Artigos de Revista

Este trabalho visa apresentar um sistema de avalia‡Æo de desempenho inovador para diagn¢stico e apoio na tomada de decisÆo sobre medidas de eficiˆncia energ‚tica em servi‡os urbanos de  guas. O sistema avalia o desempenho em termos de eficiˆncia e efic cia a quatro n¡veis f¡sicos de an lise: sistema, etapa, subsistema/componente de infraestrutura e equipamento/processo de tratamento. Demonstra-se tamb‚m a sua aplica‡Æo numa entidade gestora (EG) para identifica‡Æo expedita das etapas priorit rias onde aprofundar o diagn¢stico e intervir. Os resultados mostram que abordagens como esta, que nÆo atendem apenas … eficiˆncia dos equipamentos e permitem a avalia‡Æo integrada nos servi‡os urbanos, sÆo fundamentais no apoio … tomada de decisÆo a um n¡vel t tico, e facilitam o alinhamento e execu‡Æo dos planos estrat‚gicos e operacionais.

A detailed modelling approach to represent masonry at the meso-scale is proposed, basedon the discrete element method, considering the nonlinear behavior of the joints and the units. Thefracture of units is represented by the bonded-block concept, in which a random network of potentialcracks is created, allowing the progressive development of failure mechanisms. For simplicity, onlythe 2D case is presented, but the extension to 3D is straightforward. A key component of the proposedmodel is a framework for a joint or interface constitutive model, including the post-peak softeningrange, taking into account the experimental fracture energies. In this model, the softening curves intension or shear are defined by piecewise linear segments, calibrated to reproduce the most commonmasonry constitutive models. The essential issues involved in the application of bonded-blockmodels to masonry are examined, namely the block shape, either Voronoi polygons or triangles; size;deformability; and the influence of the main constitutive parameters. Uniaxial compression tests areanalyzed in detail. The simulation of a well-known experiment of a brick panel under shear showsthe good performance of the proposed approach. The investigation results demonstrate the model

Este artigo é globalmente dedicado à temática de uma habitação especialmente adequada para idosos e pessoas fragilizadas, em termos ergonómicos e funcionais, mas sem quaisquer tipos de estigmas associados ao idadismo, e, portanto, integrada numa solução residencial e urbana intergeracional, participativa e bem relacionada em termos sociais, urbanos e arquitetónicos. Em termos específicos no presente artigo aborda-se, em primeiro lugar a matéria associada a uma habitação que possa constituir um lugar positivo para o corpo, para a mente e para o espírito ; sequencialmente desenvolve-se uma reflexão sobre a caracterização doméstica considerada essencial para o futuro da habitação e finalmente tratam-se as vantagens de uma domesticidade envolvente

A durabilidade das estruturas de betão armado reforçadas com polímeros reforçados com fibras de carbono (CFRP) tem vindo a ser estudada essencialmente através de protocolos de envelhecimento acelerado em laboratório, existindo poucos estudos de envelhecimento natural (real).Este trabalho pretende contribuir para o conhecimento da durabilidade da ligação entre betão e laminados de CFRP, aplicados segundo as técnicas EBR e NSM, utilizando um adesivo epoxídico.Foi implementado um programa experimental, que incluía um ambiente de referência (20 °C / 55% HR) e quatro condições de exposição natural, induzindo principalmente (i) carbonatação, (ii) ciclos gelo-degelo, (iii) temperaturas extremas, e (iv) ação de cloretos. Foi ainda estudado o efeito da imersão contínua em águaa 20 °C.A durabilidade da ligação foi avaliada até 2 anos de exposição, através de ensaios de arranque direto. Constatou-se que o desempenho da ligação nos envelhecimentos naturais apresentou níveis relativamente reduzidos de degradação para ambas as técnicas de reforço.

This investigation addresses the durability of the adhesive bond between near-surface-mounted (NSM) carbon fiber-reinforced polymer (CFRP) strips and concrete, under real-time field conditioning and laboratory-accelerated conditioning. Four natural outdoor environments were considered in the experimental program to induce aging mainly by carbonation, freeze-thaw cycles, elevated temperatures, and airborne chlorides from seawater. Additionally, a control environment (20°C and 55% RH) and a water immersion environment under controlled temperature (20°C) were considered. The durability was studied mainly throughout the mechanical properties obtained from (1) the involved materials (concrete, epoxy adhesive, and CFRP strips); and (2) the bond specimens, with a period of exposure up to 2 years. The bond performance of NSM-CFRP strips to concrete was slightly affected by environments under investigation, being water immersion and freeze

In this paper, capillary stresses and water retention of regular arrangements of rough spherical particlesare analysed to shed light on the effective stress in unsaturated soils. These arrangements can be usedto model soils with uniformly graded round particles such as sand as they are simpler to analyse due totheir symmetries. Capillary stress determines the effective stress in unsaturated sphere arrangementsand is highly dependent on the morphology of the soil voids. In general, it is shown that capillary stress and water retention dependence on suction and degree of saturation in regular arrangements of spheres is more complex than usually assumed with relevant implications for unsaturated soil mechanics and its effective stress. It is also shown that: (i) sphere roughness explains the observed disappearance of capillary stresses in sand with drying; (ii) the capillary stress evolution with suction (or RH) is non monotonic; (iii) it is possible to have significant capillary stresses at zero suction in regular and irregular sphere arrangements, and the Bishop

This work aims to determine the exploitable wave energy resource at five potential sites close to harbour pro tection facilities at the Portuguese coast, namely at the Azores archipelago, at Madeira Island and at Sines, on the coast of mainland Portugal. For that purpose, a third-generation wave model SWAN is used to transfer the offshore estimates of sea wave conditions to those points over the last 40 years. Sea states and wind fields are provided by the climate reanalysis datasets ERA5

Foram testados novos carbonos ativados em pó (PACs) de pinhas e casca de pinhões (PNSs) para a adsorção competitiva de compostos farmacêuticos (PhCs) suplementados (100 µg/L) em efluentes secundários e licor misto de uma estação de tratamento de águas residuais urbanas. O PNS77 ativado com vapor de água, com estrutura hierárquica de poros e 1463 m2/g de área BET, superou a referência comercial (WP220, origem mineral) para PhCs e controlo de matéria orgânica dissolvida (DOM). A modelação dos dados de isotérmica de adsorção para a gama ng/L revelou que 80% da remoção de carbamazepina e diclofenac seria alcançada dosando 8-15 mg/L PNS77 a efluente secundário, enquanto que para o licor misto a dose deve ser duplicada para balançar o aumento da competição.

Recently, water utilities have been making considerable investments in sewers' monitoring; however, in most cases, assuring data reliability is yet a challenge. Often, hydraulic data is collected in sewers overlooking best practice aspects. Assuming confidence in data, while disregarding cautions verifications, might lead to inadequate uses of data. The paper presents a methodology aiming to narrow the gap between science and industry, regarding monitoring programs in urban drainage. A procedure to enhance hydraulic data reliability, in line with ISO/IEC 17025:2017, was developed, applied and validated, enabling a final evaluation on data and site adequacy and an overall identification of improvement opportunities. The availability of a valuable case study comprising 32 flowmeters from Portuguese utilities, in eastern Europe, presented an opportunity to create a story line, test the procedure's coherence, present it to the technical community and evaluate the constraints that utilities, in their everyday working context, are faced with. The procedure is presented in detail and a collection of examples of its application is shown. In the final evaluation, most monitoring stations' alignment with best practice requirements were either high (25%) or acceptable (44%), regarding their overall performance and compliance with both data and site adequacy. For all of them, improvement opportunities were identified.