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Implementing tactical plans to improve water-energy loss management
No full textWater utilities are aware of the water-energy loss relevance in supply systems. However, they still mainly focus on daily water loss control (real and apparent losses), without considering the impact on embedded energy. Moreover, they are mostly concerned with the economic dimension and, in most cases, tend to disregard the impact that water-energy loss may have on the quality of service, communication with the customers, social awareness, water quality and environment. This paper focuses on the application of the AWARE-P IAM methodology to improve water-energy loss management in water supply systems while demonstrating the main benefits from implementing an integrated approach for water losses and related energy assessment. Results show that indeed the participating iPerdas utilities were able to define tactical measures prone to a more efficient and sustainable service.8 pPublição apresentada no congresso LESAM 2015, IWA, Yokohama, Japan, 17-19 NovembroDHA/NE
The effectiveness of laboratory expansion tests in the identification of slowly reactive aggregates
No full textCases of alkali-silica reaction were reported for the first time in Portugal in the 1990s, mainly associated with slowly reactive aggregates of granitic composition used in large dams. A research project was developed aiming at the determination of the most effective laboratory test for the identification of the alkali reactivity of this type of aggregates. The laboratory tests followed the recommendations and standards developed under the scope of RILEM Committee on Alkali-Silica Reaction, namely the petrographic method and the concrete prism tests at 38°C (RILEM AAR-3) and 60°C (RILEM AAR-4.1). Also accelerated mortar bar tests were performed according with ASTM C1260 standard.
The results obtained in the last 4 years for about 40 granitic samples show that although the petrographic method can be very useful for the identification and quantification of potentially reactive forms of silica, it is mandatory to evaluate the variability of granularity of the rocks at the quarries’ scale and the possible presence of faults or dykes with which the occurrence of microcrystalline quartz might be associated. It could be confirmed that the ASTM C1260 (80°C, immersion in 1M NaOH solution) accelerated mortar bar test, with its generally accepted limits, is ineffective for granitic aggregates. A suggestion is given for the revision of the threshold and/or the duration of the test. The concrete prism test AAR-4.1 (60°C, relative humidity>95%) proved to be more effective to identify a larger number of slowly reactive granitic aggregates than the AAR-3 (38°C, relative humidity>95%). The results are discussed in relation to two different criteria proposed by other authors.72-80pp.The authors wish to acknowledge the Foundation for Science and Technology (FCT), under project IMPROVE PTDC/ECM/115486/2009, and LNEC for the financial support. The authors affiliated in the Center of Geology of University of Porto are thankful to FCT for the funding in the scope of the Strategic Project PEST-OE/CTE/UI0039/2014.Vol 41 No 2DM/NMMConcrete in Australi
Boosting innovation in the water sector - The role and lessons learned from collaborative projects
No full textA key worldwide challenge in most sectors is to boost the effective adoption of innovation, as underpinned by the new European Union research programme Horizon 2020, which focuses on increasing innovation in Europe from 2014 to 2020. This is particularly relevant in the water sector, often perceived as conservative and averse to change. This paper discusses the role that collaborative knowledge-transfer projects can play in effectively rolling out R&D in the water industry. LNEC (Laboratório Nacional de Engenharia Civil) has designed a structured model based on a phased programme and a network of utilities and researchers. The paper presents the core principles, the rationale, the model and methods used, and the theoretical background, as well as the project’s impact, outcomes and products. The discussion highlights the lessons learnt and provides a formal analysis of the advantages of focusing on middle management as an effective entry point, even if innovation is needed across the organization. Making training materials, guidelines, use cases, data and software publicly available after the project’s end has proven to have a decisive multiplying effect. The paper also argues in favour of the collaborative model as a basis for R&D sustainability, and details on-going and planned developments.1516–1523ppIWA Publishing 2014 DOI:10.2166/wst.2015.362DHA/NESWater Science & Technology, 72.9|201
Risco de inundação em estuários. Caracterização das componentes de perigo a diferentes escalas espaciais.
No full textNos estuários ou outros sistemas de transição, como lagunas e rias, a previsão das zonas inundáveis deve
ter em consideração que o processo de inundação resulta da conjugação de vários fatores, associados a
condições climatéricas particulares, como a coincidência de níveis de maré elevados com caudais fluviais
intensos, ou com sobrelevações de origem meteorológica. Nas zonas urbanas adjacentes, acresce o efeito
dos níveis elevados na capacidade de resposta dos sistemas de drenagem, principalmente durante
episódios de precipitação muito intensa e concentrada no tempo. Assim, a análise do risco de inundação
em estuários deve considerar as diferentes componentes de perigo de forma integrada (EU/EXIMAP,
2007) e basear-se em metodologias de previsão robustas e validadas. O presente estudo teve como
objetivo a caraterização do processo de inundação no estuário do rio Tejo, incluindo a identificação das
componentes de perigo, a duas escalas espaciais distintas (escala regional e escala local).17-18ppDHA/NE
Quality assessment of GNSS with short-length session in the displacement measurement of a large embankment dam
No full textAfter a large set of GNSS tests carried out on a 325 m baseline, with different length observation sessions, we assessed the quality of GNSS with short-length sessions to monitoring the displacements of a large embankment dam, in south of Portugal. The GNSS campaigns were performed at the same time of classic geodetic observation campaigns, with Leica TCA2003 tacheometer and Leica NA2 optical level, and the results were compared: the standard deviations of the differences of the two methods for horizontal and vertical displacements were 3.6 mm and 5.7mm, respectively. These values are in agreement with those which we obtained on a 325 m baseline with GNSS using sessions of 5 minutes length. The results of this test show that the GNSS with short-length sessions has enough precision to monitoring large embankment dams.10pDBB/NG
In-situ survey of the presence of soluble salts associated with decaying azulejos
No full textPattern or figurative azulejos are commonly found decorating the interior of churches, palaces and religious buildings in Portugal, representing local productions from the late 16th century onwards. The history and micro-climatic background of each building determined that not every azulejo reached the present day in good condition.
Restorers tend to associate azulejo decay to the action of soluble salts through cycles of dissolution and crystallization. NaCl is often mentioned and the suspicion of its presence justifies long desalinization processes during restorations.
Whenever there are glaze lacunas and the ceramic biscuit is exposed, efflorescence is sometimes apparent at the surface. Other times there is no visible efflorescence, even in locations inaccessible to cleaning actions, and no signs of sanding associated to crypto-florescence.
The aim of this research was the survey of in situ forms of degradation, and the sampling of efflorescence and decaying biscuits, aimed at: i) determining the occurrence of soluble salts even if unapparent; ii) determining analytically their nature; iii) establishing circumstantial relations between the occurrence of particular soluble salts and decay, to be later explored through laboratorial simulations.
29 properties throughout Portugal were visited (of which 14 inland and 15 in coastal areas) in which walls were lined with azulejos produced in Coimbra or Lisbon.
The salt samples and small fragments collected in situ were analysed with a HITACHI 3700N Scanning Electron Microscope with microanalysis unit (SEM-EDS) at the Hercules Laboratory (Évora University).
The communication will illustrate the results of the study, connecting some forms of decay to the action of soluble salts recurrently found associated with them such as NaCl, more abundantly found in near-shore properties, along with sodium carbonate (trona). Magnesium and calcium sulphate were more common in inland properties.Investigação realizada ao abrigo de um projecto de doutoramento IIFA/UEVORA. Doutoramento financiado pela FCT ao abrigo do protocolo IMC-PROP/5170/2011.255-258pp.Investigação realizada ao abrigo de um projecto de doutoramento IIFA/UEVORA. Doutoramento financiado pela FCT ao abrigo do protocolo IMC-PROP/5170/2011.
Participação do Laboratório Nacional de Engenharia Civil realizada ao abrigo do Projeto 0202/111/19014 (IPERION-CH.pt).DM/NBPCProceedings of the International Conference Glazed Ceramics in Architectural Heritage (GlazeArch 2015
Proposal for the dam safety regulation of Mozambique
No full textThe paper presents the mains aspects of the proposal for the Dam Safety Regulation of Mozambique (DSRM), emphasizing aspects that may be considered innovative or specific to the Mozambican dam panorama. The scope of the DSRM and the criteria for dam vulnerability and potential damage in the downstream valley classification are presented. The Mozambican institutions that will be involved are listedand their roles briefly presented. Concerning the dam safety control, the Mozambican data base purposes are described and the several procedures and documents that will be used for that control are briefly listed and discussed . The main safety requirements to be considered in the design stage that were included in the proposal are also included.
Finally, the guidelines adopted for the defaults penalties and for the owners financial support obligations are briefly described.CD/C
Development of a metering methodology
No full textThis paper incorporates an extended definition of sustainable development of urban water cycle services combined with a system to measure the progress towards sustainability. Two dimensions of sustainability, namely the values of assets and the practice of governance are added to the three conventional dimensions, social, economic and environmental impact. The metering system further comprises objectives, criteria and metrics. The method implies a definition of risk factors that may compromise a sustainable development and the impact of interventions to compensate this. The concept of metabolism or other LCA methods may be used to analyze the impact of these interventions on the environment as well as the social and economic impact and the effect on the assets and governance. The impact of climate change is considered to become a main aspect in future urban water cycle services and is addressed in particular.8 pComunicação apresentada na conferência LESAM 2015, IWA, Yokohama, Japan, 17-19 NovembroDHA/NE
On the use of under sleeper pads in transition zones at railway underpasses: experimental field testing
No full textThe railway track at transition zones to bridges or to other structures usually requires considerably more interventions to
maintain the same open track service quality and safety levels. Under sleeper pads (USP) have been reported to contribute to
reduce degradation and frequency of maintenance operations in open ballasted tracks, and recent numerical studies have
suggested its use in transition zones. In this study, the influence of using USP at transition zones to underpasses was
investigated. The structural behaviour of two transitions to similar box culverts was compared. USP were added to the
sleepers in one of the transitions. Track characterisation using non-destructive tests is presented and analysed.
Measurements of track response from passing trains are also presented and discussed. Results indicate that USP influence
the dynamic behaviour of the track, increasing its vertical flexibility and amplifying both rail displacements and sleeper
accelerations.112-128pp.11(2)DT/NITStructure and Infrastructure Engineerin
Geopolymers in cultural heritage: their application in azulejo conservation
No full textCurrently, the restoration materials used to fill gaps in architectural historic azulejos (e.g. lime or organic resin pastes) present relevant drawbacks in terms of compatibility, efficacy or durability. The current solutions are not able to fully protect the azulejos resulting in further deterioration. Geopolymers can be a potential solution for azulejo lacunae infill given the chemical-mineralogical similitude, durability and versatile range of physical properties that may be obtained through the manipulation of their formulation and curing conditions. This communication presents and discusses the viability of the use of geopolymeric pastes to fill lacunae in azulejos or to act as “cold” cast ceramic tile surrogates reproducing missing azulejo fragments. The formulation of geopolymers (type and concentration of activators, aluminosilicate source and water content) and curing conditions was optimized. The need for post-curing treatments (desalination) was also taken into consideration in view of the purpose of their application: the restoration of outdoor architectural historic azulejos, which are exposed to adverse environmental conditions. The possible advantages and disadvantages of the use of geopolymers in the conservation of azulejos is also discussed.279-282pp.Project CerAzul: Research and development of materials and methods for the conservation of historic azulejos (PTDC/CTM-CER/119085/2010). LNEC own financing under Proc. 0202/111719014 (RI. IPERION-CH.pt).DM/NBPCProceedings of the International Conference Glazed Ceramics in Architectural Heritage (GlazeArch 2015