Artigos de Revista
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Artigos de Revista
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Performance Assessment of Reclaimed Asphalt Pavement (RAP) in Road Surface Mixtures
Considerable amounts of Reclaimed Asphalt Pavement (RAP) are produced every year,as the road network requires maintenance to ensure the safety and comfort of its users. RAP is a 100%recyclable material and a useful fit to be re-introduced into another cycle without downgrading itsfunctionality. Despite the current knowledge about the benefits associated with RAP use, it is not yetlargely applied in several countries. This paper aims to validate, on the basis of both short- and longtermmechanical behaviours, the application of a bituminous mixture with a high RAP incorporationrate (75%) in road pavement wearing courses. A crude tall oil rejuvenator was used. Both short- andlong-term oven ageing procedures were employed to simulate the ageing that occurs during mixtureproduction and in-service life, respectively. The tests for validating the RAP mixture as an alternativesolution comprised stiffness, resistance to fatigue, permanent deformation, and determination ofthe water sensitivity. Furthermore, the RAP bitumen mobilisation degree was evaluated and amixing protocol was established. In comparison with virgin bituminous mixtures, it was found that,in general, the high RAP mixtures presented similar or better behaviour. The ageing process hada hardening effect namely in terms of stiffness and resistance to permanent deformation, withoutsignificant effects on the resistance to fatigue and water damage.
Ano: 2021
Autor(es): Antunes, Vítor; Neves, J.; Freire, A. C.
Revista: Recycling
Editor: MDPI
Volume:
6, 32.
Keywords: rejuvenator; RAP; mechanical behaviour; bituminous mixture; ageing
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Performance Assessment System for Energy Efficiency in Wastewater Systems
Performance assessment is essential to effectively evaluate and monitor the activity of waterutilities, support decision making, and encourage continuous improvement. Performance assessmentsystems (PAS), covering several service objectives and criteria, have been successfully applied inwater supply and wastewater systems. Tailored approaches focusing on the assessment of the energyuse and efficiency in wastewater systems are still limited. This paper aims at the developmentand demonstration of a comprehensive PAS for energy efficiency, tailored for wastewater systems,incorporating criteria related to energy consumption, operation and maintenance (O&M) costs, andenvironmental impacts, such as untreated discharges and greenhouse gases emissions, among others.Management and control of excessive or undue inflows to these systems is specifically addressed byseveral novel criteria and metrics. The proposed PAS should be adapted by each utility to be alignedwith the objectives of the organisation and with the implemented asset management strategy. Theproposed approach and the resulting consolidated PAS are thoroughly described. Results from theapplication of the PAS to several Portuguese utilities are discussed. This PAS aims at contributing toa reliable and replicable process to assess energy efficiency in wastewater systems and to encouragea more rational energy management.
Ano: 2021
Número Páginas:
19 pp..
Autor(es): Jorge, C.; Almeida, M. C.; Covas, D.
Revista: Water 2021
Editor: MDPI
Volume:
13.
Keywords: Wastewater systems; Undue inflows; Performance metrics; Performance assessment systems (PAS)); Energy efficiency
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Performance Assessment System to Wastewater Utilities Strategic Planning
Urban water utilities face growing challenges in compliance with increasingly demanding legislation, tightening budgets, ageing personnel, decreasing infrastructure reliability, increasing operational costs, regulatory pressure, and climate change. Within this context, tracking the alignment of the performance with the mission and strategic objectives of the organization, based on reliable and up-to-date data, is of utmost importance to enable effective and continual improvement management. Organizational performance assessment in the water sector has been a topic of growing attention since the 1990s due to the increase in the role of regulators and tighter legislation. Proactive utilities are incorporating sustainability, resource efficiency, resilience, and continual improvement principles in their practices. Strategic planning provides the road map for management and interconnecting the different areas of the organization. An essential component of strategic management planning is the adoption of a tailored performance assessment system (PAS), allowing a better response to these challenges from the water utility management perspective. This paper presents a novel PAS at the strategic level, which was tested and validated with wastewater utilities, in a co-creation process. The proposed PAS fully adopts the objectives recommended in international standards, with a corresponding set of criteria and metrics, and a validated proposal of reference values for the metrics.
Ano: 2021
Número Páginas:
20 pp..
Autor(es): Almeida, M. C.; Brito, R.; Jorge, C.; Cardoso, M. A.
Revista: Water 2021
Editor: MDPI
Volume:
Volume 13, Issue 18.
Keywords: Wastewater utilities; Urban water systems; Strategic planning; Performance metrics; Performance assessment systems (PAS)
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Performance of a Salt-Accumulating Substitution Lime Render for Salt Laden Historic Masonry Walls
Salt crystallization is one of the main decay processes in historic masonry mortars, and climate change can worsen the salt weathering effects on those materials as result of, e.g., more often rain falls, more intense solar radiation and sea level rise. In this paper, the effectiveness and durability of a substitution
Ano: 2021
Autor(es): Fragata, A.; Veiga, M. R.; Velosa, A.
Revista: MDPI - Heritage
Editor: Heritage
Keywords: rising damp; soluble salts; historic buildings; full-scale masonry; accumulating render
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Performance parameters of ETICS: Correlating water resistance, bio-susceptibility and surface properties
The use of External Thermal Insulation Composite Systems (ETICS) significantly increased in the last decades due to their enhanced thermal properties, low installation cost and ease of application, not only innew constructions but also for thermal retrofitting of building facades. These multilayer rendering systemsare constantly exposed to weathering agents and anthropic factors which can lead to physicalmechanicaland aesthetical anomalies and thus affect their durability. However, possible synergeticeffects among these agents are often neglected by international technical documents on the evaluationof the effectiveness and durability of ETICS. With the aim of filling this gap, moisture transport properties(capillary water absorption, water vapor permeability, water absorption under low pressure, and dryingkinetics), thermal conductivity, mould susceptibility and surface properties (color, gloss, and roughness)of twelve commercially available ETICS were assessed and discussed. Possible links between these factorswere analyzed and ETICS performance parameters were defined. Results demonstrate that a deeperknowledge of the correlation among ETICS properties can effectively contribute to the evaluation ofthe efficiency and long-term durability of these systems.
Ano: 2021
Autor(es): Parracha, J.; Borsoi, G.; Flores-Colen, I.; Veiga, M. R.; Lina Nunes; Dionísio, A.; Gomes, M.; Faria, P.
Revista: Construction and Building Materials
Editor: Elsevier
Volume:
272:121956.
Keywords: Performance parameters; Mould susceptibility; Thermal conductivity; Surface properties; Moisture transport; ETICS
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Performance parameters of ETICS: Correlating water resistance, bio-susceptibility and surface properties.
The use of External Thermal Insulation Composite Systems (ETICS) significantly increased in the last decades due to their enhanced thermal properties, low installation cost and ease of application, not only in new constructions but also for thermal retrofitting of building facades. These multilayer rendering systems are constantly exposed to weathering agents and anthropic factors which can lead to physical-mechanical and aesthetical anomalies and thus affect their durability. However, possible synergetic effects among these agents are often neglected by international technical documents on the evaluation of the effectiveness and durability of ETICS. With the aim of filling this gap, moisture transport properties (capillary water absorption, water vapor permeability, water absorption under low pressure, and drying kinetics), thermal conductivity, mould susceptibility and surface properties (color, gloss, and roughness) of twelve commercially available ETICS were assessed and discussed. Possible links between these factors were analyzed and ETICS performance parameters were defined. Results demonstrate that a deeper knowledge of the correlation among ETICS properties can effectively contribute to the evaluation of the efficiency and long-term durability of these systems.
Ano: 2021
Autor(es): Parracha, J.; Borsoi, G.; Flores-Colen, I.; Veiga, M. R.; Nunes, L.; Dionísio, A.; Gomes, G. T. B.; Faria, P.
Revista: Construction and Building Materials
Editor: ScienceDirect
Volume:
272.
Keywords: ETICS
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Physical and Mechanical Performance of Coir Fiber-Reinforced Rendering Mortars.
Coir fiber is a by-product waste generated in large scale. Considering that most of these wastes do not have a proper disposal, several applications to coir fibers in engineering have been investigated in order to provide a suitable use, since coir fibers have interesting properties, namely high tensile strength, high elongation at break, low modulus of elasticity, and high abrasion resistance. Currently, coir fiber is widely used in concrete, roofing, boards and panels. Nonetheless, only a few studies are focused on the incorporation of coir fibers in rendering mortars. This work investigates the feasibility to incorporate coir fibers in rendering mortars with two different binders. A cement CEM II/B-L 32.5 N was used at 1:4 volumetric cement to aggregate ratio. Cement and air-lime CL80-S were used at a volumetric ratio of 1:1:6, with coir fibers were produced with 1.5 cm and 3.0 cm long fibers and added at 10% and 20% by total mortar volume. Physical and mechanical properties of the coir fiber-reinforced mortars were discussed. The addition of coir fibers reduced the workability of the mortars, requiring more water that affected the hardened properties of the mortars. The modulus of elasticity and the compressive strength of the mortars with coir fibers decreased with increase in fiber volume fraction and length. Coir fiber
Ano: 2021
Autor(es): Veiga, M. R.; Brito, J.; Pederneiras, C.
Revista: Materials
Editor: MDPI
Volume:
14, assunto 4.
Keywords: vegetable fiber; fiber-reinforced mortar; cement and cement-lime mortars; sustainability; render
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Por uma nova
Depois de uma pequena introdução minimamente justificativa do caminho, aqui proposto, no sentido de se enquadrar o que se julga ser a essencial ou vital qualidade arquitectónica e, portanto, humana e de uso, que tem de caracterizar a nova Habitação de Interesse Social/Habitação a Custos Controlados (HIS/HCC) a realizar, em Portugal, apontam-se alguns aspetos qualitativos julgados fundamentais na promoção de habitação e, particularmente, da referida
Ano: 2021
Número Páginas:
20p.
Autor(es): Baptista Coelho, A.
Revista: Infohabitar
Editor: GHabitar - Associação Portuguesa para a Promoção da Qualidade Habitacional (GHabitar APPQH)
Volume:
Infohabitar, Ano XVII, n.º 785
Keywords: infohabitar; urbanismo; futuro da habitação social; habitação social; arquitectura; habitação
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Potencialidades e problemas a considerar nas circulações domésticas infohabitar # 788
Neste artigo, dedicado à temática do vestíbulo de entrada na habitação, faz-se, de início, um enquadramento e uma breve introdução geral aos espaços domésticos, seguindo-se uma reflexão sequencial sobre as seguintes matérias específicas: (i) aspetos motivadores ligados aos espaços de circulação domésticos; (ii) problemas correntes nos espaços de circulação domésticos; e (iii) questões e ideias frequentemente levantadas (dimensionais e outras) nestes espaços.
Ano: 2021
Número Páginas:
12p.
Autor(es): Baptista Coelho, A.
Revista: Infohabitar
Editor: GHabitar - Associação Portuguesa para a Promoção da Qualidade Habitacional (GHabitar APPQH)
Volume:
Infohabitar, Ano XVII, n.º 788
Keywords: infohabitar; circulações domésticas; arquitectura; habitação
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Practical Methodology for Forecasting the Impact of Changes in Influent Loads and Discharge Consents on Average Energy Consumption and Sludge Production by Activated Sludge Wastewater Treatment.
This paper proposes a simple and easy-to-use methodology for forecasting the impact of changes in influent chemical oxygen demand (COD) and in the emission limit values (ELVs) of COD and total nitrogen on average energy requirements for aeration and sludge production by activated sludge wastewater treatment plants (WWTPs). The methodology is based on mass balances of sludge production and oxygen requirements for carbonaceous material biodegradation and/or nitrification, oxygen transfer and aeration equipment efficiency. Using average values of historical data of regular monitoring (water quality and operating conditions) WWTP-specific equations of oxygen requirements, energy consumption and sludge production are derived as a function of influent COD and influent N-total, which may be used to quantify the impact of influent and ELV changes. The methodology was tested in five extended aeration WWTPs for three scenarios established by the utility. The results show that increasing influent COD, from 900 to 1300 mg/L, for example, significantly increases the energy consumption by 49% and sludge production by 53%. For influent 54
Ano: 2021
Número Páginas:
11 pp..
Autor(es): Silva, C.; Rosa, M. J.
Revista: Sustainability
Editor: MDPI
Volume:
Volume13, Issue 21.
Keywords: Sludge; Regulation; WWTPs; Energy; Oxygen
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