ESTGV - DEC - Artigo em revista científica, indexada ao WoS/Scopus
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- The Role of Metallic Connections in the Global Behavior of Timber Frame Structural System of Tabique WallsPublication . Padrão, José; Pinto, Jorge Tiago Queirós da Silva; Arêde, António; Guedes, JoãoIn order to perform a correct and efficient rehabilitation of old building, it is required to know the materials used, their main properties as well as the construction process. Tabique Walls (TW) are primary building components of many constructions in the historic center of Viseu and their function, in addition to being used as partitioning elements (the most common in Portugal), is to be part of the main structure of buildings. In this sense it is essential to understand how the TW interconnect with each other and with the other main structural elements of buildings, namely the floors and the stone masonry walls. The important role of metallic connectors in the realization of these bonds is emphasized. This paper presents the research carried out in several buildings of the historic center of Viseu. Several constructive solutions found are detailed, associating the shapes and dimensions of the connectors to their function, and results are presented out of a primary campaign of laboratory tests carried out to define their mechanical properties. The knowledge obtained allows a better understanding of the overall structural behavior of these buildings and the role of the TW in that behavior.
- Model for Health Risk Assessment in Portuguese Housing SpacesPublication . Pinto, Manuel; Pastorinho, Manuel Ramiro; Lanzinha, João; Monteiro, MarisaCurrently, people spend most of their time inside their homes. However, poor conditions in terms of comfort and quality of the indoor environment can pose high risks to the inhabitants’ health. Therefore, a good quality environment is essential, since, in addition to the hazards present in indoor air (e.g., particles, (S)VOCs, CO, radon and tobacco smoke), extreme temperatures, relative humidity levels, pests (e.g., mold, dust mites and bioaerosols), noise, airborne infectious agents (e.g., SARS-CoV-2) and contamination through water and soil can cause physical injuries, respiratory diseases, damage to multiple organ systems as well as harmful effects on the mental health of the occupants. Faced with this requirement, housing evaluation models were studied together with the main types of risk that could affect the health of the inhabitants, with the objective of proposing a new evaluation model for housing health and safety risks, fitted to the occupants, and especially suitable for Portuguese dwellings, although applicable in other geographical contexts. As a result of this analysis, this article proposes a new model for evaluating health and safety risks in housing, applicable in Portugal, supported by an inspection form and, as the main difference from the existing models, parameter measurements, providing complementary data for the evaluation. This model was created based on a set of functional and regulatory requirements that were identified for the healthy use of living spaces. Twenty-eight hazards were identified, and the respective risk factors were assessed using different processes and target demographics, including visual inspection, parameter measurements, occupants’ age and location and age of housing. In order to validate the model and determine its usefulness, it was applied to a set of houses with different construction dates, locations and occupants. This exercise enabled the identification of hazard classes and the calibration and fine tuning of the model application. Finally, proposals for future work are presented in order to create a base of evolution for the model.
- Quality of the Indoor Environment in Elderly Care Centers in Two Cities in Central Portugal: Viseu and CovilhãPublication . Pinto, Manuel; Lanzinha, João; Viegas, João; Infante, Catarina; Freire, TiagoAssessments of Indoor Environment Quality (IEQ) present a very significant challenge when analyses are undertaken mainly in buildings that include a particularly sensitive and vulnerable population, such as elderly people. In order to maintain an indoor environment that is adequate for occupants, it is necessary to comply with a set of requirements (for TVOC, the Portuguese threshold values) regarding concentrations of airborne pollutants and hygrothermal comfort conditions. This paper studies IEQ in compartments in 3 buildings in two cities in central Portugal, Viseu and Covilhã, which hold elderly care centers. The following environmental parameters were continuously recorded: air temperature, relative humidity, concentration of carbon dioxide, formaldehyde, and total volatile organic compounds and ventilation rates. An analysis of the obtained results was performed, taking recommended guidelines and threshold values into account, thus making it possible to evaluate the IEQ conditions and hygrothermal comfort in the selected indoor spaces. On the basis of the conclusions reached and the observed problems of hygrothermal comfort and indoor pollutants in the indoor spaces, a number of recommendations are proposed, specifically in terms of climate control, ventilation, and maintenance, in order to obtain an overall improvement of IEQ.
- Kindergartens and nurseries in central portugal. assessments of indoor environment qualityPublication . Pinto, Manuel; Lanzinha, João; Viegas, João; Infante, Ana; Freire, TiagoThe Indoor Environment Quality study takes on a very significant challenge when analyzed, mainly, in buildings that encompass a more sensitive and susceptible type of population, as is the case of children. To comply with a set of requirements, namely the concentration of pollutants and the conditions of hygrothermal comfort, is a necessary condition to keep an interior environment suitable for the permanence of the occupants. A research project, that studied Indoor Environment Quality in four buildings which hold nurseries and kindergartens, was carried out in two cities in central Portugal, Viseu and Covilhã. The following main conclusions may be drawn: most compartments are not comfortable in terms of ambient temperature, but the relative humidity has reasonable values. Air change rates generally have low values and the measured pollutants have worrying values. Based on the observed problems and reached conclusions, some recommendations are proposed.
- A contribution for the quantification of the influence of windows on the airtightness of Southern European buildingsPublication . Almeida, Ricardo; Ramos, Nuno M.M.; Pereira, Pedro F.Adequate airtightness levels are fundamental for the indoor environmental quality and energy efficiency of buildings. The quantitative characterization of expected leaks of common building elements is useful for practitioners that intend to improve building enclosures for airtightness optimization. This study intends to contribute to the quantification of the permeability of windows with a focus on the Southern European context of low airtightness in heavy construction buildings, where windows play an important role. A large experimental investigation was therefore carried out in 23 spaces, establishing three possible set-ups (nothing sealed, window sealed and window and roller-shutter sealed), using the fan pressurization method. A total of 104 tests were performed. Results revealed that the windows’ permeability indices ranged from 4.8 to 96.4 m3/(h m2) and from 1.2 to 30.8 m3/(h m), with average values of 28.7 m3/(h m2) and 8.9 m3/(h m), the roller-shutter contribution can be highly variable; also the year of construction, the frame material and the opening system are the key parameters for the airtightness of windows
- Driving around turbo-roundabouts vs. conventional roundabouts: Are there advantages regarding pollutant emissions?Publication . Fernandes, Paulo; Pereira, S. R.; Bandeira, J. M.; Vasconcelos, Luís; Bastos Silva, AnaThis paper addresses the impact of turbo-roundabouts located in urban areas on pollutant emissions using field measurements of vehicle activity data and road congestion levels. The research also compares the emissions of vehicles moving along a turbo-roundabout and a conventional multi-lane roundabout. Based on field measurements taken at turbo-roundabouts without curb dividers located in Grado (Spain) and multi-lane roundabouts in Aveiro (Portugal), three representative speed profiles for each speed trajectory were identified: no stop (I), stop once (II), and multiple stops (III). This study also develops discrete models for turbo-roundabouts and multi-lane roundabouts in which the relative occurrence of those speed profiles is expressed as a function of the entry and conflicting traffic flows. The Vehicle Specific Power (VSP) methodology is then employed to estimate second-by-second pollutant emissions. This study tests the hypotheses that emissions are impacted by the differences in: 1) the characteristics of speed profiles in each movement; 2) the volumes of entry and conflicting flows; 3) the overall saturation level; and 4) the transportation facility considered (turbo-roundabout /multi-lane roundabout). Considering the selected case studies and traffic demands, vehicles at turbo-roundabouts generated more emissions (15-22%, depending on the pollutant) than multi-lane conventional roundabouts, especially under medium and high congested levels. These findings suggest that there are no advantages in implementing turbo-roundabouts from an environmental point of view, even in no saturated conditions.
- Validation of the Surrogate Safety Assessment Model for Assessment of Intersection SafetyPublication . Vasconcelos, Luís; Neto, Luís; Seco, Álvaro; Silva, Ana BastosThe surrogate safety assessment model (SSAM) is a software application that reads trajectory files generated by microscopic simulation programs and calculates surrogate measures of safety. This approach eliminates the subjectivity associated with the conventional conflict analysis technique and allows assessment of the safety of a facility under a controlled environment before accidents occur. The specific goal of this research was to validate SSAM as a tool for accident prediction at urban intersections. Two methods were used for validation. The first method compared the simulated number of conflicts from the use of SSAM and the predicted number of injury accidents from analytic models in three reference intersection layouts (four-leg priority intersection, four-leg staggered intersection, and single-lane roundabout). The second method compared SSAM results with conflicts observed on site in four real intersections: two priority ones and two roundabouts. The results indicate that, despite some limitations related to the nature of current traffic microsimulation models, SSAM analysis is an extremely promising approach to assessing the safety of new facilities or innovative layouts.
- Turboroundabouts: Assessment of Intersection Capacity, Safety, and EmissionsPublication . Vasconcelos, Luís; Silva, Ana Bastos; Seco, Álvaro; Fernandes, Paulo; Coelho, MargaridaA “turboroundabout” is a variation of the conventional multilane roundabout in which spiral road markings and raised lane dividers force drivers to follow a specific path according to their intended destination. This geometry eliminates weaving and cut-in conflicts by guiding drivers continuously from entry to exit. Turboroundabouts were conceived with the main aim of improving safety, but their practical benefits are relatively unknown. Likewise, the few existing studies on turboroundabouts do not allow definitive conclusions to be drawn about the delay and emissions performance characteristics of turboroundabouts; further research is needed. This research focused on the use of appropriate modeling methodologies to understand the effects of turboroundabouts on capacity, safety, and emissions in comparison with the effects of conventional singlelane and double-lane roundabouts. The results indicate that turboroundabouts have capacity levels comparable to those of two-lane roundabouts but are less robust concerning the directional split of the entry traffic; turboroundabouts lead to fewer traffic conflicts, but the traffic conflicts that do occur are more severe. The results also show that the implementation of turboroundabouts provides no advantages for emissions when the main concerns are carbon dioxide and oxides of nitrogen.