Artigos Científicos - ITEC

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/3360

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Agora exibindo 1 - 6 de 6

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Aforar, arrumar e alinhar: a atuação da Câmara Municipal de Belém na configuração urbano-fundiária da cidade durante o século XIX
(Universidade Federal do Pará, 2018-12-03) LIMA, José Júlio Ferreira; FISCHER, Luly Rodrigues da Cunha; ABREU, Paula Vanessa Luz de
The paper examines the morphological transformation of the city of Belém, influenced by the new land regime inaugurated by the Land Law of 1850 and by the growth of state urban planning. We investigate the actions of the City Council in the urban land tenure and the implementation of an Expansion Plan for Belém in the 19th century. In order to understand the spatial actions undertaken by the City Council, we started from the study of three instruments: emphyteusis, the main form of land transfer used by the City Council; alignment, related to the public-private boundaries and streets definitions; and land demarcation. We investigated the original land documents that record the emphyteusis, alignment and land demarcation carried out by the City Council along the Bragança Road, the main axis of city expansion in the 19th century. From the graphic spatialization of the information contained in these documents and the research in local newspapers, it was possible to verify that the City Council acted as a pioneer state agent, through a systematized land subdivision project. The discussion contributes to the comprehension of the structuring role of the local power in the definition and change of urban morphology and to a new understanding of the Belém Expansion Plan, classifying it as not only a urban beautification project, but as a product of the political-land tenure transition that marks the nineteenth century.
Acesso aberto (Open Access)
Avaliação do comportamento reológica e mecânico de geopolímero sintetizado com reaproveitamento de resíduo
(Rede Latino-Americana de Materiais, 2018-10) BRITO, Woshington da Silva; BRUM, Sebastião Martins; SILVA, André Luis Mileo Ferraioli; FELIPE, Augusta Maria Paulain Ferreira; SOUZA, José Antônio da Silva
The sustainable construction of the future, besides low energy consumption and greenhouse gas emissions must also adopt the principle of reusing wastes generated by the production chain that impact the environment. One of the most impacting wastes generated by the aluminum production chain is fly ash. Geopolymers are cementitious materials with a three-dimensional structure formed by chemical activation of aluminosilicates. According to studies some ashes have proven to be suitable sources of Al and Si for the geopolymerization reaction. One of the most important aspects in the commercializing these products is their behavior in a plastic state. The workability of fresh geopolymer paste can be measured using several common tests used for Portland cement concrete, such as flow and slump; however, a more in-depth characterization of their rheology is essential for understanding their basic setting mechanisms. The objective of this work was to evaluate the rheological behavior of the Davidovits (SiO2/Al2O3) geopolymer paste at 2.65; 3.04 and 4.11. The mechanical resistance to compression at 24 hours, 7 days and 28 days of geopolymer cure was also evaluated. The geopolymerization reaction was conducted at ambient temperature of 28°C and 15 Molar sodium hydroxide (NaOH) and 10 Molar sodium silicate (Na2SiO3), were used as the activator. Fly ash and metakaolin were used as source of Al and Si was used. XRD, XRF, SEM techniques were used in the characterization of raw materials and geopolymers. The geopolymer with a lower Davidovits ratio of 2.65 presented better workability in its fresh state and higher mechanical strength at 40.80 MPa compression with 28 days cure at ambient temperature. The Herchel Bulkley rheological model was the one that was best adjusted to the geopolymers.
Acesso aberto (Open Access)
Canaã dos Carajás: um laboratório sobre as circunstâncias da urbanização, na periferia global e no alvorecer do século XXI
(Associação Nacional de Pós-Graduação e Pesquisa em Planejamento Urbano e Regional, 2018-04) CARDOSO, Ana Cláudia Duarte; CÂNDIDO, Lucas Souto; MELO, Ana Carolina Campos de
This article addresses the processes of urbanization and urban sprawl in Canaã dos Carajás, a small relatively recent Amazonian municipality. The analysis is dialectically structured according to Lefebvre’s interpretation of the levels of social reality. The global level captures how capitalintensive activities (mining, ranching, and monoculture) have impacted the connection between the place of production and the global market. The mixed level explains how local social groups, inspired by global processes, have mediated urbanization. The local level demonstrates how blind spots in understanding the ongoing processes have impaired the strengthening of diversity, and led to the exclusion of social groups that most depend on the land and nature. We conclude that it is necessary to articulate contemporary formulations and studies on Brazilian urbanization so as to demonstrate the selective manner in which modernization takes place and is constituted in new forms of colonization, whenever economic opportunities formulate socioenvironmental issues in a conservative manner.
Acesso aberto (Open Access)
Construction delays: a case study in the Brazilian Amazon
(Universidade Federal do Pará, 2017-09) MAUÉS, Luiz Mauricio Furtado; SANTANA, Wylliam Bessa; SANTOS, Paulo Cerqueira dos; NEVES, Renato Martins das; DUARTE, André Augusto Azevedo Montenegro
The construction industry is one of the industrial sectors with the lowest rates of fulfilment of contract deadlines, especially in developing countries. This fact has been the focus of considerable discussions seeking to identify the causes of the delays. The main purpose of this paper is to use factor analysis to identify the factors that are correlated with delay, contemplating exclusively residential real estate projects and using a city in the Brazilian Amazon as a case study. Based on the database from the government agency that authorises constructions in the city of Belém (City Planning Department - Secretaria Municipal de Urbanismo, SEURB) and data from construction companies, the study investigated 274 construction projects from the past 11 years. Factor analysis and work with the variables that can be identified and measured in the initial phase of the project, i.e., during the feasibility study, demonstrate that the physical characteristics of the apartments and the construction project are the primary causes for variations in construction delays; these causes have not yet been reported in the literature. We hope that the results of this study will contribute to more consistent forecasting of construction time, minimising the risk of delays.
Acesso aberto (Open Access)
Corrosão em estacas metálicas de torres de energia elétrica
(Rede Latino-Americana de Materiais, 2019-05) VILHENA, Alexandre Evangelista Rodrigues; PINTO, Renata Godinho; COSTA, Rafaela Reis da; PICANÇO, Marcelo de Souza; MACÊDO, Alcebíades Negrão
In order to maintain the quality and continuity of the power supply it is essential to monitor the integrity of the structure of the transmission towers usually executed in steel. This study evaluated soil corrosivity in the Amazon region in the Vila do Conde-Tucuruí stretch, state of Pará. The resistivity, potential soil structure, redox potential, pH, chloride, sulphate and sulfate concentration, besides the Steinrath index and the quantification of the soil corrosivity through the installation of test specimens in the studied soil. The data were collected in the dry and rainy period while the specimens were removed after 12 months of exposure. The soils of the region presented resistivity higher than 20 kΩ.cm, characterizing as few corrosives; the redox potential of 100 to 300 mV indicated mild to moderately corrosive soils; the potential soil structure remained in the range of -0.4 to -0.7 V/ECS being within the range considered normal; the Steinrath index classified the soils into little corrosive to non-corrosive and the corrosion rates of the test specimens indicated high corrosion at 3 meters depth. Based on the results of each evaluation method used it can be verified that the soil corrosivity increases with the depth, besides being favorable to the attack of microbiological corrosion.
Acesso aberto (Open Access)
Lime-based restoration paints: characterization and evaluation of formulations using a native species from the Amazon flora and PVA-based glue as additives
(Universidade Federal do Pará, 2017-09) SILVA, Mayra Martins; SANJAD, Thais Alessandra Bastos Caminha; COSTA, Marcondes Lima da; COSTA, Solange do Perpétuo Socorro Evangelista
Based on historic documents, two lime-based paint formulations were produced in laboratory in order to evaluate their basic characteristics as restoration materials for historic buildings with lime-based components. The paints were made basically with hydrated lime, clay, water and linseed (Linum usitatissimum L.) oil, and one formulation had PVA (polyvinyl acetate)-based glue as fixative, and the other one, Couma guianensis' latex. Each paint component was characterized by XRD and FTIR, and color and specular gloss measurements were performed on both paints. A preliminary assessment of the paints was conducted using the Pipe Method, the salt crystallization test, visual analysis for dustiness, and analysis of microbiological growth. The results showed that the laboratory-produced paints are theoretically and technologically compatible with lime-based coatings, however, their superficial performance can be improved to achieve greater durability. This study also brings to light local materials from the Amazon region that have great potential to be used and recognized as raw materials for paints and which could also be investigated for other uses.

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