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This paper presents and demonstrates a novel scenario-building methodology that integrates contextual and future time uncertainty into the performance assessment of water distribution networks (WDNs). A three-step approach is proposed: (i) System context analysis, identifying the main key factors that impact the WDN performance; (ii) Scenario definition, identifying the implicated WDN variables, describing its possible evolution, and conjugating them to further establish the reference scenari...
This study proposes a methodology for developing deterioration models and predicting the service lives of vertical assets of urban water systems (i.e., water storage tanks and pumping stations) using regression analysis. The main factors contributing to the deterioration of these assets are analyzed. Simple and multiple linear regression models of average and maximum deterioration are calculated for 22 water storage tanks and 17 wastewater pumping stations. Data on a set of four water storage...
Passenger alighting estimation is a critical task in public transport (PT) management, especially for entry-only Automatic Fare Collection (AFC) transport systems where passenger alighting are not recorded. Effective estimation methods are necessary for trip analysis and route planning, offering valuable insights into passengers’ mobility patterns and, subsequently, improving the quality of service. However, the stochastic nature of passenger behaviour challenges the degree of successful alig...
Breakwaters are built to promote sheltered areas, for people, ships, and harbour activities. In the design of rubble-mound breakwaters, a common type of breakwater in many countries, including Portugal, it is assumed that damage may occur in certain stretches of the structures, and therefore maintenance and repair works will be quite certainly needed. To successfully carry out these interventions, in a timely and cost-effective manner, the structures must be observed and monitored systema...
A presente dissertação teve como objetivo avaliar, por meio de abordagem experimental, o desempenho térmico de tintas térmicas em comparação a tinta convencional, quando aplicadas nas superfícies interiores e exteriores de paredes no período de arrefecimento. Após prospeção e recolha junto de empresas em Portugal, foram caracterizadas três tintas térmicas brancas e um primário térmico, comparativamente a uma tinta convencional branca. Inicial-mente onze provetes revestidos com as tintas e os ...
O presente relatório refere-se a um estudo de caracterização do comportamento do condutor no que se refere à utilização de dispositivos móveis durante a condução, nas principais categorias de estradas de Portugal, efetuado pelo LNEC no âmbito do projeto europeu Baseline, cofinanciado pela Comissão Europeia (CE). O projeto Baseline destinou-se ao desenvolvimento de indicadores do desempenho do sistema de transporte rodoviário na ótica da segurança (IDS) e nos quais se inclui um relativo à...
O Plano Ferroviário Nacional (PFN) constitui um plano estratégico de âmbito nacional que tem por finalidade definir a rede ferroviária que assegura as comunicações de interesse nacional e internacional. O PFN é enquadrador de projetos suscetíveis de terem efeitos significativos no ambiente, estando sujeito a avaliação ambiental no âmbito do Decreto-Lei n.º 232/2007, de 15 de junho, alterado pelo Decreto-Lei n.º 58/2011, de 4 de maio. Assim, foi desenvolvida em conformidade a avaliação am...
Urban resilience research covers multiple fields of study like earthquakes, floods, and tsunamis, amongst other types of disaster risks. Resilience evaluationsystems have been used to aggregate and calibrate multi-dimensional resiliencerelatedinputs. But these evaluation systems do not offer comprehensive outputs nor sufficient analytical capacity to support the design and implementation of city and community recovery and resilience plans. This study focuses on the strategic needs of resilie...
Natural disasters cause an average of 60,000 deaths per year. There was a total of 416 natural disasters worldwide in 2020. Resilience to disruption and quick recovery of the operational performance of buildings and infrastructure is critical to the continuous functioning of cities and communities. This requires recognition of critical weaknesses of urbanized society. This recognition can be mapped in terms of different dimensions that must be rated and weighted based on their relative import...
o obtain predictions closer to concrete behaviour, it is necessary to employ a particle model (PM) that considers contact softening. A bilinear softening contact model (BL) has been adopted in PM studies. Several limitations in PM predictions have been identified that may be due to BL assumptions. For this reason, this paper compares BL predictions with those obtained with more complex models to assess if PM predictions can be improved. As shown, it is possible to calibrate each contact ...
The resilience of buildings and civil engineering infrastructures has increasingly attracted the attention of different stakeholders, including engineering professionals from different areas, scientists, standardization bodies, investors and financial institutions, regulatory agencies, different user groups, as well as national and regional administrative services. This interest has motivated the development of methods for classifying the resilience of built assets, to identify aspects that ...
The recognition of the high costs of the vulnerabilities of cities and communities due to various types of disaster risks have helped build the business case for improving the investments of the quality and resilience of buildings and civil engineering works. This important issue has attracted the attention of several stakeholders, including engineering professionals from different fields, scientists, standardization bodies, investors and financial institutions, regulatory agencies, user grou...
Le propos de cette communication est la présentation des critères de conception des témoins sonores, de façon qu'ils puissent mesurer correctement les déformations et permettent d'évaluer indirectement les contraintes du béton. Ces critères essaient de fixer le champ de mesure et la raideur convenables à la mesure des déformations. On présentera des résultats expérimentaux et une simulation par ordinateur du comportement des témoins sonores installés au sein du béton.
A wave flume is used to study a scaled model of a stepped bottom dual-chamber Oscillating Water Column (OWC) installed onshore. Compared to traditional single-chamber OWCs, the use of dual-chambers is expected to widen the range of sea states in which the OWC is more efficient, and the step, in front of the first chamber, boosts the capturing energy capacity of the device. The Power Take-Off (PTO) system is modelled as an air opening in the pneumatic chambers. Several experiments combining re...
Performance and hydrodynamics of an array of Oscillating Water Column (OWC) Wave Energy Converter (WEC) integrated into a vertical breakwater is studied. The FLUENT® software, in which the numerical model is based on the Reynolds-Averaged Navier-Stokes equations and the Volume of Fluid method for free surface flow modeling, is used in a 3D numerical wave tank. Three vertical breakwater configurations subject to the action of incident regular waves with periods from 6 to 12 s are studied: norm...
Coastal hazards such as flooding and erosion can cause large economic and human losses. Under this threat, early warning systems can be very cost-effective solutions for disaster preparation. The goal of this study was to develop, test, and implement an operational coastal erosion early warning system supported by a particular method of machine learning. Thus, the system combines Bayesian Networks, and state-of-the-art numerical models, such as XBeach and SWAN, to predict storm erosion impact...
The internal structures and the hygroscopicity of bio-based boards consisting of giant reed (Arundo donax L.) and hazelnut shells as bio-aggregates, and a sodium silicate solution as the adhesive, were investigated. The aim was to evaluate the influence of each material (the bio-aggregates and adhesive) and their distributions in the boards on the final performance. By carrying out X-ray computed tomography, the internal structures and the porosities of the boards were determined, allowing ...
The search for innovative and sustainable solutions to improve the energy efficiency of the construction industry has been a hot topic for researchers due to the tremendous impact of insulator materials in the thermal comfort of buildings. In the present work, an innovative lightweight composite material with thermal insulation properties was developed, for the first time, by using cardoon particles and polyurethane. The formulation of the composite material was optimized in terms of car...
The introduction of stored product insect pests to new areas is facilitated by food trade among countries, and effective detection and monitoring programs are crucial for food security. The khapra beetle, Trogoderma granarium Everts is one of the most destructive insect species. In Portugal, T. granarium has been detected in 1988. However, no new data has been added to this information since that date. Floor traps with pheromones specific to T. granarium were used and placed inside ports, mil...
Arundo donax (giant reed or giant cane) is a widely available, perennial, invasive, non-food crop, present worldwide and employed for several uses, including building practices. Considering the increasing demand for sustainable building materials, A. donax can be an eficient solution. This study investigated its properties as a bio-aggregate mixed with a sodium silicate solution as an adhesive. A horizontal analysis that provided a general characterization of the composite was carried out. Th...
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