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- Caracterização físico-química de cascas de amêndoas e nozes para valorização em obras de terraPublication . Marchiori, Leonardo; Nouioua, Thamer; Morais, Maria Vitoria; Silva, Flora Cristina Meireles; Albuquerque, Antonio; Andrade Pais, Luís; Cavaleiro, VictorOs resíduos agroindustriais têm sido investigados para aplicações de engenharia devido à sua elevada produção e ausência de valorização adequada face aos requisitos legais e de políticas e metas de sustentabilidade. O estudo das caraterísticas das cascas de amêndoas (CA) e nozes (CN) têm suscitado interesse na comunidade científica para desenvolver materiais alternativos e inovadores, com design sustentável, em várias aplicações. Este trabalho tem como objetivo caracterizar e analisar as propriedades físico-químicas de CA, CN e de um solo residual, bem como de duas misturas de cada resíduo com o solo, com 10% e 40% de cascas, para eventual aplicação em obras de terra. Os resultados mostraram que ambos os resíduos poderiam ser incorporados no solo para torná-los mais granulares e reduzir a densidade específica, além de terem potencial para remover alguns poluentes da água devido à presença de aluminosilicatos com K2O, CaO e SiO2. Esta aplicabilidade poderia reduzir a utilização de solos naturais em obras de terra, a incineração de ambas as cascas e sua deposição em aterros sanitários, podendo promover a sua valorização e criar produtos baseados em resíduos no âmbito da economia circular. No entanto, são necessários estudos adicionais para uma melhor compreensão do seu potencial para utilização em obras de terra, nomeadamente ensaios de lixiviação, degradação e adsorção.
- Evaluation of the potential use of water treatment sludge (WTS) as a waterproofing material for waste containment earthworksPublication . Marchiori, Leonardo; Studart, André; Morais, Maria Vitoria; Albuquerque, António; Cavaleiro, VictorIndustrial wastes’ incorrect disposal can cause groundwater and soils contamination. In this aspect, the water treatment sludge (WTS) appears as a potential residue to be valorized within soils in order to enhance wastes’ stabilization while mitigating its environmental impacts. Therefore, geotechnical and chemical evaluations were conducted for assessing WTS’s potential as a waterproofing agent for earth works, considering their impacts on the properties of the analyzed clayey soil for assessing possible soil’ reinforcement through a further investigation. Found results on the WTS characterization have shown a high percentage of fines, which contributes for the reduction of the soil’s plasticity. In addition, its chemical composition is compatible with pozzolanic characteristics while being possible to associate the analyzed WTS with materials already used in earth works. These results indicate a solid beginning for a complete characterization of the WTS and its stabilization within soils as they indicate possible reinforcement of clayey soils and use for liners application, which have yet to be confirmed by in-depth investigations around resistance and permeability properties.
- Recycling pulp mill sludge to improve soil fertility using GIS toolsPublication . Ribeiro, Paulo; Albuquerque, Antonio; Quinta-Nova, Luís; Cavaleiro, VictorPulp mill sludge produced in the Cova da Beira region (Portugal) contains organic matter (11-47%), nitrogen (38-2560 mg N/kg) and phosphorus (167-370 mg P/kg), which may be valuable for increasing soil productivity. The levels of heavy metals are below the limits recommended by legislation and the amount of nitrogen and phosphorous to be introduced in soils does not present a risk for nutrient leaching. After identifying the environmental and technical restrictions on its application, an area of 1650 ha was identified where the sludge can be applied in forage crops, fruit trees, olive groves and vineyards. A suitable area was also found for a biosolids storage centre. The use of GIS allowed to define a sludge application index and to produce land-use suitability maps, which can be useful for sludge management.
- Analysis of the chemical properties of almond and walnut shells for use in earthworksPublication . Nouioua, Thamer; Marchiori, Leonardo; Albuquerque, Antonio; Silva, Flora Cristina Meireles; Pais, Luís Andrade; Cavaleiro, VictorAlmond (AS) and walnut shells (WS) have attracted the interest of scientific community due to the possibility of developing innovative eco-friendly materials. This work aims to analyze the chemical characteristics of AS, WS, a residual granitic soil (RGS) and two mix-tures of waste:soil (10:90% and 40:60%) for evaluating their compatibility for earthworks application. Results show that both wastes could be incorporated into RGS for improving its properties and additionally can remove some water pollutants due to the presence of K2O, CaO and SiO2. This application could reduce the need to use soil natural resources, incineration of both wastes or their deposition in sanitary landfills and can promote their valorization and even create value-added products in the scope of the circular economy. However, additional studies are needed for a better understanding of their potential for using in earthworks, namely leaching, solubilization and adsorption experiments.
- Industrial solid wastes acting as barrier material for storing solid wastes and wastewaters - A critical reviewPublication . Marchiori, Leonardo; Albuquerque, Antonio; Cavaleiro, VictorClays and geosynthetic materials are commonly applied as low hydraulic conductivity layers and environmental protection barriers for storing solid wastes and wastewaters for both cover and bottom impermeabilization of geotechnical structures. However, due to a future shortage of clay materials and their high transport costs, in addition to geosynthetics generating more waste and presenting high costs, two needs emerge: reducing the amount of waste generated and developing strategies for preventing this waste from infiltrating the soil and ground water. One of the possible solutions consists in the use of some geotechnically applicable residues to prevent soil infiltration. Many by-products have been extensively studied as to their suitability as a geomaterial and showed promising results for use in liners. The most significant factors that depend on hydraulic conductivity are index, compaction, and compressive properties, so, in this aspect, hydraulic, mechanical, physic-chemical, and mineralogical properties determine the valorization, or not, of the waste as liner material. Industrial wastes and geocomposite acting as hydraulic barriers material and its geotechnical properties were reviewed and analyzed lack of research and future investigations suggestions.
- Teaching Methodologies in Spatial Planning for Integration of International StudentsPublication . Virtudes, Ana L.; Cavaleiro, VictorNowadays, the spread of international exchanges is growing among university students, across European countries. In general, during their academic degrees, the high education students are looking for international experiences abroad. This goal has its justification not only in the reason of pursuing their studies, but also in the desire of knowing another city, a different culture, a diverse way of teaching, and at the same time having the opportunity of improving their skills speaking another language. Therefore, the scholars at the high level of educational systems have to rethink their traditional approaches in terms of teaching methodologies in order to be able to integrate these students, that every academic year are coming from abroad. Portugal is not an exception on this matter, neither the scientific domain of spatial planning. Actually, during the last years, the number of foreign students choosing to study in this country is rapidly increasing. Even though some years ago, most of the international students were originated from Portuguese speaking countries, comprising its former colonies such as Brazil, Angola, Cape Verde or Mozambique, recently the number of students from other countries is increasing, including from Syria. Characterized by a mild climate, a beautiful seashore and cities packed with historical and cultural interests, this country is a very attractive destination for international students. In this sense, this study explores the beliefs about teaching methodologies that scholars in spatial planning domain can use to guide their practice within Architecture degree, in order to promote de integration of international students. These methodologies are based on the notion that effective teaching is student-centred rather than teacher-centred, in order to achieve a knowledge-centred learning environment framework in terms of spatial planning skills. Thus, this article arises out of a spatial planning unit experience in the Master Degree in Architecture (MIA) course, at the University of Beira Interior (UBI) in Portugal, to understand more about teaching methodologies, in order to promote the integration of international students. The study explores the teamwork tasks and the hetero-evaluation as new approaches in the teaching methodologies focused on the student-centred teaching. This research main conclusion is the need of promoting a shift from lecture-based and teacher-centred practices to student-centred approach.
- Application of GIS-based multi-criteria analysis for site selection of aquifer recharge with reclaimed waterPublication . Pedrero, Francisco; Albuquerque, Antonio; Monte, Helena Marecos do; Cavaleiro, Victor; Alarcon, Juan JoseReclaimed water from small wastewater treatment facilities in the rural areas of the Beira Interior region (Portugal) may constitute an alternative water source for aquifer recharge. A 21-month monitoring period in a constructed wetland treatment system has shown that 21,500 m3 year−1 of treated wastewater (reclaimed water) could be used for aquifer recharge. A GIS-based multi-criteria analysis was performed, combining ten thematic maps and economic, environmental and technical criteria, in order to produce a suitability map for the location of sites for reclaimed water infiltration. The areas chosen for aquifer recharge with infiltration basins are mainly composed of anthrosol with more than 1 m deep and fine sand texture, which allows an average infiltration velocity of up to 1 m d−1. These characteristics will provide a final polishing treatment of the reclaimed water after infiltration (soil aquifer treatment (SAT)), suitable for the removal of the residual load (trace organics, nutrients, heavy metals and pathogens). The risk of groundwater contamination is low since the water table in the anthrosol areas ranges from 10 m to 50 m. On the other hand, these depths allow a guaranteed unsaturated area suitable for SAT. An area of 13,944 ha was selected for study, but only 1607 ha are suitable for reclaimed water infiltration. Approximately 1280 m2 were considered enough to set up 4 infiltration basins to work in flooding and drying cycles.
- Water Treatment Sludge as Geotechnical Liner Material: State-of-ArtPublication . Marchiori, Leonardo; Albuquerque, Antonio; Cavaleiro, VictorThe periodical cleaning of the decanters at the plant generates solid wastes called water treatment sludges (WTS), a chemical compound similar to aluminum silicates. WTS’s properties have been studied for geotechnical purpose and it seems to be suitable for producing liner materials for landfills, dams, ponds, and lagoons which store and prevent soil’s infiltration of residues. Liners are usually shaped of soil and geosynthetics, their main properties required are compaction, compressibility and shear strength, chemical compatibility, and hydraulic conductivity. WTS to be considered as a soil substitute, it must be function like a soil, thus, for developing alternative materials, physical, chemical, mechanical, and hydraulic characterization laboratorial parameters are the first step to make viable its reuse. In this sense, the study aims to review the literature over the above-mentioned parameters in order to evaluate WTS as liner material. This review concluded that WTS have high heterogeneity in chemical and mechanical behavior due source of water and treatment processes. WTS’ water affinity affects plasticity behavior, and its incorporation into soils seems to contribute for a composite with pozzolanic characteristics, low specific gravity, finer granulometry, and mechanical stabilization. Although need attention on its chemical compatibility, the influence on shear resistance—increasing internal effective friction angle and decreasing cohesion—and the optimum ratio of introduction within soils for an alternative liner material. Nonetheless, there are lacks in literature over hydraulic conductivity, and long-term behavior, the use of the material in practice must be preceded by pilot tests or experimental landfills.
- New Methodology for Rocks’ Geomechanical Characterization with Schmidt SclerometerPublication . Cavaleiro, Victor; Marchiori, Leonardo; Morais, Maria Vitoria; Marchi Oliveira, Gabriel; Cocchiarale, MarcelaHardness is a parameter that gives information about the behavior of rocks when subjected to certain deformations. Various non-destructive tests are available for hardness quantification, the use of the Schmidt Sclerometer is the most used due its expedition, among existing sclerometers, the Schmidt rebound hammer, type N-34, with an impact energy equal to 2,207 N.m (0.225 Kgm) was selected for experimental tests. Schmidt's hardness index (R) obtained were related to other physical parameters of the rock, namely uniaxial compressive strength (UCS), elasticity modulus (Ɛ), specific gravity and granularity. For comparison purpose, several literature’s methodologies are present focused on improving procedures and developing correlations for different rock types. In this sense, to assess the methodology that best suits granitic rocks’ characterization, several laboratorial and “in situ” tests from the literature were performed. Additionally, the paper proposes a new methodology based on the analysis of the results and a good relation between R and UCS parameters, concluding reliability on the methodology for values of non-porphyroid granitic rocks, predominantly biotitic and from medium to fine granularity, in a precise and consistent way.
- Geotechnical Characterization of Water Treatment Sludge for Liner Material Production and Soft Soil ReinforcementPublication . Marchiori, Leonardo; Studart, André; Albuquerque, Antonio; Cavaleiro, Victor; Silva, AbilioA water treatment sludge (WTS) was characterized in order to evaluate if its properties would be suitable for use as liner of earthworks or for strengthening a clay soil. A WTS and a clayey soil was characterized in terms of granulometry, cumulative volumes, specific surface, density, plastic limit, liquid limit, water content, hydraulic conductivity, and characteristics of compaction (optimal water content and dry density). This study aimed to exhibit and evaluate these investigated parameters of WTS, soft soil and mixed proportions between the materials for liners’ material production while evaluating soft soils’ reinforcement feasibility. The results have shown WTS’s contribution with its fine granulometry and compaction characteristics, indicating filling properties and possible feasibility as soft soils additions for liners’ material production while being applicable for soils‘ reinforcements, corroborating with existing literature on the subject. Thus, the currently developed investigation has exposed WTS as a potential addition for these applications while also attending society’s new demands towards a more sustainable future.
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