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Wave Overtopping Analysis and Early Warning Forecast System
No full textStructures and zones of interest in coastal areas are exposed
to wave overtopping events. The consequences associated with those
events have a significant impact on human safety, the environment and
affected business areas. This paper presents the overtopping forecast,
warning and data analysis component of the HIDRALERTA system. The
goal of this system is to provide a platform for warning dissemination,
while managing the information generated by the risk forecast methodology.
Alongside the warning dissemination, the system is concerned with
the analysis of previous forecasts and it is designed to account for variability
between different zones of interest. Our discussion includes an
analysis on the variability expected by the system, a data model for
sensor and interpolation data, and the system’s user interface, which includes
a geo-referenced time-series data analysis tool. We present a case
study for Praia da Vit´oria port, Azores, Portugal.92267-282ppDHA/NPE201430 junho a 3 de julh
Real-time monitoring and forecasting system for early warning of recreational waters contamination
No full textA new WebGIS platform for urban drainage management was developed based on the integration of catchment-to-receiving waters modelling and on real-time on-line monitoring networks. The platform is devoted to the surveillance and real-time decision support for urban drainage management, especially for issuing early warnings for faecal contamination in receiving waters. The water information forecast framework (WIFF) platform was deployed in the Tagus estuary forced by the discharges from the Alcântara catchment, the largest catchment of Lisbon. The system combines the 3D hydrodynamics and water quality model ECO-SELFE, that simulates circulation and faecal contamination in the Tagus estuary, forced by the Alcântara urban drainage model, built in SWMM. On-line monitoring stations were installed in the Alcântara CSO and in the estuary. Several synoptic field surveys were conducted, aiming at improving the water quality models validation and integration and validating and complementing the on-line monitoring data. These campaigns also supported the search for relations between real-time measurable variables and faecal contamination indicators. Since microbial faecal contamination cannot be measured by existing sensors, ammonia and parameters measured by UVVis spectrophotometric probes are used as baseline parameters for continuous verification of the water quality forecasts.9 pDHA/NE
Avaliação de elementos estruturais de madeira: Desenvolvimentos recentes
No full textAlterações de uso, a ocorrência de deterioração ou o colapso parcial são situações que requerem a necessidade de avaliar a segurança ou funcionalidade de uma estrutura de madeira. No entanto, esta avaliação encontra as dificuldades associadas às características dos elementos estruturais de madeira (comportamento anisotrópico, elevada variabilidade
das propriedades físico-mecânicas e higroscopicidade com efeito pronunciado nas
propriedades físico-mecânicas) e do efeito do nível de conservação (deterioração) na
redução das propriedades mecânicas. Estas dificuldades são reconhecidas internacionalmente e têm vindo a ser debatidas no âmbito de diversas comissões científicas e técnicas nos últimos 5 anos. A presente comunicação pretende dar a conhecer a atividade desenvolvida por estas comissões e enumerar algumas das novas metodologias de
avaliação de estruturas de madeira.Os autores agradecem à Ação COST FP1101 Assessment, reinforcement and monitoring of
timber structures a oportunidade de debater temas relativos à avaliação da segurança
estrutural de estruturas de madeira.8114ppDE/NEM201426 a 28 de novembr
A 3D discrete particle model for rock fracture: micromechanical parameters calibration
No full textOs modelos detalhados de partículas, MP, ao terem em consideração a estrutura granular da rocha incluem de forma explícita a aleatoriedade do material e introduzem um tamanho limite à localização do dano. Neste trabalho é apresentado um modelo de partículas rígidas esféricas que tem sido desenvolvido tendo em vista o estudo da fratura em betão e em rocha. A interação entre partículas é definida com base na estrutura de Voronois dos centros de gravidade das partículas esféricas. Adota-se um modelo de contacto múltiplo, no qual a área da superfície de contacto é dada pela área da faceta comum dos Voronois associados a cada partícula. Vários estudos paramétricos são apresentados de modo a demonstrar a influência dos parâmetros micromecânicos, elásticos e resistentes, na resposta macroscópica dos sistemas de partículas.14ppDBB/NMM
Buckling load of multi-step non-uniform steel towers
No full textO presente trabalho propõe duas soluções analíticas diferentes para o cálculo da carga crítica elástica de torres de telecomunicações em aço, constituídas por troços rectos de secção circular oca com diâmetros diferentes, e sujeitas a uma carga axial concentrada no seu topo. Estas soluções foram obtidas por um método energético, com base em diferentes configurações da deformada transversal da torre. A comparação entre os seus resultados e os obtidos por via numérica mostram que estas soluções analíticas oferecem uma boa alternativa para o cálculo da carga crítica, sobretudo no caso da segunda solução, que fornece muito bons resultados para uma gama geométrica de torres mais alargada, com variações importantes de inércia.71-88ppVol. 3 - Nº 1DE/NCERevista da Estrutura de Aç
Definição de aplicações tecnológicas baseadas em dados de telemedição para promover a eficiência no consumo de água-energia em sistemas de abastecimento
No full textOs sistemas urbanos de abastecimento de água têm beneficiado de uma forte evolução tecnológica nas últimas décadas, traduzindo-se na melhoria global dos serviços prestados. As tecnologias de informação têm contribuído para esta melhoria, através da leitura remota, comunicação e registo continuo de parâmetros como o consumo de água e a pressão. Embora muitas entidades gestoras utilizem já estas tecnologias, o foco principal tem sido a monitorização da rede e dos grandes consumidores parav controlo de perdas de água nos sistemas. Além disso, a maioria das tecnologias de telemedição são muitas vezes utilizadas de forma isolada sem integração entre elas e com outros sistemas de informação. Portanto, há necessidade de uma abordagem mais completa, que contemple aplicações não tradicionais e que benefecie da análise cruzada entre dados obtidos, com elevada frequência, por telemedição de medidores de caudal instalados para monitorização das redes e de contadores instalados nos consumidores. Neste artigo apresenta-se o trabalho desenvolvido no âmbito do projeto europeu iWIDGET no sentido de identificar, validar e testar um conjunto de aplicações inovadoras baseadas em dados de telemedição adquiridos em tempo real e que permitem melhorar a eficiência no consumo de água e de energia associado em sistemas de abastecimento.9 ppActas do 12º Congresso da Água/16º Encontro de Engenharia Sanitária e Ambiental/16º Simpósio Luso-Brasileiro de Engenharia Sanitária e Ambiental. Lisboa, 5-8 de Março 2014DHA/NE
Identification of alkali-reactive aggregates: some examples
No full textAlkali–aggregate reactions have been known for decades although the acceptance of their occurrence has been delayed
in some countries until the 1990s. Potential reactivity has been identified in most of the rock types used as aggregates
around the world. The most common reactive rocks are sedimentary (e.g. opaline sandstone) and metamorphic (e.g.
gneiss). However, igneous rocks such as granites have also proved to be reactive in some areas and innocuous in many
other regions. It has been concluded that the designation is not enough to label a rock as reactive and that microstructure
is very often the determinant factor of reactivity. In the present study a summary ismade on the state-of-the-art on alkali–
aggregate reactions. Emphasis is given on the identification of potentially reactive aggregates based on petrographic
methods. Examples from a large number of samples analysed in the scope of a research project are presented.The authors would like to acknowledge Centro de Geologia
(University of Porto), Fundac¸a˜o para a Cieˆncia e Tecnologia
for the financial support of the Project IMPROVE (Ref:
PTDC/ECM/115486/2009), and Azorean Regional Government
for financial support of Project ReAVA. The SEM-EDX
data were obtained at the Materials Centre of the University of
Porto (CEMUP) whose equipment was funded by the projects
REEQ/1062/CTM/2005 and REDE/1512/RME/2005 of FCT.3110pDM/NMMProceedings of the ICE - Construction Material
A multidisciplinary approach to the study of archaeological mortars from the town of Ammaia in the roman province of Lusitania (Portugal)*
No full textThe Roman town of Ammaia (in Marvão Region) is considered one of the most important
recent findings of the Roman presence in Portuguese territory. It was settled in Republican
times and abandoned in the seventh century. In this research, 17 masonry mortars and renders
from the West Tower (South Gate), the residential area near the West Tower, the macellum, the
peristylium, the public bath building, the podium of the temple and the portico of the forum
were analysed. The methodology of chemical, mineralogical and microstructural characterization
has involved several complementary techniques, including stereomicroscopy, X-ray
diffraction, thermal analysis and scanning electron microscopy coupled with energydispersive
X-ray spectroscopy. The results indicate that the mortars from the beginning of the
town’s edification were mainly composed of soil (clays). Later, during the main Roman
building period, mortars were composed using a calcitic binder and the mortar composition
varied according to their use and function. The samples from a period subsequent to the
Roman occupation are based on a dolomitic binder. From the present study, relevant information
has been acquired about the technological evolution of Roman construction in
Ammaia, the historical context of the archaeological structures and guidelines for the
conservation and restoration of mortars.The authors wish to acknowledge the Fundação para a Ciência e Tecnologia for financial support
(Ammaia Project—PTDC/HIS-ARQ/103227/2008 and GODESS Project—PTDC/HIS-ARQ/
108758/2008). The authors also wish to thank Sara Valadas, Luís Dias and Nuno Carriço
(HERCULES Laboratory, University of Évora), Sandra Velez (Geosciences Department, University
of Évora) and Joaquim Carvalho, Dulce Osório, Valentina Castro (CIDEHUS, University
of Évora).741–24ppVolume 56, Issue 1DM/NMMArchaeometr
Modulação de cenários de rotura em barragens de gravidade de betão com um modelo discreto de partículas
No full textA análise de cenários de rotura em barragens de gravidade em betão requer ferramentas computacionais que sejam capazes de lidar com o fenómeno da fendilhação. Neste trabalho adota-se um modelo detalhado de partículas (MP) nas zonas em que se espera que esta ocorra. É proposto um modelo MP híbrido, no qual, a rigidez de cada elemento finito onde se prevê que ocorra um comportamento não linear é substituída pela rigidez do sistema de partículas adotado na discretização do seu interior. Por razões computacionais, o tamanho adotado para as partículas é superior ao tamanho máximo do agregado incorporado no betão de barragens. Os resultados obtidos, estáticos e dinâmicos, com o modelo MP proposto são comparados com os resultados obtidos com um modelo de dano de duas variáveis e com um modelo MP global.16ppSeminário / 5as Jornadas Portuguesas de Engenharia de EstruturasDBB/NMM
Equity in Public Transport: An intractable policy problem or a set of methodological challenges?
No full textEquity inclusion in transport policy and planning remains a complex and, often, it is considered an intractable problem. Indeed, addressing equity in transport decision making will require a multi-dimensional perspective in a dynamic socio-technical and political environments, where territorial and time variables play a role.
Although all transport actions (programs, plans and projects) have equity impacts, the ex ante equity assessment of transport investments is rarely done in practice. As such, the distribution of transport impacts (benefits and costs) is often perceived as unfair across the population/territory (vertical and spatial equity issues), specially when transport investments exclude several groups (non-drivers, people with disabilities, lower-income, non-motorized users such as cyclists and pedestrians, etc.). On the other hand, policy makers claim for horizontal equity in public policies and, therefore, road transport users shall pay for the costs of infrastructures’ provision/use (this includes external costs such as congestion and pollution). Therefore, transport planning problems involve the consideration of multi-faceted equity objectives.
This paper aims to contribute to embed equity into future transport policies and investments. The research is anchored in the following preposition - any future guidance to include equity in transport decision-making will depend on the possibility of innovation and cross-fertilization of theory and practice across multiple disciplines and policy sectors. The method comprises the following inter-related steps:
a) Integration of methodological insights to transport equity analysis through integration of other theories and practices that resulted from a comprehensive review of key research policy streams such as: i) socio-technical transition and innovation decision making and ii) health policies. The former is considered due to the importance of integrated transport governance models and the dynamics of change (co-evolution of institutions and infrastructures, technology and society and inter-linkages) as the appropriate foundation for equity, whereas the health care industry provides a rich database for addressing both equity issues and quality of access (to health services).
b) Assessment of key challenges to policy and equity evaluation that result from the consideration of step a) in setting a fare policy. This will be demonstrated through a case study developed for Haifa metropolitan area which evaluated equity impacts of bus public transport fare changes.
To the best of our knowledge, this research is novel in being the first attempt to integrate the above streams for advancing the equity problem in transport. The literature review on transport policy and equity evaluation reveals that there is no agreed upon methodological framework to account for and to measure equity in transport. Since no harmonized conceptual framework exists yet in Europe, further developments are requirement before equity considerations can be fully incorporated into the decision making process. As such, expected results from this multidisciplinary fertilization will contribute to outline an improved roadmap for equity evaluation in transport.A missão a Santander para apresentação do artigo foi financiada pelo European Cooperation in Science and Technology, através da ação COST TU1209 Transport Equity Analysis: assessment and integration of equity criteria in transportation planning.1316The data collection and research work for this paper was co-funded through a COST Short Term Scientific Mission of the former author to Technion-Israel Institute of Technology within COST TU1209 Transport Equity Analysis: assessment and integration of equity criteria in transport planning.DT/NPT