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Jorgen Skibsted - One of the best experts on this subject based on the ideXlab platform.
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sulfate resistance of calcined clay limestone portland cements
Cement and Concrete Research, 2019Co-Authors: Zhenguo Shi, D Herfort, Sergio Ferreiro, Wolfgang Kunther, Josef Kaufmann, Barbara Lothenbach, Mette Rica Geiker, Jorgen SkibstedAbstract:Abstract Calcined clays emerge as a promising source of supplementary cementitious material, which can provide a significant lowering of the Portland clinker content in blended cements. This study focusses on sulfate resistance of calcined clay (CC) – limestone (L) – Portland cements for mortars exposed to a 0.11 M Na2SO4 solution at 5 and 20 °C after a hydration period of 91 days. The Pozzolanicity, compressive strength, pore structure, and sulfate resistance of mortars containing laboratory-made metakaolin or calcined montmorillonite and limestone have been investigated in cements with 35 wt% replacement of a white Portland or an ordinary Portland clinker. The results show that all mortars with CC/(CC + L) ≥ 0.5 exhibit excellent sulfate resistance. The consumption of portlandite by the pozzolanic reactions of the calcined clays and the dilution of the Portland clinker lead to a lower amount of calcium available for the secondary formation of gypsum and ettringite, which is identified as the main reason for the excellent sulfate resistance of the ternary blends. The results suggest that calcined clay – limestone – Portland cements are included in standards as a new type of sulfate-resisting Portland pozzolana cement and Portland composite cement.
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Sulfate resistance of calcined clay – Limestone – Portland cements
Cement and Concrete Research, 2019Co-Authors: Zhenguo Shi, D Herfort, Sergio Ferreiro, Wolfgang Kunther, Josef Kaufmann, Barbara Lothenbach, Mette Rica Geiker, Jorgen SkibstedAbstract:Calcined clays emerge as a promising source of supplementary cementitious material, which can provide a significant lowering of the Portland clinker content in blended cements. This study focusses on sulfate resistance of calcined clay (CC) – limestone (L) – Portland cements for mortars exposed to a 0.11 M Na 2 SO 4 solution at 5 and 20 °C after a hydration period of 91 days. The Pozzolanicity, compressive strength, pore structure, and sulfate resistance of mortars containing laboratory-made metakaolin or calcined montmorillonite and limestone have been investigated in cements with 35 wt% replacement of a white Portland or an ordinary Portland clinker. The results show that all mortars with CC/(CC + L) ≥ 0.5 exhibit excellent sulfate resistance. The consumption of portlandite by the pozzolanic reactions of the calcined clays and the dilution of the Portland clinker lead to a lower amount of calcium available for the secondary formation of gypsum and ettringite, which is identified as the main reason for the excellent sulfate resistance of the ternary blends. The results suggest that calcined clay – limestone – Portland cements are included in standards as a new type of sulfate-resisting Portland pozzolana cement and Portland composite cement.
Rossignolo, Joao Adriano - One of the best experts on this subject based on the ideXlab platform.
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Comparison of original and washed pure sugar cane bagasse ashes assupplementary cementing materials
'Elsevier BV', 2021Co-Authors: Pitolli Lyra Gabriela, Borrachero Rosado, María Victoria, Soriano Martinez Lourdes, Paya Bernabeu, Jorge Juan, Rossignolo, Joao AdrianoAbstract:[EN] The objective of this study was to evaluate the effects of potassium extraction on the Pozzolanicity of sugar cane bagasse ash (SCBA), with the aim of producing reactive ash for use in cementitious composites. The sugar cane bagasse ashes were produced at 600 °C for 60 min, with a heating rate of 4 °C/min. The ashes were then ground and washed for potassium extraction. In order to assess the ash behaviour before and after potassium extraction, the following procedures were performed: energy-dispersive spectroscopy (EDS), loss on ignition (LOI), particle size distribution, x-ray powder diffraction (XRD), x-ray diffraction in calcium hydroxide paste, analysis of lime fixation by thermogravimetry, and evaluation of pozzolanic reactivity analyses. Results show that the extraction of potassium, increases the concentration of silica causing a greater pozzolanic reactivity of the ashes.This study was financed in part by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior - Brasil (CAPES) - Finance Code 001.Pitolli Lyra, G.; Borrachero Rosado, MV.; Soriano Martinez, L.; Paya Bernabeu, JJ.; Rossignolo, JA. (2021). Comparison of original and washed pure sugar cane bagasse ashes assupplementary cementing materials. Construction and Building Materials. 272. https://doi.org/10.1016/j.conbuildmat.2020.122001S27
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A study of the chemical and physical properties of cashew nut shell ash for use in cement materials - 10.4025/actascitechnol.v32i4.7434
Universidade Estadual De Maringá, 2010Co-Authors: Lima, Sofia Araujo, Rossignolo, Joao AdrianoAbstract:As cinzas ocupam lugar de destaque dentre os resíduos agroindustriais por resultarem de processos de geração de energia. Sabe-se que muitas dessas cinzas possuem reatividade pozolânica, podendo ser utilizadas como adição mineral em matrizes de cimento Portland. O presente estudo tem como objetivo investigar as características físicas e químicas da cinza da casca da castanha de caju (CCCC), por meio dos seguintes ensaios: análise química, massa unitária, massa específica, extratos lixiviado e solubilizado, difratometria de raios X (DrX), superfície específica (BET) e análise da pozolanicidade com o cimento Portland e com a cal. O conjunto de análises deste trabalho indica a restrição ao uso da CCCC em matrizes cimentícias em função da baixa reatividade com o hidróxido de cálcio (CH) e dos altos teores de álcalis, dos metais pesados e do fenol detectados nessa cinza.Ash occupies a prominent place among agro-industrial wastes, as it is derived from energy generation processes. Several types of ash have pozzolanic reactivity, and might be used as replacement material for cement, resulting in less energy waste and lower cost. This work aimed to investigate the physical and chemical properties of the cashew nut shell ash (CNSA), by performing the following measurement tests: chemical analysis, bulk density, specific mass, leaching and solubilization process, X-ray diffraction (XrD), specific surface area (BET) and Pozzolanicity analysis with cement and lime. The results indicate a low reactivity of CNSA and the presence of heavy metals, alkalis and phenol
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A study of the chemical and physical properties of cashew nut shell ash for use in cement materials.
UNIV ESTADUAL MARINGA PRO-REITORIA PESQUISA POS-GRADUACAO, 2010Co-Authors: Lima, Sofia Araujo, Rossignolo, Joao AdrianoAbstract:A study of the chemical and physical properties of cashew nut shell ash for use in cement materials. Ash occupies a prominent place among agro-industrial wastes, as it is derived from energy generation processes. Several types of ash have pozzolanic reactivity, and might be used as replacement material for cement, resulting in less energy waste and lower cost. This work aimed to investigate the physical and chemical properties of the cashew nut shell ash (CNSA), by performing the following measurement tests: chemical analysis, bulk density, specific mass, leaching and solubilization process, X-ray diffraction (XrD), specific surface area (BET) and Pozzolanicity analysis with cement and lime. The results indicate a low reactivity of CNSA and the presence of heavy metals, alkalis and phenol
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Estudo das características químicas e físicas da cinza da casca da castanha de caju para uso em materiais cimentícios - 10.4025/actascitechnol.v32i4.7434
'Universidade Estadual de Maringa', 2010Co-Authors: Lima, Sofia Araujo, Rossignolo, Joao AdrianoAbstract:Ash occupies a prominent place among agro-industrial wastes, as it is derived from energy generation processes. Several types of ash have pozzolanic reactivity, and might be used as replacement material for cement, resulting in less energy waste and lower cost. This work aimed to investigate the physical and chemical properties of the cashew nut shell ash (CNSA), by performing the following measurement tests: chemical analysis, bulk density, specific mass, leaching and solubilization process, X-ray diffraction (XrD), specific surface area (BET) and Pozzolanicity analysis with cement and lime. The results indicate a low reactivity of CNSA and the presence of heavy metals, alkalis and phenol.As cinzas ocupam lugar de destaque dentre os resíduos agroindustriais por resultarem de processos de geração de energia. Sabe-se que muitas dessas cinzas possuem reatividade pozolânica, podendo ser utilizadas como adição mineral em matrizes de cimento Portland. O presente estudo tem como objetivo investigar as características físicas e químicas da cinza da casca da castanha de caju (CCCC), por meio dos seguintes ensaios: análise química, massa unitária, massa específica, extratos lixiviado e solubilizado, difratometria de raios X (DrX), superfície específica (BET) e análise da pozolanicidade com o cimento Portland e com a cal. O conjunto de análises deste trabalho indica a restrição ao uso da CCCC em matrizes cimentícias em função da baixa reatividade com o hidróxido de cálcio (CH) e dos altos teores de álcalis, dos metais pesados e do fenol detectados nessa cinza
Barbara Lothenbach - One of the best experts on this subject based on the ideXlab platform.
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sulfate resistance of calcined clay limestone portland cements
Cement and Concrete Research, 2019Co-Authors: Zhenguo Shi, D Herfort, Sergio Ferreiro, Wolfgang Kunther, Josef Kaufmann, Barbara Lothenbach, Mette Rica Geiker, Jorgen SkibstedAbstract:Abstract Calcined clays emerge as a promising source of supplementary cementitious material, which can provide a significant lowering of the Portland clinker content in blended cements. This study focusses on sulfate resistance of calcined clay (CC) – limestone (L) – Portland cements for mortars exposed to a 0.11 M Na2SO4 solution at 5 and 20 °C after a hydration period of 91 days. The Pozzolanicity, compressive strength, pore structure, and sulfate resistance of mortars containing laboratory-made metakaolin or calcined montmorillonite and limestone have been investigated in cements with 35 wt% replacement of a white Portland or an ordinary Portland clinker. The results show that all mortars with CC/(CC + L) ≥ 0.5 exhibit excellent sulfate resistance. The consumption of portlandite by the pozzolanic reactions of the calcined clays and the dilution of the Portland clinker lead to a lower amount of calcium available for the secondary formation of gypsum and ettringite, which is identified as the main reason for the excellent sulfate resistance of the ternary blends. The results suggest that calcined clay – limestone – Portland cements are included in standards as a new type of sulfate-resisting Portland pozzolana cement and Portland composite cement.
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Sulfate resistance of calcined clay – Limestone – Portland cements
Cement and Concrete Research, 2019Co-Authors: Zhenguo Shi, D Herfort, Sergio Ferreiro, Wolfgang Kunther, Josef Kaufmann, Barbara Lothenbach, Mette Rica Geiker, Jorgen SkibstedAbstract:Calcined clays emerge as a promising source of supplementary cementitious material, which can provide a significant lowering of the Portland clinker content in blended cements. This study focusses on sulfate resistance of calcined clay (CC) – limestone (L) – Portland cements for mortars exposed to a 0.11 M Na 2 SO 4 solution at 5 and 20 °C after a hydration period of 91 days. The Pozzolanicity, compressive strength, pore structure, and sulfate resistance of mortars containing laboratory-made metakaolin or calcined montmorillonite and limestone have been investigated in cements with 35 wt% replacement of a white Portland or an ordinary Portland clinker. The results show that all mortars with CC/(CC + L) ≥ 0.5 exhibit excellent sulfate resistance. The consumption of portlandite by the pozzolanic reactions of the calcined clays and the dilution of the Portland clinker lead to a lower amount of calcium available for the secondary formation of gypsum and ettringite, which is identified as the main reason for the excellent sulfate resistance of the ternary blends. The results suggest that calcined clay – limestone – Portland cements are included in standards as a new type of sulfate-resisting Portland pozzolana cement and Portland composite cement.
Zhenguo Shi - One of the best experts on this subject based on the ideXlab platform.
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sulfate resistance of calcined clay limestone portland cements
Cement and Concrete Research, 2019Co-Authors: Zhenguo Shi, D Herfort, Sergio Ferreiro, Wolfgang Kunther, Josef Kaufmann, Barbara Lothenbach, Mette Rica Geiker, Jorgen SkibstedAbstract:Abstract Calcined clays emerge as a promising source of supplementary cementitious material, which can provide a significant lowering of the Portland clinker content in blended cements. This study focusses on sulfate resistance of calcined clay (CC) – limestone (L) – Portland cements for mortars exposed to a 0.11 M Na2SO4 solution at 5 and 20 °C after a hydration period of 91 days. The Pozzolanicity, compressive strength, pore structure, and sulfate resistance of mortars containing laboratory-made metakaolin or calcined montmorillonite and limestone have been investigated in cements with 35 wt% replacement of a white Portland or an ordinary Portland clinker. The results show that all mortars with CC/(CC + L) ≥ 0.5 exhibit excellent sulfate resistance. The consumption of portlandite by the pozzolanic reactions of the calcined clays and the dilution of the Portland clinker lead to a lower amount of calcium available for the secondary formation of gypsum and ettringite, which is identified as the main reason for the excellent sulfate resistance of the ternary blends. The results suggest that calcined clay – limestone – Portland cements are included in standards as a new type of sulfate-resisting Portland pozzolana cement and Portland composite cement.
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Sulfate resistance of calcined clay – Limestone – Portland cements
Cement and Concrete Research, 2019Co-Authors: Zhenguo Shi, D Herfort, Sergio Ferreiro, Wolfgang Kunther, Josef Kaufmann, Barbara Lothenbach, Mette Rica Geiker, Jorgen SkibstedAbstract:Calcined clays emerge as a promising source of supplementary cementitious material, which can provide a significant lowering of the Portland clinker content in blended cements. This study focusses on sulfate resistance of calcined clay (CC) – limestone (L) – Portland cements for mortars exposed to a 0.11 M Na 2 SO 4 solution at 5 and 20 °C after a hydration period of 91 days. The Pozzolanicity, compressive strength, pore structure, and sulfate resistance of mortars containing laboratory-made metakaolin or calcined montmorillonite and limestone have been investigated in cements with 35 wt% replacement of a white Portland or an ordinary Portland clinker. The results show that all mortars with CC/(CC + L) ≥ 0.5 exhibit excellent sulfate resistance. The consumption of portlandite by the pozzolanic reactions of the calcined clays and the dilution of the Portland clinker lead to a lower amount of calcium available for the secondary formation of gypsum and ettringite, which is identified as the main reason for the excellent sulfate resistance of the ternary blends. The results suggest that calcined clay – limestone – Portland cements are included in standards as a new type of sulfate-resisting Portland pozzolana cement and Portland composite cement.
Juliano Fiorelli - One of the best experts on this subject based on the ideXlab platform.
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effect of mineral additions on the microstructure and properties of blended cement matrices for fibre cement applications
Cement & Concrete Composites, 2019Co-Authors: Julian Eduardo Mejiaballesteros, Holmer Savastano, Juliano Fiorelli, Moises Frias RojasAbstract:Abstract This detailed study of the effect of three mineral additions (limestone, rice husk ash and activated coal mining waste) differing in composition and properties explored the behaviour of blended cements with a 25% replacement ratio. The aim was to select the optimal addition for improving the performance of natural fibre-reinforced cements. The pozzolanic, physical and mechanical properties as well as the pore structure of the blended cement matrices were examined. The findings showed that although rice husk ash is characterised by high Pozzolanicity, it had a less favourable effect on the cement than expected, yielding porous, poorly compacted and hence weak matrices. The activated coal mining waste showed better performance, reaching similar strength to control mortar, better pore size refinement and an important reduction in mean pore size of 60% compared to control mortar after 60 days of curing. In light of those findings, this aluminosilicate addition is proposed as the most apt of the three studied for improving the quality of fibre-reinforced cements, keeping in mind that the interaction effect amongst the three mineral additions was not considered in the present work.
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PHYSICO-CHEMICALANALYSIS OF THE CASHEW NUT PRODUCTION WASTE AIMING THEIR USE IN CEMENT COMPOSITES / ANÁLISE FÍSICO-QUÍMICA DA CINZA DA CASCA DA CASTANHA DE CAJU VISANDO SUAAPLICAÇÃO EM MATERIAIS CIMENTÍCIOS
Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP), 2009Co-Authors: Sofia AraÚjo Lima, JoÃo Adriano Rossignolo, Holmer Savastano, Juliano FiorelliAbstract:Ashes have a prominent place among the agroindustrial wastes, as they result from the energy generation process. Most ashes have pozzolanic activity, and may be used as a cement replacement material, resulting in less energy waste and low cost composite. The present paper investigates the physical and chemical properties of cashew nut shell ash (CNSA) by the following measurement tests: chemical analysis, bulk density, specific mass, leaching and solubilization process, X-Ray diffraction (XRD), scanning electron microscopy (SEM) and specific surface area (BET). A low content of silicon (SiO2) was observed by means of the chemical tests and heavy metals were found in the analysis of the CNSA solubilized extract. These results will be important for the determination of the Pozzolanicity of CNSA in a next stage, as well as the development of a new product for civil building reducing the solubilization of the CNSA in the environment.