Artigos de Revista

The modelling of chlorine residual in water supply systems is of great importance in managing disinfectant concentrations throughout the network. First order decay kinetics are currently often used to describe both bulk and wall chlorine consumption. However, more complex approaches have been proposed, namely a parallel, two-reactant second order decay model (2R model) that has been reported as yielding better accuracy for simulating chlorine bulk decay in laboratory tests. The recent EPANET Multi-Species Extension (EPANET MSX) brought enhanced capabilities for the simulation of chlorine residuals in water supply systems, including the use of the 2R model or any other formulation. In the current paper, the performance of the 2R model as well as of first and nth order decay kinetics was assessed for full scale modelling of chlorine in a transmission system. Results have shown that a similar level of accuracy can be achieved with the three tested kinetic models, provided that a good calibration of the wall decay coefficient is accomplished. Although with improved modelling capabilities, the use of the stand- alone EPANET MSX was less user-friendly than normal EPANET application by the lack of a graphical interface allowing for the visualization of chlorine concentration profiles along the system. The use of the 3D-enabled Epanet Java web application circumvented such limitations. This tool together with a better characterization and estimation of the bulk and wall decay components allow for a more practical and accurate modelling of chlorine in water supply systems, while taking advantage of EPANET MSX's enhanced capabilities.

Like othersimilarcoastalsystems,theAlbufeiralagoonisartificially openedeveryyeartopromotewaterrenewalandclosesnaturallywithinafewmonths.TheevolutionoftheAlbufeiraLagoonInletfromitsopening inApril2010toitsclosure8monthslaterisqualitativelyandquantitativelyanalyzedthroughacombination ofmonthly field surveysandtheapplicationofaprocess-basedmorphodynamicmodel.Field dataalonewouldnotcoverthewholespace

iGPI, the National Initiative for Infrastructure Asset Management is a Portuguese collaborative project led by LNEC(National Civil Engineering Laboratory, Portugal) through which 19 water utilities develop their own infrastructure assetmanagement (IAM) systems and plans in a joint training and capacitation programme. Technical assistance to theparticipating utilities is ensured by LNEC, IST (Technical University of Lisbon) and Addition, a software developmentcompany. The water utilities get collective as well as one-on-one support and specific training. They benefit fromnetworking with the other utilities in a common and simultaneous process, with similar difficulties and challenges, leading toan effective sharing of solutions. The developed products, including training materials, templates and guidelines fordeveloping strategic and tactical IAM plans, are available to the general public. This project has greatly contributed to theestablishment of reference methodologies and standards for IAM planning, in a range of utilities of widely diverse size andcontext, effectively defining an accepted best practice. This paper discusses the project

The new version of EN 459-1 standard for building limes redefined the classes of hydraulic limes and made the producers reformulate or reclassify their natural hydraulic limes. This work evaluates the mechanical, physical and microstructural behavior of mortars formulated with a recently produced natural hydraulic lime NHL3.5 that conforms to EN 459-1, submitted to natural marine environment, humid and standardized conditions, and also the benefits and drawbacks of adding metakaolin in partial replacement of lime. Mortars with NHL3.5 present positive results at young ages. The metakaolin addition increases strength while decreasing the capillary water coefficient. The behavior in an aggressive marine environment seems promising.

A organização e a caracterização de um espaço doméstico pode seguir determinados hábitos de funcionalidade doméstica, e aqui tanto há hábitos que decorreram da evolução da vivência doméstica ao longo de alguns milénios, como outros que, praticamente, acabaram de nascer, de certo modo,

Modelling of ventilation is strongly dependent on the physical characteristics of the building ofwhich precise evaluation is a complex and time consuming task. In the frame of a research project,two children day care centres (CDCC) have been selected in order to measure the envelope airpermeability, the flow rate of mechanical ventilation systems and indoor and outdoor temperature.The data obtained was used as input to the computer code CONTAM for ventilation simulations.The results obtained were compared with direct measurements of ventilation flow from shortterm measurements with CO2 tracer gas and medium term measurements with perfluorocarbontracer (PFT) gas decay method. After validation, in order to analyse the main parameters that affectventilation, the model was used to predict the ventilation rates for a wide range of conditions. Thepurpose of this assessment was to find the best practices to improve natural ventilation. A simpleanalytical method to predict the ventilation flow rate of rooms is also presented. The method isbased on the estimation of wind effect on the room through the evaluation of an average factor (2 (

At railway bridge approaches the track stiffness may vary rapidly and often differen-tial settlements take place between the stiff structure and the approach section of thetrack. These differential settlements lead to uneven track pro

Falar um pouco sobre o silêncio na arquitectura, considerando esta, naturalmente, como conjunto articulado de espaços interiores, exteriores e de transição, com presença doméstica e urbana e importantes ligações com o bem-estar que deve caraterizar os nossos cenários de vivência, será, talvez, falar de uma qualidade arquitectónica que acompanha e valoriza, seja, numa primeira linha, os respetivos atos de conceção desses espaços e ambientes e numa segunda linha, embebe e caracteriza as primeiras vivências diretas desses espaços logo que recém-concluídos, e atraentemente vazios e expetantes, produzindo-se, assim, imagens quase que estranha e eloquentemente silenciosas.

O enquadramento do silêncio como matéria da própria conceção arquitetónica básica e, em seguida, do mesmo silêncio como qualidade natural, ou da natureza, associada a múltiplos aspetos do conforto, e por sua vez matéria da referida conceção arquitetónica; e assim até parece que não nos conseguimos dele libertar; mas há ainda e naturalmente outras perspetivas a considerar no silêncio como quadro base de arquiteturas e pano de fundo do habitat humano, e nestas uma há cuja importância é basilar e que se refere ao silêncio como veículo de intimidade e de urbanidade.

Iremos falar, globalmente, dos compartimentos, cantos e recantos domésticos, dos espaços tendencialmente intimistas onde se processa a vida diária das famílias, um leque variado de espaços habitualmente com funções específicas, mas desejavelmente com uma equilibrada flexibilidade funcional, espaços privilegiados da apropriação familiar e individual.