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A 3D numerical wave tank for coastal engineering studies
No full textThis paper presents the validation of active and passive, made by a dissipation beach, numerical absorbing methods implemented in RANS-VOF FLUENT® code for modelling long time series of wave propagation interacting with coastal structures. Verification of both numerical techniques was performed in 2D – wave flume, and 3D – wave tank, this one using a multiple active absorption wave makers. The active absorption wave maker allows maintaining the incident wave generation and the mean water level along the time. Good results were obtained for 2D and 3D applications for active absorption wave maker at the generation boundary and both numerical beach and active absorption at the end of the flume/tank.1-10ppVolume 372DHA/NPEDefect and Diffusion Foru
Tratamento solo-aquífero como solução passiva para melhorar a qualidade de águas residuais tratadas antes da sua utilização para recarga de aquíferos
No full textEste artigo apresenta os resultados de um ensaio feito em escala de demonstração (DEMO) na Estação de Tratamento de Águas Residuais (ETAR) de S. Bartolomeu de Messines (SBM), onde foram construídos sistemas de tratamento em bacias (Soil-Aquifer Treatment, SAT, em nomenclatura anglo-saxónica). Os sistemas SAT visaram melhorar a qualidade do efluente tratado antes da sua descarga no ribeiro Meirinho, cujas águas posteriormente se infiltram no aquífero cársico Querença-Silves ao longo das secções influentes do ribeiro. A melhoria da qualidade da água foi conseguida utilizando a capacidade do solo para reduzir as concentrações de contaminantes, nomeadamente compostos farmacêuticos e nutrientes, através de processos naturais (e.g. a retenção de partículas, adsorção, absorção e biodegradação). Antecedendo este ensaio DEMO foram realizados ensaios laboratoriais em coluna-de-solo com o objetivo de testar as condições ideais de SAT utilizando diferentes misturas de solo como meio natural de depuração (Hernández e Gibert, 2015; Martins, 2016; Martins et al., 2016). As condições físico-químicas do solo foram optimizadas em termos de permeabilidade, teor em matéria orgânica e condições aeróbias / anaeróbicas. Os resultados obtidos mostraram uma melhoria da qualidade do efluente da ETAR após passar pelo sistema de SAT, para diversos produtos farmacêuticos e nutrientes.4pDHA/NR
Aplicação do questionário do modelo-de-três-níveis sobre políticas e governança ao caso de estudo Português do projeto BINGO
No full textThe BINGO project Work Package 5 envisages the understanding and improving of the decision making process at the individual, societal and institutional levels to cope with the expected impacts of climate change at six European research sites. The initial input of this work is based on interviews at each research site using the three-layer model questionnaire on water policy and governance from the Water Governance Centre – Content, Institutional and Relational layers. The purpose of this document is to describe the interviewing process, based on this questionnaire, of some members of the Portuguese community and of some relevant personalities, in order to provide the context of the Portuguese research site features and institutional framework. It aims at facilitating the BINGO partners understanding of the answers received and summarizing the main conclusions. For this purpose, the answers received are exhaustively analysed and the main issues regarding water resources management in Portugal are identified. The conclusions are presented according to the three-layer questionnaire on water resources governance and climate change risk management.
This report starts by presenting the framework of BINGO and, in particular, the objectives and activities regarding Work Package 5. It contains a brief reference to the three-layer model of policy and governance questionnaire, allowing a better understanding of its content. The findings and recommendations, to be discussed with the relevant stakeholders, are presented in chapter 3. The key conclusions are presented in the last chapter. Those will be the basis for the recommendations for improvement to be provided in the future by the BINGO project.Bingo project – Bringing INnovation to onGOing water management – a better future under climate change / CONFIDENCIALDHA/NR
Ventilação de edifícios de habitação: contributos para a eficiência energética
No full textAs preocupações ambientais de reduzir as emissões de gases de efeito de estufa como estratégia para mitigar o efeito das alterações climáticas tem impostos desafios à melhoria da eficiência energética do setor dos edifícios (Pinto, 2015). Na construção mais recente e na reabilitação de edifícios existe uma tendência para uma significativa melhoria da qualidade térmica da envolvente, nomeadamente para a melhoria do isolamento térmico de elementos opacos e dos vãos envidraçados (Fragoso, 2017). Estudos de mercado (SEEP, 2014) apontam a melhoria ou substituição das janelas como a medida de eficiência energética preferida pelos consumidores para melhorar o desempenho energético da habitação. Nas medidas de melhoria é inesperado os consumidores não identificarem a melhoria do sistema de ventilação, devido por exemplo à existência de correntes de ar através das frinchas das janelas ou, condensações superficiais em habitações. Por outro lado, em edifícios com elevado nível de isolamento térmico a ventilação pode ser responsável por mais de metade das perdas térmicas da fração na estação de aquecimento.22-25pp11.ª Edição - Maio de 2017DED/NAICIRevista Energui
Monitorização em tempo real no estuário do Tejo: Estação do Parque das Nações - Instalação e operação entre janeiro de 2016 e fevereiro de 2017
No full textThis report describes the design and installation of the Parque das Nações online monitoring station and the procedures relative to its maintenance and data verification undertaken between January 2016 and February 2017. This station is equipped with a SEBA MPS D3 multiparameter probe, which measures water levels, conductivity and water temperature, and a SEBA Slimcom2 data logger, for data acquisition and transmission. The data acquired during the period to which this report refers are also briefly presented. This monitoring station is under operation in the scope of the projects H2020 BINGO and FCT UBEST.2639 - Arquivado na SE do DHADHA/NE
Anomalies detection in adhesive wall tiling systems by infrared thermography
No full textAdherent tiling systems are widely used all over the world as wall cladding because of their aesthetic and
technical characteristics. However, anomalous behaviours often occur; compromising the overall behaviour
of facades, and possibly raising safety risks. The need to create expeditious, non-destructive and
accurate methods of inspection that can encourage these systems’ inspection and maintenance fomented
a research study on infrared thermography’s capacity of early detect anomalous zones in adhesive tiling
systems, such as detachments or presence of humidity, in controlled in situ conditions, proving it as a
valuable diagnostic tool.10pArtigo de Livre Acesso148DED/NRIConstruction & Building Material
Contributos para a caracterização da condição de fronteira do tipo rio em modelos numéricos de diferenças finitas
No full textA condição de fronteira Rio (“River”) dos modelos de diferenças finitas baseados no Modflow requer a
caracterização, nem sempre fácil, de um conjunto de parâmetros. Neste artigo apresentam-se sugestões para a
caracterização de alguns desses parâmetros com base em informação cartográfica e hidrogeológica.4pDHA/NR
Direct estimate of the breach hydrograph of an overtopped earth dam
No full textThe quantification of the breach hydrograph of an overtopped earth dam remains a challenge, even in controlled laboratory
conditions. In this work, the breach hydrograph is calculated as the product of the velocity normal to a breach cross section and the estimated
area of that cross section. Although theoretically simple, because it is based on the very definition of discharge, this direct approach is an
absolute novelty in dam-breach studies. To illustrate the application of the method, a laboratory model of an earth dam, built with cohesive
sediments, was closely monitored. Competent velocities were estimated from surface velocity maps measured with large-scale particle
image velocimetry (LSPIV). The breach area was estimated by analyzing images of the traces of a laser sheet on the free surface and
the breach bottom. The direct breach hydrograph was compared with an estimate based on the mass balance in the reservoir and with
the discharge obtained through a rating curve of a downstream spillway. The novel method was shown to reproduce the main expected
features of the breach hydrograph. The potential to provide estimates free from experimental artifacts caused by improper description
of inertial effects is underlined. The advantages and the difficulties inherent to the method are discussed.13pVolume 143 Issue 6DHA/NREJournal of Hydraulic Engineerin
The archive oh historical materials in digital era as cultural value
No full textDocumenting and preserving materials data is important both to fulfill researcher’s needs and to obtain social benefits concerning the related educational and historical value. The samples repository is also demanded as a basis for further understanding, innovation and development, besides the preservation of the materials historical value and information. The dissemination of those materials importance to non-specialized interested publics may also be enhanced by a database. DB-HERITAGE project (Database of building materials with historical and heritage interest) discusses in this paper the meaning of the archive as a cultural value that is established from the relationship between tangible (physical archive) and intangible (digital archive). Reflecting on the archive of historical materials as a heritage value, it is pointed out its significance for the valorization of the architectural heritage407-412ppAuthors would like to thank Fundação para a Ciência e Tecnologia – FCT for their support through PTDC/EPH-PAT/4684/2014 project: DB-Heritage – Heriage database on historical construction materials, and also National laboratory for Civil Engineering – LNEC for their support through the project DUR-HERITAGE – Durability and characterization of historical interest construction materials.DM/NM
Grading of portuguese maritime pine small-diameter roundwood
No full textThis paper presents work carried out with the aim of characterizing the mechanical behavior and developing visual and machine strength grading systems for Portuguese maritime pine roundwood for structural applications. Two samples of forty maritime pine logs each were collected, one in a northern region of Portugal and another in an interior central region. After drying, the logs were visually graded and
subjected to nondestructive tests, using vibration and ultrasounds, for determination of dynamic modulus of elasticity. The logs were then subjected to destructive tests for determining bending and compression strength and bending modulus of elasticity. These results were analyzed in order to identify the features to be considered in the strength grading process. From this analysis, a proposal was developed to
visually grade Portuguese maritime pine roundwood in two strength grades. According to the European strength class standard for solid timber, the upper grade has similar mechanical properties to the C50 class, whereas the lower grade is similar to the C35. The machine grading showed good potential as a result of the good correlation presented between the dynamic modulus of elasticity and the mechanical properties. However, the ultrasounds showed slightly better correlation than the vibration method, whereas the last one is more practical.vol. 29 ; n.2DE/NCEJournal of Materials in Civil Engineerin