Navegando por Autor "SANJAD, Thais Alessandra Bastos Caminha"

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Caracterização mineralógica de azulejos de Salvador e Belém dos séculos XVI, XVII e XIX
(2004-12) SANJAD, Thais Alessandra Bastos Caminha; ANGÉLICA, Rômulo Simões; OLIVEIRA, Mário Mendonça de; COSTA, Walmeire Alves de Melo
The present article is a study about the mineralogical composition of ancient tiles from centuries XVI, XVII and XIX, found in Belém and Salvador, in order to interpret the possible raw material and burning temperature. Quartz was identified in all samples. Other crystalline phases found are mullite, cristobalite, calcite, anorthite, hematite, gehlenite, diopside and wollastonite. Based on the probable raw material and probable burning temperature it was possible to organize the samples into three groups: group 1 - kaolinite and quartz, T between 1200º and 1728º C; group 2 - kaolinite, calcite and/or dolomite and iron oxide or hydroxide, T between 900º e 1200ºC; group 3 - quartz, clay minerals (probably kaolinite), calcite and/or dolomite, iron oxide or hydroxide, and T between 1200º e 1565º C.
Acesso aberto (Open Access)
Eflorescência salina na igreja de Santo Alexandre, Belém - PA
(Universidade Federal do Pará, 2015-09) LOUREIRO, Alexandre Máximo Silva; ANGÉLICA, Rômulo Simões; SANJAD, Thais Alessandra Bastos Caminha; OLIVEIRA, Mário Mendonça de; COSTA, Marcondes Lima da
The structural masonry of the historical monuments of the city of Belém, Brazil, is made of stones and solid bricks fixed with lime mortar, which is affected by different pathologies, including salt efflorescence and moisture action. Some authors explain that these two agents cause layer detachment, mortar pulverization, cracks and a whitened appearance. This aim of this study was to identify the degradation process affecting the masonry of the right transept of the Church of Santo Alexandre, using instrumental analytical techniques. Laboratory analyses were used in order to understand the saline efflorescence process, the material damage it causes and the main kinds of salts. The first step in the study was to map out the masonry and the damage, showing the current situation and the most damaged areas. That was followed by a physical characterisation through an analysis of mortar particle sizes and proportions, analysis of masonry moisture contents, chemical characterisation -qualitative and quantitative chemical analysis of soluble salts, and mineralogical characterisation by X-ray diffraction. The techniques applied were effective and contributed to the achievement of a correct diagnosis, guiding the type of interventions required to solve the problem.
Acesso aberto (Open Access)
Intemperismo tropical em fachadas azulejadas de edificacoes historicas em belem do para
(Universidade Federal do Pará, 2007-05-14) SANJAD, Thais Alessandra Bastos Caminha; COSTA, Marcondes Lima da; http://lattes.cnpq.br/1639498384851302
The application of European tiles on building façades of Belém city started since 19th century. After hundred years under weathering action, the tiles started to show alterations. To understand these weathering action two historical buildings of the 19th century were studied: Palacete Pinho and Solar do Barão de Guajará, located on Belém old town. The Palacete building has German tiles (PPA and PPA-C) and Portuguese tiles from Porto city (PPP). The Solar building has only Portuguese tiles on its main façade, from Porto city (BGFP). Dark stains are the main kind of alteration found in the German tiles. They are located between the glaze and the ceramic part, without lost of glaze. In case of the Portuguese tiles from both buildings, the lost of glaze is frequent, besides the presence of green stains under the detached glaze. Physical characterization results are as follow: 1) the German tiles (PPA and PPA-C) have a lower accessible porosity (12.96% and 9.59%, respectively) and higher density (1.99 g/cm3 and 1.92g/cm3, respectively), than the Portuguese ones (PPP: 29.34% and 1.59 g/cm3 and BGFP: 17.53% and 1.74 g/cm3); 2) the Portuguese tiles present glaze thickness between 0.06-0.1 mm (PPP) and 0.5-0.54 (BGFP) and the German ones between 0.04-0.2 mm (PPA and PPA-C); 3) Portuguese glazes exhibit an abrupt contact with the ceramic part while German tiles show a transition zone between these two layers. Mineralogical analyses of the ceramic parts were carried out using XRD and SEM/EDS. The main mineral phases identified are: quartz, mullite, and cristobalite (German tiles) and quartz, gehlenite, diopside and calcite (Portuguese tiles). Quartz, cassiterite and apatite were also found in both German and Portuguese glazes; only the PPP sample does not have cassiterite. Total chemical analyses of the ceramic parts of German tiles indicated a major amount of SiO2 (75%) and Al2O3 (18%). In the Portuguese tiles, besides SiO2 (46%) and Al2O3 (15%), there is also high CaO contents (22%). Concerning the glazes, the chemical composition is mainly composed by Si and Pb. The green and dark stains beneath the glaze are related to microorganisms of the Cyanophyta and Bacillariophyta divisions. Climatic data records from Belém city were recovered since 1898 and showed that no significant climate changes happened in the region. Rain water sampling and analysis were also carried out in the vicinities of the two studied buildings. 11 The results show small Ca concentrations above regular levels for rain water, which can be related to the mortars. The temperature measurements on tile surfaces indicate variations for different parts of the façades. In the Solar Building, areas of high surface temperature are those where the glaze was unattached to the ceramic bodies. The results showed that the tiles are rather resistance to the tropical weathering. German tiles have a minor glaze lost because of the interface zone between glaze and ceramic part. The absence of such zone in the Portuguese tiles turn then more prone to weathering due to climate changes, mainly thermal daily variations, which lead to glaze detachment.
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.
Acesso aberto (Open Access)
The mineralogy and chemistry of the German and Portuguese tiles used to face a historic building in the Amazon region and their natural susceptibility to tropical weathering
(Instituto Nacional de Pesquisas da Amazônia, 2013-09) COSTA, Marcondes Lima da; SANJAD, Thais Alessandra Bastos Caminha; PAIVA, Rosildo Santos
During the 19th century, the most prominent buildings of the city of Belém were faced entirely with tiles manufactured in Portugal and Germany, which now exhibit distinct degrees of degradation. The Pinho mansion is one of the most important of these buildings and was selected for the investigation of the action of the tropical Amazonian climate on the degradation of the tiles. To achieve this objective, the tiles were mapped for organic and inorganic degradation, and samples were collected for analysis. The minerals were determined by XRD, the chemical composition by classical wet methods and SEM/EDS, and the microorganisms under the microscope. The results show that the German and Portuguese tiles are quite different in their composition. While both ceramic bodies are composed of SiO2 and Al2O3, CaO was found only in the Portuguese tile. The low Na2O and K2O contents indicate the addition of materials to reduce the fusion temperature. SiO2 and PbO are the main constituents of the glaze, with CoO and FeO being added as pigment. The ceramic body of the German tiles is constituted of quartz, mullite, and cristobalite, in contrast with the Portuguese tiles, which are made of quartz, gehlenite, diopside, calcite, and feldspars. The glazes are XRD-amorphous. The chemical and mineralogical differences between the German and Portuguese tiles indicate that they were produced from different raw materials under distinct thermal processes. The most prominent weathering-related modifications are the thin layers (German tiles), oxidation stains, dark stains, the detachment of the tile (Portuguese tiles), loss of the glaze and powdering of the ceramic body (Portuguese tiles) through the establishment of Cyanophyta and Bacillariophyta.. The distinct degradation patterns of the tiles exposed to the tropical Amazon climate are a consequence of their distinct mineralogy and chemistry.
Acesso aberto (Open Access)
Ornamentos de platibanda em edificações de Belém entre os séculos XIX e XX: inventário e conservação
(Universidade Federal do Pará, 2017-12) ARRUDA, Tainá Chermont; SANJAD, Thais Alessandra Bastos Caminha
The vitrified ceramic ornaments were used as decorative elements and pieces such as statues, had allegorical paper in the crowning of the facades to highlight or to characterize the typological function of the building or as a symbol that the owner wanted to convey referring to the values defended at the time of the Industrial Revolution. The ornaments on the platibands formed a set of pieces with allegorical meanings, which symbolized wealth and erudition, to be attributed to the elite, since the Modern era. The objective of this research was to identify the ornaments made of glazed ceramic that make up the eclectic architecture of the Historic Center of Belém (Pará) and its surroundings with a view to tracing subsidies for its preservation. We sought to identify and locate the types of vitrified ornaments existing in the Historic Center and its surroundings of the city of Belém do Pará, through a visual inspection of the region, making it possible to analyze and understand the context of these pieces in the local reality. A total of 225 properties with ornamental plaice were identified in the analyzed area. The use of textual documents, printed catalogs, newspapers and albums of the 19th and 20th century was used to support research and identification of ornaments. Vitrified ceramic ornaments suffer an accelerated process of disappearance because they are exposed in the building panels, since they are more vulnerable to intemperate action, be it physical, chemical or mineralogical, and anthropic action, including acts of vandalism. These glazed ceramic ornaments are important examples of the cultural heritage of Belém, as they are evidence of the European influence in the region, more specifically Portuguese, besides being products of technical development of the material and symbolic of the nineteenth century, which deserve urgent preservation actions.