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How to communicate IAM in water losses and energy management – the experience of a collaborative project
No full textWater utilities have to deal with different challenges including ageing infrastructures, climate change and increased societal expectations. The ISO 50 000 and 55 000 standards are effective tools for implementing procedures by which organizations can work strategically on energy and infrastructure asset management systems, respectively. The implementation success of these management systems is determined by the reliability and availability of information and the capacity of water utilities to progress in the direction of sharing knowledge and skills, breaking down information silos and boundaries resulting from functional specialism. Collaboration is essential to achieve improvements in the long term. This paper aims to outline potential synergies between collaborative knowledge production and the implementation of structured approaches to increase water services sustainability. In the iPerdas2014 project, 17 Portuguese water utilities developed their own water losses and energy management plan following a joint training and capacitation approach. Results indicate that the use of a collective problem framing and a defined framework for decision making allows working strategically with water losses and energy efficiency issues, with a clear integration in the infrastructure asset management system. Straightforward communication since day one is critical to achieve top management support and staff involvement, establishing conditions for continuous improvement.8pComunicação apresentada na conferência LESAM 2015, IWA, Yokohama, Japan, 17-19 NovembroDHA/NE
Solos - Origem e conceitos
No full text38-39ppn.º 91DG/NGEAIndustria e Ambiente – Revista de Informação Técnica e Científic
Hazard potential classification of dams using a simplified methodology
No full textThe National Dam Safety Policy in Brazil (NDSP) assigns the classification of
dams to the regulating agencies, all dams having to be classified in terms of hazard potential.
The lack of appropriate basic data, such as topographic maps, makes it impossible to rely on
well-established methodologies and requires effort and creativeness to find appropriate
alternative approaches. This paper describes a simplified methodology implemented for
hazard classification purposes and compares its results with those produced by a standard
and more complete model (HEC-RAS) using the same basic data. Downstream valley
inundation area assessment is performed considering four dams of different sizes. The
results, although denoting some differences, evidence that the simplified methodology
produces credible results as far as the affected areas for potential hazard classification are
concerned. The simplified methodology was used to classify the whole portfolio of 121 dams
assigned to the National Water Agency (ANA) under the terms of the NDSP.01-10ppDHA/NR
Proceedia engineering
No full textThis paper presents a novel methodology for evaluating the efficiency of indoor domestic water use based on performance assessment functions that convert state variables (e.g. flow rate, volume) into performance indices ranging from 0 (the lowest performance) to 300 (excellent performance). Performance functions have been developed for the most common water use devices in the household. An overall household water use index was obtained from the individual water use device indices by weighting each device in accordance with the consumption structure of the household. The application of this methodology to 43 households allowed the quantification of potential water savings and the identification of device-specific measures to increase the water use efficiency813-819pp2015 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 2015DHA/NE
Ferramenta de apoio à gestão costeira e portuária: o sistema HIDRALERTA
No full textNesta comunicação, descreve-se o sistema HIDRALERTA (sistema de previsão e alerta de inundações em zonas costeiras e portuárias), sistema em ambiente SIG que tem como ideia-base a utilização de previsões da agitação marítima (a 180 horas) para calcular os seus efeitos na costa, nomeadamente em termos de galgamentos e inundações. Dos desenvolvimentos mais recentes ou em curso destacam-se: a construção de mapas de risco costeiro, a partir da análise de uma série de 30 anos de dados de agitação marítima; o desenvolvimento e aplicação do sistema de alerta e da plataforma WEB para a zona da praia de São João da Caparica e para o porto e baía da Praia da Vitória (Terceira, Açores); a aplicação, com recurso a ferramentas SIG, de metodologias quantitativas de análise das consequências do galgamento/inundação (por exemplo, o Processo de Análise Hierárquica – AHP); e a realização de ensaios em modelo físico de galgamento de uma secção do perfil do molhe sul do porto da Praia da Vitória, cujos dados serão utilizados na avaliação do desempenho de ferramentas baseadas em fórmulas empíricas, redes neuronais e/ou modelos numéricos. A comunicação termina com uma referência ao trabalho futuro.18pDHA/NP
Evolution of the hydrodynamics of the Tagus estuary (Portugal) in the 21st century
No full textThe ongoing rise in sea level affects tidal propagation and circulation in estuaries, and these changes can have far reaching
consequences on the sediment dynamics, water quality and extreme water levels. This study aims at anticipating the evolution
of the tidal dynamics in the Tagus (Portugal) in the 21st century, in particular due to sea level rise (SLR). The existence of a
resonance mode of about 8 hours in this estuary, that selectively amplifies both semi-diurnal and quarter-diurnal tidal constituents,
makes the response of the Tagus estuary to SLR unique. The study was conducted with a shallow water model, forced by
present and future conditions, namely higher mean sea levels and an extrapolated bathymetry based on present sedimentation
rates. Model results showed that SLR will significantly affect tidal asymmetry, in particular because the intertidal area can
decrease by up to 40% by the end of the 21st century. As a result, the strong ebb-dominance of this estuary will decrease significantly.
This evolution of tidal asymmetry will be counteracted by the effect of sedimentation of the salt-marsh areas. Also,
SLR will enhance the resonance in the Tagus estuary. As a consequence, extreme water levels will be higher than the sum of
present levels with the SLR.9-19pp15/1DHA/NECRevista Costeira de Gestão Integrada/Journal of Integrated Coastal Zone Managemen
Alkali-Aggregate Reaction, AAR – Dealing with AAR in large concrete structures
No full textA significant number of problems related to concrete deterioration have been detected in large concrete structures in Portugal and worldwide, the leading cause being AAR. The importance of these structures, the number of for which AAR has already been identified or is very likely to be diagnosed in a near future, as well as the number of structures that are under or planned for construction, which may also come to develop AAR is why it is still nowadays a major concern. Therefore, a study is being conducted at LNEC to diminish the negative impact of AAR by increasing knowledge on how to reliably control AAR in new structures and on how to properly assess its extent and potential for future development in the existing ones, so that the risks to structural integrity and need for mitigation/remediation actions can be properly assessed. This paper presents methodologies, based on state-of-the-art knowledge collected on that study, which may be used by the construction industry stakeholders in the prevention of AAR in new concrete structures and on AAR diagnosis and prognosis in existing concrete structures. The presented information also provides an insight to LNEC specifications that LNEC will soon publish on this thematic.10pDM/NBP
Obras de engenharia obrigadas a mitigar os impactes nos solos
No full text1pN.º 94DG/NGEAIndustria e Ambiente – Revista de Informação Técnica e Científic
Estudo sobre a hidrodinâmica e a morfodinâmica da Lagoa de Óbidos , Portugal
No full textEste registo pertence ao Repositório Científico do LNECNa lagoa de Óbidos, as ondas e as correntes de maré induzem rápidas alterações morfológicas levando ao fecho da sua embocadura. As dragagens são frequentes tendo o objetivo de manter a laguna aberta e proteger as construções marginais. No entanto, o efeito das dragagens no comportamento da embocadura é um tema pouco estudado, especialmente o impacto que poderá ter a adição de canais transversais aos tradicionais canais dragados.
No interior desta laguna as ondas induzem alterações significativas nas condições hidrodinâmicas. Através da aplicação de um modelo acoplado constituído por um modelo hidrodinâmico e um modelo de agitação marítima concluiu-se que as elevações da superfície livre dentro da lagoa aumentaram para uma direcção média da onda perpendicular à linha de costa. Foi também investigado o impacto que a interacção completa entre ondas e correntes tem na dinâmica sedimentar da lagoa de Óbidos, concluindo-se que o transporte de sedimentos para o interior aumenta em 30% durante a enchente se esta interacção for tida em conta no modelo numérico.
Os três planos de dragagens foram avaliados através da implementação de um modelo morfodinâmico. Os novos planos de dragagens aumentaram o prisma de maré e reduziram as diferenças de duração entre a vazante e a enchente devido aos canais principais norte e sul. Os canais transversais aumentaram o assoreamento no canal principal sul e promoveram a estabilidade do canal principal norte. No entanto, devido às baixas profundidades e a uma agitação marítima muito energética, as soluções de dragagens são incapazes estabilizar permanentemente a lagoa de ÓbidosDHA/NE
Thermal imaging of concrete dam surfaces to support the control of the evolution of pathologies
No full textThe pathologies of structures that cause changes of surface temperatures can be detected by the analysis of the temperature of walls and other surfaces. The measurement of the surface temperatures can be easily performed with the use of thermal imaging cameras which work like an ordinary digital camera and give, instantly, a colour image where the colours are related with the temperature of the surface. This paper presents a study of the use of this methodology in the monitoring of concrete dams, specifically on the detection of resurgences of water on the downstream face, usually related with the transfer of water.
Three concrete arch dams were used to test this methodology: Alto Ceira, Cabril and Alto Ceira II. On the day on which the images were taken (4th of June of 2013), Alto Ceira and Cabril were under normal operation. Both structures presented important cracks. These dams were used to test if, under normal conditions, namely with the thermal camera more than 100 m away from the dam, it was possible to detect colder areas. Alto Ceira II was, at that day, near the end of the construction. As it has several thermometers inside the concrete, the temperatures measured by these were used to validate the information on the thermal images.10pDBB/NGASecond International Dam World Conference Proceeding