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- Enhancing Civil Engineering teaching through 3D Computer Aided DesignPublication . Gonçalves, Jorge H.G.; Santos, Bertha3D interpretation of 2D drawing is not easy for most of the Civil Engineering first-year students. Some do it naturally but most need to be trained to master this skill. In this paper, the implemented teaching methodologies aiming to facilitate the acquisition of three-dimensional project visualization skills are presented. These methodologies were developed during the last two years targeting first-year Civil Engineering students at the University of Beira Interior (Portugal). After a first contact with 2D project representation through manual drawing, students progressively elaborate computer-aided design (CAD) project starting with simple 2D drawings and culminating with a 3D project of a pre-existing building. Students are also motivated to improve their 3D graphic representation skills through a classroom contest where the winning project is printed in 3D. The training in 2D and 3D graphic representation is complemented during the second year with several in situ surveys and computer-aided drawing of topographic data. This approach proved to be very interesting for competence acquisition, qualifying students for a better 3D representation and interpretation. Students also found this methodology to be motivating.
- Modelling Road Work Zone Crashes’ Nature and Type of Person Involved Using Multinomial Logistic RegressionPublication . Vieira, Adriana; Santos, Bertha; Picado-Santos, LuisThe sustainable development goals “Good health and well-being” and “Sustainable cities and communities” of the United Nations and World Health Organization, alert governments and researchers and raise awareness about road safety problems and the need to mitigate them. In Portugal, after the economic crisis of 2008–2013, a significant amount of road assets demand investment in maintenance and rehabilitation. The areas where these actions take place are called work zones. Considering the particularities of these areas, the proposed work aims to identify the main factors that impact the occurrence of work zones crashes. It uses the statistical technique of multinomial logistic regression, applied to official data on road crashes occurred in mainland Portugal, during the period of 2010–2015. Usually, multinomial logistic regression models are developed for crash and injury severity. In this work, the feasibility of developing predictive models for crash nature (collision, run off road and running over pedestrians) and for type of person involved in the crash (driver, passenger and pedestrian), considering only one covariate (the number of persons involved in the crash), was studied. For the two predictive models obtained, the variables road environment (urban/rural), horizontal geometric design (straight/curve), pavement grip conditions (good/bad), heavy vehicle involvement, and injury severity (fatalities, serious and slightly injuries), were identified as the preponderant factors in a universe of 230 investigated variables. Results point to an increase of work zone crash probability due to driver actions such as running straight and excessive speed for the prevailing conditions.
- EU and Portuguese cycling strategy for sustainable urban mobilityPublication . Matias, Isabel; Santos, Bertha; Gonçalves, Jorge; Kempa, Jan; Chmielewski, JacekSustainable mobility has become a central topic for reflection and debate when defining active urban policies. In opposition to traditional mobility focused on private cars, sustainable urban mobility aims to respond to society's travel needs of comfort, safety, and time with healthy, environmental-friendly, and economical solutions. Soft mobility modes, especially cycling, are an alternative capable of reversing the trend on private car use in urban areas. Cycling has been playing an important role in urban sustainable development in the last decade, being one of the main strategies of urban mobility plans. The present study presents a review of the main European Union (EU) and Portuguese cycling strategies. The methodological approach includes the collection and analysis of the main EU and Portuguese documents discussing the challenges and options for urban mobility, especially those focused on cycling. These strategies aim to promote the use of bicycles on commuting trips and the reduction of greenhouse gas (CO2) emissions, thus contributing to a more sustainable urban environment and healthier communities, the main objectives of the EU’s cycling strategies. Conclusions point out that it was mainly in the last 10 years that specific plans for the promotion of the use of bicycles and other soft modes emerged in Portugal, but only in the last 5 years, financing conditions were created to support municipalities in this task.
- Spatial Multi-Criteria Analysis for Road Segment Cycling Suitability AssessmentPublication . Santos, Bertha; Passos, Sílvia Valentina González de; Gonçalves, Jorge H.G.; Matias, IsabelThe shift to low-emission mobility, embedded in a growing need for sustainable development, makes soft modes a highly promoted transport alternative in national and international mobility policies. Soft mobility modes, especially cycling, is an alternative capable of reversing the trend of private car use in urban areas, being one of the main strategies of Sustainable Urban Mobility Plans (SUMP). Several factors can influence travel mode choice, between them, demographic, economic, land use, travel distance and time, and climatic and physical factors are the most reported in the literature. This study presents a framework of the main European cycling strategies and focuses on the development of a methodological approach to assess the cycling suitability of existing road networks. The approach is based on a spatial multi-criteria analysis that combines population density, trip generation points service areas and road characteristics (hierarchy and slope). Consideration of the topography was particularly relevant in the cycling suitability model definition. The model was tested in the hillside city of Covilhã (Portugal) and compared with the recently planned and implemented city cycling network. The main conclusions point to the adequacy, flexibility, and applicability of the proposed model by municipalities, contributing to a more sustainable urban environment and healthier communities. Results obtained in the Covilhã case study also denote the possibility of implementing cycling mobility in hillside cities, especially using e-bikes. For future works, an expansion of the approach is proposed to include a detailed and sustained cycling network definition model and a process to assess cycling routes hierarchy/solutions.
- Pedestrian Road Accident Index for Municipalities: The Portuguese CasePublication . Santos, Bertha; Carvalheira, CarmenPortuguese road traffic accidents statistics show that the number of accidents with fatalities and serious injuries has in general decreased in recent years. However, the number of accidents involving pedestrians is still high when compared with those observed in other countries of the European Union. In order to assess this problem, an index of pedestrian road traffic accidents for municipalities that could be used in decision-making about pedestrian safety measures is proposed. The use of absolute values of accidents involving pedestrians (running over) does not allow itself a reliable comparison of pedestrian safety level between municipalities. In this sense, the approach proposed uses the information available in the Portuguese database PORDATA to calculate a municipal index that takes into account the degree of exposure of pedestrians to accident, based on national and municipal resident population annual growth rates and number of pedestrian's casualties. This index allows to identify the municipalities with unfavourable deviation to national numbers of road accidents involving pedestrians (per 10000 inhabitants), supporting the plan and allocation of human and economic resources for the diagnosis, definition and implementation of safety measures. The results obtained can be visualized in a GIS for a more comprehensive comparison between municipalities. The analyses performed for Portugal showed that, in general, municipalities with higher resident population annual growth rates, located mostly along the coastline and in more consolidated urban areas, tend to present better index values, which points to the need to intervene in less consolidated areas.
- Teaching methodologies in civil engineering: a multidisciplinary approachPublication . Virtudes, Ana L.; Rodrigues, Ilda Inácio; Santos, Bertha; Pop, MariaNowadays universities are rethinking their teaching methodologies not only in order to adapt to the use of new technologies, such as the ICT (information and communication technologies) or the GIS (Geographic Information Systems) but also in order to advance the international students towards a multidisciplinary approach. Thus, this article is the result of a multidisciplinary approach gathering scholars from Portugal and Romania, presenting a set of several teaching methodologies used on the domains of civil engineering. It is based on the experience of the University of Beira Interior (UBI) in Portugal and the Faculty of Constructions, Cadastre and Architecture of the University of Oradea (UO) in Romania. Among other descriptions, the conclusions show that there are several different and common aspects in between the Portuguese and the Romanian experiences. Regarding the common aspects there is the need of finding new teaching methodologies in order to consider the different backgrounds of the international students coming from several countries and continents, having diverse high educational systems. Thus, the international students are encouraged to work together and to actively participate in the development, presentation and discussion of their scientific findings.
- GIS-Based Transport Accessibility Analysis to Community Facilities in Mid-Sized CitiesPublication . Tomé, André Filipe Saraiva Coelho; Santos, Bertha; Carvalheira, CarmenTransport accessibility is an important issue for the sustainable development of cities. This work presents a GIS-based accessibility analysis approach that can be applied to assess accessibility to community facilities in medium-sized cities using publicly available data. For that purpose, a case study was developed using the road network and public transport data from Covilhã municipality, in Portugal. Data collected on websites were treated and organized to build the network dataset and perform network analyses with the aid of the ArcGis® Network Analyst extension (creation of service areas and Origin-Destiny (OD) cost matrices). Four accessibility evaluation analyses were performed for two transport modes: accessibility to the municipality main community facilities by private and urban public transport (isochronous and OD matrices), by inter-urban public transport (time); and accessibility by private transport between civil parishes (isochronous and OD matrices). The population and the territory covered by different travel times were also determined. The case study results showed that the accessibility in Covilhã is quite reasonable, either using private transport inside the municipality (maximum 30 minutes for covering nearly 95% of the resident population and 83% of the territory), or urban public transport inside the urban perimeter (maximum 50 minutes). However, the periphery civil parishes of the municipality have lower levels of accessibility for inter-urban public transport (reaching 115 minutes). The utility of the approach was validated through the results obtained in the case study, where it was possible to observe patterns of accessibility across the municipality for the considered modes, making it possible to improve the overall accessibility through the identification of priority areas of intervention.
- GIS-based inventory for safeguarding and promoting Portuguese glazed tiles cultural heritagePublication . Santos, Bertha; Gonçalves, Jorge H. G.; Almeida, Pedro G.; Martins-Nepomuceno, Ana M. T.Innovative, non-invasive, digital, and cost-effective instruments for systematic inventory, monitoring and promotion are a valuable resource for managing tangible and intangible cultural heritage. Due to its powerful and effective inventory and analysis potential, which allows supporting central and local entities responsible for cultural heritage management, Geographic Information Systems (GIS) have proven to be an appropriate information technology for developing these kinds of instruments. Given the above, this work aims to introduce a GIS-based instrument to support inventorying, safeguarding, tourism, and cultural promotion of the traditional Portuguese glazed tile (‘azulejo’, in Portuguese) to raise general awareness of the importance of this unique Portuguese heritage. To the best of the authors’ knowledge, there is no other instrument available with inventory and safeguarding management functions that is accessible and affordable, developed to be used at a municipal level and that contributes to the enrichment of the cultural and tourist information. Information from 70 tile works located in the Portuguese city of Covilhã was used to test the proposed GIS tool, resulting in a georeferenced alphanumeric, graphical, image and drawing inventory and in three pedestrian routes for touristic and cultural heritage promotion. The results were validated by both the research team and the municipality of Covilhã, foreseeing its expansion and daily use in the management of the heritage of the traditional Portuguese glazed tile. The proposed instrument can be replicated in other locations and easily implemented and managed by municipalities or institutions dealing with the protection of cultural heritage.
- Research of the impact of bumps on vehicle speedsPublication . Kempa, Jan; Chmielewski, Jacek; Prandol, Dominika; Santos, Bertha; Gonçalves, JorgeThe paper presents the results of research on the impact of selected types of speed bumps, located in the streets of the city road network, on the instantaneous speed of passenger cars in free flow traffic conditions. The research considered different speed bumps. All types of speed bumps occurred to be very effective in a traffic calming. The applied parametric tests of a statistical significance showed that, for the sake of mathematical statistics, the differences in the instantaneous speed of vehicles at the speed bumps are significant in relation to the instantaneous speed of vehicles on the inter-junction sections. The instantaneous speeds of passenger cars at speed bumps were over 60% lower in relation to the speeds achieved by drivers of those cars in the inter-junction sections.
- Prioritization of railway proximity interventions: The case of the Portuguese railway networkPublication . Gonçalves, Jorge H.G.; Santos, Bertha; Oliveira, AlexandraThe mission of a national railway administration is to provide conditions for the efficiency, competitiveness, and sustainability of rail transport. In this context, this study aims to fill a gap in rail infrastructure management through the adoption of multi-criteria decision analysis (MCDA) and quadrant analysis to obtain a priority evaluation matrix for railway proximity interventions (small-scale, medium/short-term interventions close to the customer). In order to achieve the network manager’s general goals, an extensive collection of railway activities and an iterative procedure, which combines the strategic vision of different operational units, were adopted. Moreover, a multi-criteria and hierarchy process based on quadrant analysis to select the interventions with greater potential to achieve a set of objectives over five years, was defined. The proposed methodology was applied in a real case within the Infrastructures of Portugal, SA competencies and needs (Portuguese railway network manager). The identification of a set of fundamental interventions from a technical and non-technical point of view was performed and allowed a more efficient resource allocation. This allowed listing the most relevant interventions in both technical and non-technical perspectives (19–25% of total interventions) and also from an essentially technical point of view (27–31% of total interventions). These correspond to the interventions located in the two most relevant quadrants (Q1 – develop and Q2 – validate) and to more than 70% of the total investment. The presented approach and results constitute the first three iterations to be monitored and evaluated in the revision of future plans in order to increase reliability levels, safety conditions and service quality. The methodology has the potential to be adapted to different scenarios (in particular budgetary) and future proximity intervention plans, thus being an essential decision support tool for an efficient allocation of the company’s resources.
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