Sivaldo Leite Correia

Centro Universitário - Católica de Santa Catarina, Joinville, Santa Catarina, Brazil

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Publications (33)28.16 Total impact

  • A. Schackow · D. Stringari · L. Senff · S.L. Correia · A.M. Segadães
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    ABSTRACT: The use of metakaolin is known to help improve properties of Portland cement-based mortars. The presumed similarities between the characteristics of metakaolin and those of a powdered (<45 μm) fired clay brick clean waste (CBW) led to the investigation of the effect on the durability of mortars of partial replacement (10, 25 and 40 wt.%) of Portland cement by CBW. Properties such as 28 and 90 days-compressive strength, water absorption, apparent porosity, absorption by capillarity, chloride retention, carbonation depth and sulphate resistance were evaluated. The CBW-containing cured mortars showed improved strength and density, as the result of combined physical and pozzolanic pore filling effect of added CBW. However, CBW-free mortar exhibited larger spreading and, being more porous, higher sulphate resistance and ability to absorb chlorides. Optimum performance was found for the 40 wt.% CBW mortar whose compressive strength can be up to 130% higher than that of the CBW-free mortar.
    No preview · Article · Jun 2015 · Cement and Concrete Composites
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    ABSTRACT: This paper shows the first results of a prototype for image computer analysis applied on micrographs obtained by scanning electron microscope (SEM) based on backscattered electrons. Physical essays were done on concrete samples containing particulate tailings bricks (clay bricks waste powder – CBW) for characterization as to compressive strength and microstructure. Micrographs were captured from various points of each sample and subjected to image computational analysis for estimating micro-structural characteristics associated with resistance of concrete. The physical essays results were compared to the data from computer analysis. The proposal shown to be promising for the characterization of concrete containing CBW.
    No preview · Article · Jan 2014
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    ABSTRACT: A fresh green sand, spent green sand, and a weathered spent green sand (wSGS) from a foundry landfill were analyzed using diffractometry, electron microscopy, fluorometry, granulometry, spectrometry, and thermogravimetry (TG). Our objective was to understand how the physicochemical properties of the foundry green sands change from their original form after being subjected to the casting process, then after weathering at the landfill. A quantitative phase composition model was also postulated for each material based on the TG results and it was found to be the most reliable and informative quantitative data for this type of residue. The weathered sample, that remained in a landfill for two years, was found to be composed of almost pure sand. Because of the weathering process, it may be possible to use the wSGS as a virgin sand replacement in the regeneration system or in geotechnical applications where bentonite would affect the properties of the final product.
    Full-text · Article · Sep 2012 · Thermochimica Acta
  • Sivaldo L. Correia · Denilso Palaoro · André Mautone · Ana M. Segadães
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    ABSTRACT: In industrial practice involving mixtures of raw materials, it is desirable to be able to predict how a change in their proportions will affect the product's properties. In this work the effect of three major vulcanized rubber raw materials was investigated. All other raw materials, as well as processing conditions, were kept constant. Ten formulations were vulcanized by compression moulding (175 °C, ∼17 MPa, during 5 minutes) and characterized. The statistically valid property equations calculated from the characterization results show that a range of compositions exists within which the final product has the desired properties and can still be comfortably manufactured.
    No preview · Article · Sep 2012 · Macromolecular Symposia
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    Adilson Schackow · Sivaldo Leite Correia · William E. Lee
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    ABSTRACT: An integrated optimisation methodology has been used to optimise the material cost as well as the fresh and hardened properties of concretes containing fired clay brick waste (CBW) as an active replacement for Portland cement. It reveals that it is possible to produce low cost concrete mixtures containing fired CBW as a partial replacement for Portland cement up to 30 %, aggregate-to-cement ratio of 2.36 and a limited water-to-cement ratio of 0.44 to 0.49 (weight). SEM backscattered electron image and EDX microanalysis examinations on fractured surface sample reveal complex microstructure which is result of the products of the hydration reaction, containing C-S-H gel, hydrated and partially hydrated materials.
    Full-text · Conference Paper · Jun 2011
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    Adilson Schackow · Sivaldo Leite Correia · William E. Lee
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    ABSTRACT: A statistical approach has been used to model physical properties of concretes containing fired clay brick waste (CBW) as an active replacement for Portland cement. The results show that the 7-day (15 to 25 MPa) and 28-day (24 to 35 MPa) compressive strength remained within the typically-specified ranges, demonstrating the suitability of the use of CBW in concrete applications. In addition, workability of the waste-containing concretes was adequate for application in the construction industry. SEM backscattered electron image and EDX microanalysis examinations on fractured surface sample reveal the complex microstructure and morphology of the reacted and partially reacted phases in the concrete mixture containing fired clay brick waste.
    Full-text · Conference Paper · Jun 2011
  • S. L. Correia · D. Hotza · A. M. Segadães

    No preview · Article · Feb 2011
  • Sivaldo L. Correia · Tânia Partala · Felipe C. Loch · A.M. Segadães
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    ABSTRACT: This paper presents results from an investigation on the potential use of waste vulcanized rubber scrap (WRS) particles as aggregate in construction mortars. The investigation was carried out using a 32 factorial design of experiments and the response surface methodology. Mortar mixtures were prepared using WRS as fine aggregate (10, 20 and 30 vol.%) with water/cement ratios of 0.52, 0.55 and 0.60. Fresh mortar consistency index and hardened mortar 28-day compressive strength were evaluated. The influence of the WRS content on the physical and mechanical properties was established, and the suitability of WRS use in a mortar application was demonstrated.
    No preview · Article · Aug 2010 · Composite Structures
  • S.L. Correia · F.L. Souza · G Dienstmann · A.M. Segadães
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    ABSTRACT: Recycling of industrial wastes and by-products can help reduce the cost of waste treatment prior to disposal and eventually preserve natural resources and energy. To assess the recycling potential of a given waste, it is important to select a tool capable of giving clear indications either way, with the least time and work consumption, as is the case of modelling the system properties using the results obtained from statistical design of experiments. In this work, the aggregate reclaimed from the mud that results from washout and cleaning operations of fresh concrete mixer trucks (fresh concrete waste, FCW) was recycled into new concrete with various water/cement ratios, as replacement of natural fine aggregates. A 3(2) factorial design of experiments was used to model fresh concrete consistency index and hardened concrete water absorption and 7- and 28-day compressive strength, as functions of FCW content and water/cement ratio, and the resulting regression equations and contour plots were validated with confirmation experiments. The results showed that the fresh concrete workability worsened with the increase in FCW content but the water absorption (5-10 wt.%), 7-day compressive strength (26-36 MPa) and 28-day compressive strength (32-44 MPa) remained within the specified ranges, thus demonstrating that the aggregate reclaimed from FCW can be recycled into new concrete mixtures with lower natural aggregate content.
    No preview · Article · Aug 2009 · Waste Management
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    ABSTRACT: The ceramics industry, given the high volume of materials processed, stands as one of the largest consumers of natural raw materials but has also the capacity and potential to make significant contributions to solving environmental problems associated with other industries rejects. This work investigates the effects of quartz sand replacement by agate rejects (scrap) in a traditional triaxial porcelain composition. The study was carried out using the design of experiments (DoE) method. Characterization results were used to calculate statistically significant and valid regression equations, relating dried and fired body properties with clay, feldspar and agate scrap contents in the unfired mixture. The regression models were then discussed against X-ray diffraction and scanning electron microscopy results and used simultaneously to delimit the combinations of those three raw materials most adequate to produce a porcelainized stoneware floor tile with specified properties. Thus, an alternative use of an otherwise waste material is proposed, which can be translated into economic benefits and an important and welcome relief on environmental and waste disposal concerns.
    No preview · Article · Aug 2008 · Journal of Hazardous Materials
  • S. L. Correia · C. M. Gomes · D. Hotza · A. M. Segadães
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    ABSTRACT: The simultaneous effect of raw materials type and content on physical and technological properties of a triaxial ceramics system has been studied in the range of values used in industrial practice. The investigation has been carried out using the statistical design of mixture experiments, a special case in response surface methodologies. Ten formulations of the three raw materials selected were used in the experimental design. Those formulations were processed under conditions similar to those found in the ceramics industry: powder preparation (wet grinding, drying, granulation and humidification), green body preparation (pressing and drying) and firing. A non-linear programming approach was applied to minimize the cost of the three-component ceramics, considering optimum ranges of bulk density, bending strength, water absorption and porosity of sintered bodies. A validation experiment was performed to confirm the optimized composition predicted.
    No preview · Chapter · Mar 2008
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    ABSTRACT: This paper presents some of the results of an investigation on the possible applications of use of waste concrete aggregates from mixer trucks concrete productions (WCA) in concrete. The investigation has been carried out using factorial design for experimental design. For the study, the physical and mechanical properties along their durability of concrete produced with WCA were investigated and the results presented. Concrete mixtures were prepared using WCA as the replacement of natural fine aggregate at the level 10%, 20% and 30 wt.% with water/cement ratios of 0.40, 0.50 and 0.60. Properties of fresh and hardened concrete were evaluated: fresh unit weight, consistency, 7-day and 28-day compressive strength were carried out in specimens. The necessary data for establishing a mix proportion design and a quality control method are obtained using a full factorial design 32. The influence of level of WCA on the mineralogical composition has been established, and its suitability for use in a concrete application has been assessed. Empirical contour plots for the physical-mechanical properties of fresh and hardened concrete with WCA were obtained via regression analysis, which predict that as the amount of waste increases, has no or little effect on the compressive strength of concrete mixes. The results form confirmation experiments justify the prediction from the statistical approach.
    Full-text · Article · Jan 2008 · Materials Science Forum
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    ABSTRACT: In the present study, the waste scrap agate, obtained as a by-product of rock agate beneficiation as decorating ends and media for wet grinding was used as inert filler in a traditional triaxial red stoneware tiles composition. The effects on the technological properties have been investigated. The study has been carried out using the mixtures experiments method for the experimental design. Characterization results were used to calculate statistically significant and valid regression equations, relating dried and fired body properties with clay, feldspar and scrap agate contents in the unfired mixture. The regression models were then used simultaneously to delimit the combinations of those three raw materials most adequate to produce a ceramic body with specified properties. The use of mathematical optimisation shown that, for the particular raw materials under consideration, there is a rather forgiving composition range of clay (20-68 wt.%), feldspar (17-50 wt.%) and scrap agate (15-45 wt.%) contents within which it is possible to simultaneously specify the technological requirements for triaxial red stoneware tiles bodies, not only of the fired products but also of the intermediate materials at important stages of the processing.
    Full-text · Article · Jan 2008 · Materials Science Forum
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    Sivaldo L. Correia · Dachamir Hotza · Ana M. Segadães
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    ABSTRACT: This work describes the relationships observed between the porosity of fired ceramic test pieces and the raw materials contents in the unfired mixture. The investigation was carried out using the mixture experiments design approach coupled with response surface methodology, which enables the calculation of statistically significant models for the properties from a limited number of experimental results. Ten formulations of a clay mixture, potash feldspar and quartz sand were processed in the laboratory under fixed conditions, similar to those used on wall and floor tile industrial practice, and characterized. Closed porosity (CP) was estimated from the analysis of back-scattered SEM photomicrographs, open porosity (OP) was calculated as the product of bulk density and water absorption, and total porosity (TP) was calculated from OP and CP values. Characterization results were used to calculate statistically significant and valid regression equations, relating those properties with the raw material contents in the unfired mixture. For the particular raw materials and processing conditions used, the models clearly show how quartz contributes to increasing OP and the crucial role played by feldspar when CP and TP are to be minimized (circa 3 vol.%), and how the clay content can counteract that effect and lead to maximum closed porosity (∼14 vol.%).
    Full-text · Article · Dec 2007 · Journal of Materials Science
  • S.L. Correia · G. Dienstmann · M.V. Folgueras · D. Hotza
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    ABSTRACT: The effects of using scrap agate as filler in triaxial porcelain bodies through mixture design and response surface analysis were investigated. Linear firing shrinkage (LFS) was calculated from the change in length upon firing of the flat test pieces. The fired modulus of rupture (MOR) of fired test pieces was determined in three-point bending tests at 1 mm/min crosshead speed until rupture using test bars. Water absorption (WA) was determined using the Archimedes liquid-displacement method by immersion in boiling water for 2 h using a digital analytical scale with a resolution of 1 mg. Results of the variance analysis of the regressions obtained for LFS, MOR, WA determined the effect of raw material on these properties. It was found that increased scrap-agate content increased WA and increased fieldspar content decreased WA. The use of intersecting surfaces showed that there was a suitable composition range of clay, fieldspar, and scrap agate contents for particular raw materials, within which it was possible to simultaneously specify the values of various technological properties.
    No preview · Article · Feb 2007 · American Ceramic Society Bulletin
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    ABSTRACT: The simultaneous effect of raw materials (A, B and C) on physical and technological properties of brick compositions was studied. This investigation was carried out using the statistical design of mixture experiments. Ten mixtures of three raw materials were selected and used in the experiments design. Those mixtures were processed under conditions similar to those found in the ceramics industry. Fired body characterisation results were then used to iteratively calculate statistically significant and valid regression equations (trace plots), relating linear firing shrinkage, open porosity, fired bending strength and water absorption with the proportions of raw materials. The microstructures of some selected samples were studied using scanning electron microscopy. Mixtures with high clay B contents were most adequate to produce, under constant processing conditions, a brick with specified properties. The microstructures are characterized by a low closed porosity and absence of vitreous phase.
    No preview · Article · Nov 2006 · Materials Science Forum
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    S. L. Correia · A. P. N. Oliveira · D. Hotza · A. M. Segadães
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    ABSTRACT: The effect of raw materials type and content on the properties of clay–feldspar–quartz compositions was studied using the statistical design of mixture experiments. Based on wall and floor tile industrial practice, 10 mixtures of three raw materials were selected and processed. Characterization results were used to calculate statistically significant and valid regression equations, relating fired body properties with clay, feldspar, and quartz contents in the unfired mixture. Such statistical modeling is discussed against quantitative X-ray diffraction and scanning electron microscopy results. The glassy phase present was found to control the microstructure and the mechanical strength of the fired ceramic body.
    Full-text · Article · Aug 2006 · Journal of the American Ceramic Society
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    ABSTRACT: Mixtures of clays are often used in the manufacture of bricks. In industrial practice, it is desirable to be able to predict, in an expeditious way, what the effects of a change in raw materials or the proportions thereof might be in the various processing steps towards the final product. When the property of interest is basically determined by the combination of raw materials, an optimisation methodology specific to the design of mixture experiments can be successfully used. In the present study, fired bending strength and linear firing shrinkage were selected as the properties to model. Ten formulations of three different clays were selected and used in the experiments design. Those formulations were wet processed, uniaxially pressed, and then fired at 1000 °C for 2 h. From the experimental results, regression models were calculated, relating each technological property with the proportions of raw materials. The regression models were then used simultaneously to define which combination of those three raw materials was most adequate to produce, under constant processing conditions, a brick with specified properties.
    No preview · Article · Jan 2006 · Materials Science Forum
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    S. L. Correia · D. Hotza · A. M. Segadães

    Full-text · Article · Sep 2005 · Cerâmica
  • S.L. Correia · D. Hotza · A.M. Segadães
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    ABSTRACT: In the development and manufacture stages of ceramic floor and wall tiles, bending strength of dried and fired bodies, linear firing shrinkage and water absorption are basically determined by the combination of raw materials and frequently used as process and quality control parameters. Thus, the techniques of experiments design can be used to model those properties of such ceramics bodies. In the present study, ten formulations of three selected raw materials, namely a clay mixture, potash feldspar and quartz, were processed under conditions similar to those used in the ceramics industry: powder preparation (wet grinding, drying, granulation and humidification), green body preparation (pressing and drying), firing (at 1170 °C) and characterization. With the experimental results, regression models were calculated, relating each technological property with the proportions of raw materials. After statistical analysis and verification experiments, the significance and validity of the models were confirmed. The regression models were then used simultaneously to delimit the combinations of those three raw materials most adequate to produce, under constant processing conditions, a ceramic body with specified properties.
    No preview · Article · Jan 2005

Publication Stats

178 Citations
28.16 Total Impact Points

Institutions

  • 2006-2015
    • Centro Universitário - Católica de Santa Catarina
      Joinville, Santa Catarina, Brazil
  • 2005-2012
    • Universidade do Estado de Santa Catarina
      Joinville, Santa Catarina, Brazil
  • 2004-2008
    • Federal University of Santa Catarina
      • Departamento de Engenharia Química e Engenharia de Alimentos
      Nossa Senhora do Destêrro, Santa Catarina, Brazil