack-fillers in zoned dams
No full textThis paper presents an experimental study aiming at the evaluation the suffusion behaviour of coarse gap-graded soils, considered as potential upstream crack-fillers in zoned dams. Six granular gap-graded soils missing the medium-to-coarse sand fraction have been examined. Four soils have no fines, one has 5% of non-plastic fines, and one has 5% of clayey fines (with plasticity index of about 14%). The use of available methods to assess internal stability of soils suggests that the majority of the selected soils are highly susceptible to suffusion. Testing has been carried out in the Upward Flow (UF) seepage test. A cylindrical seepage cell is used to impose vertical flow, from the bottom to the top, along a soil specimen with 200 mm-diameter and 150 mm-thick. During an UF test, the hydraulic gradient in the soil specimen is slowly increased in steps. The observation of the erosion behaviour at the top surface of specimen, together with the evolution of the discharge flow rate, allows determining the hydraulic gradients causing initiation of erosion on top of the specimen and development of suffusion in the soil. A ‘sand boiling’ phenomenon has been observed in soils exhibiting suffusion, resulting in the deposition of the finer particles at the specimen surface. One may conclude that the lower the gradient associated to the onset of ‘sand boiling’ phenomenon, and the higher the amount of material deposited in the top of the specimen, the higher the likelihood of gap-graded soils to be effective acting as upstream crack-filler. Laboratory testing on soils with no fines clearly shows that the higher the content of the fine sand fraction the higher the amount of material deposited on top of the specimen, however, the higher the gradients associated to initiation of suffusion and development of 'sand boiling'. Whenever high hydraulic gradients are not likely to occur, the gap-graded soil with 5% of non-plastic fines should be more reliable at filling in cracks than the gap-graded soil with 5% of clayey fines.687-698ppDG/NGO
RealQual: Towards real-time high-resolution monitoring and prediction of water quality in estuaries and coastal areas - Final Report
No full textEste registo pertence ao Repositório Científico do LNECThis report presents the main activities and results of the project RealQual: Towards real-time highresolution
monitoring and prediction of water quality in estuaries and coastal areas, a collaborative project of the FLAD / NSF 2013, Portugal - U.S. Research Networks Program. RealQual aimed at developing the foundations of a quality-controlled network for real-time, high-resolution monitoring and prediction of the water quality in estuaries and coastal areas. Regarding the real-time monitoring component, an online monitoring station for water quality was maintained operational in the Tagus estuary. Several procedures were tested for data quality control using the data from the SATURN OHSU-CMOP (Oregon Health & Science University – Center for Coastal Margin Observation and Prediction) network and will be extrapolated to the monitoring network of the Tagus estuary. The numerical modelling system for water quality ECO-SELFE was extended to improve its flexibility. A preliminary application of the coupled hydrodynamics and biogeochemical model was performed in the Tagus estuary, based on the improvements made to the horizontal grid and bathymetry. Tests to the computational times showed that the use of the biogeochemical model in real-time is possible and a set of requirements were established towards this deployment within the Water Information and Forecasting System (WIFF). A dedicated operational Web-based platform was developed for the project, providing access to the real-time data and forecasts of the hydrodynamics and fecal contamination in the Tagus estuary.2520 - Arquivado na SE do DHADHA/NE
Critérios e metodologias para limitação de vibrações, em edifícios, provenientes de vias férreas
No full textA sustentabilidade das cidades, depende essencialmente do bom ambiente e da mobilidade dos seus habitantes. As vias férreas subterrâneas são hoje um meio de aumentar essa mobilidade. Nesta comunicação descrevem-se os critérios para a limitação (admissibilidade) dos níveis de vibração nos edifícios, e também do ruído, causados por vias ferroviárias subterrâneas, a metodologia para a sua previsão, e as metodologias para o seu isolamento, onde necessário.10pDED/NAIC
Reabilitação de fachadas. O isolamento acústico como factor contributivo.
No full textNo contexto da reabilitação da envolvente dos edifícios, nomeadamente em fachadas de edifícios habitacionais, é normalmente considerada a aplicação de sistemas de isolamento térmico pelo exterior (ETICS) e a substituição das janelas existentes por caixilharia de vidro duplo com menor permeabilidade ao ar. Estas opções centram-se fundamentalmente na verificação de exigências de natureza térmica e de redução de uso de energia, numa perspectiva de sustentabilidade ambiental. No entanto, e como critério de conforto integrado, a qualidade acústica da envolvente é também factor determinante [1]. Neste sentido, e tendo em conta os desideratos de sustentabilidade ambiental em causa, os quais assentam na promoção da utilização do transporte público, o ruído ambiental vs isolamento sonoro requerido, traduzível na consideração de espectros de ruído mais penalizantes em baixa frequência, cria a necessidade de avaliar essa influência. Assim, a presente comunicação dá conta dos resultados de estudo realizado sobre a conjugação dos aspectos referidos no isolamento sonoro das fachadas e consequentemente no conforto dos ocupantes.7pDED/NAIC
Ambiente acústico de/en la vivienda: al encuentro de una visión holística
No full textIn classical antiquity, the structure of knowledge was based on introspective philosophy,
medicine, mathematics and astrology, thus defining the sciences of life and of Human thinking.
However, over the years, due to the development of descriptive methods of analysis and of
thought itself, scientific knowledge began to be subdivided into specialized areas, creating
branches of knowledge that seemed to be different between them, but that make part of the
same philosophical and scientific view. And with acoustics it has not been different!
Derived from physics and embodied in technological solutions applied to propagation, reception
and interpretation of sound stimuli, the acoustics was divided into several branches, such as
electroacoustic, psychoacoustics, bioacoustics, environmental acoustics, building acoustics,
etc. In the case of the acoustic environment inside residential houses, there is no doubt about
the contribution of many branches of acoustics, for it. So, concerning a realistic assessment of
noise to which residents are exposed to, it must be taken into account all related aspects, a fact
that leads to the need for a more comprehensive analysis to be carried out in accordance with a
holistic view of the overall system.
At this conference, an overview about the acoustic ambient inside home will be presented,
emphasizing that the acoustics of the external environment and the acoustics of the building
unity are not two separated realities. In fact, they both contribute to that ambient in a closely
related form, namely in terms of generation, management, control, propagation and noise
perception. Understanding this relationship, both in higher education institutions, as in real
applications of noise control and management by policy makers and public administrations, it is
clear that both branches of acoustics referred to above have a cross-influence in the same
objective reality that is the protection of human against the adverse effects of noise.
In this context, it is proposed to give special focus on the need for a holistic analysis, integrated
and global, of exposure to noise, in order to have a harmonious development, both at individual
level and of the society as a whole.10pDED/NAIC
Assessing climate change impact in hospitality sector. Simplified approach using building resources consumption signature
No full textClimate impact assessments and the development of adaptation strategies requires the study of vulnerabilities and risk to climate variables. The energy and water consumption demand in hotel usually change with occupancy rate and climate. In this article a simplified methodology is presented and applied to identify the climate change impact in hospitality sector using the building energy and water signature. This methodology is applied to sixteen hotels (nine in Lisbon and seven in Algarve) with four and five stars rating. The results show that is expect an increase in water and electricity consumption (manly due to the increase in cooling) and a decrease in gas consumption (for heating). The hotels in Algarve are more vulnerable than Lisbon hotels.6pDED/NAIC
Monitorização de estruturas com interferometria SAR
No full textA monitorização de estruturas é uma atividade de grande importância para garantir a segurança de pessoas e bens. A geodesia tem um papel determinante nesta tarefa ao possibilitar a medição de deslocamentos em zonas de interesse com elevada precisão.
A interferometria por radar de abertura sintética (InSAR) permite obter deslocamentos numa rede de observação que contempla não só a estrutura, mas também a sua envolvente, de cuja estabilidade também depende. Esta tecnologia permite complementar as redes de observação já existentes ao aumentar o número de pontos observados e ao possibilitar a realização de observações com maior frequência.
O objetivo desta comunicação é apresentar alguns exemplos de medição de deslocamentos em estruturas realizados com a tecnologia InSAR e validar esses resultados através da comparação com deslocamentos obtidos por métodos geodésicos. Serão consideradas estruturas localizadas em Lisboa - o pavilhão MEO Arena e alguns edifícios na Baixa da cidade – e no Alentejo – uma barragem de aterro e a envolvente da sua albufeira. Os resultados obtidos mostram uma concordância elevada entre as duas técnicas, indicando que o InSAR pode ser uma mais-valia para ser utilizado em sistemas de alerta atempado na prevenção de situações de emergência.8pDBB/NG
Sistema integrado de monitorização da integridade estrutural e da durabilidade da Ponte da Ribeira D'Água na ilha da Boa Vista, em Cabo Verde
No full textApresenta-se o sistema integrado de monitorização da integridade estrutural e da durabilidade da nova Ponte da Ribeira D’Água na ilha da Boa Vista, instalado face ao caráter inovador de que se reveste a construção desta ponte em Cabo Verde e pela sua importância estratégica na ilha10p1DE/NOEConcepção, conservação e reabilitação de ponte