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Khandaker M A Hossain - One of the best experts on this subject based on the ideXlab platform.
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performance of volcanic ash and pumice based Blended Cement concrete in mixed sulfate environment
Cement and Concrete Research, 2006Co-Authors: Khandaker M A Hossain, Mohamed LachemiAbstract:Abstract The deterioration of concrete structures due to the presence of mixed sulfate in soils, groundwater and marine environments is a well-known phenomenon. The use of Blended Cements incorporating supplementary Cementing materials and Cements with low C3A content is becoming common in such aggressive environments. This paper presents the results of an investigation on the performance of 12 volcanic ash (VA) and finely ground volcanic pumice (VP) based ASTM Type I and Type V (low C3A) Blended Cement concrete mixtures with varying immersion period of up to 48 months in environments characterized by the presence of mixed magnesium–sodium sulfates. The concrete mixtures comprise a combination of two Portland Cements (Type I and Type V) and four VA/VP based Blended Cements with two water-to-binder ratio of 0.35 and 0.45. Background experiments (in addition to strength and fresh properties) including X-ray diffraction (XRD), Differential scanning calorimetry (DSC), mercury intrusion porosimetry (MIP) and rapid chloride permeability (RCP) were conducted on all concrete mixtures to determine phase composition, pozzolanic activity, porosity and chloride ion resistance. Deterioration of concrete due to mixed sulfate attack and corrosion of reinforcing steel were evaluated by assessing concrete weight loss and measuring corrosion potentials and polarization resistance at periodic intervals throughout the immersion period of 48 months. Plain (Type I/V) Cement concretes, irrespective of their C3A content performed better in terms of deterioration and corrosion resistance compared to Type I/V VA/VP based Blended Cement concrete mixtures in mixed sulfate environment.
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performance of volcanic ash and pumice based Blended Cement concrete in mixed sulfate environment
Cement and Concrete Research, 2006Co-Authors: Khandaker M A Hossain, Mohamed LachemiAbstract:The deterioration of concrete structures due to the presence of mixed sulfate in soils, groundwater and marine environments is a well-known phenomenon. The use of Blended Cements incorporating supplementary Cementing materials and Cements with low C{sub 3}A content is becoming common in such aggressive environments. This paper presents the results of an investigation on the performance of 12 volcanic ash (VA) and finely ground volcanic pumice (VP) based ASTM Type I and Type V (low C{sub 3}A) Blended Cement concrete mixtures with varying immersion period of up to 48 months in environments characterized by the presence of mixed magnesium-sodium sulfates. The concrete mixtures comprise a combination of two Portland Cements (Type I and Type V) and four VA/VP based Blended Cements with two water-to-binder ratio of 0.35 and 0.45. Background experiments (in addition to strength and fresh properties) including X-ray diffraction (XRD), Differential scanning calorimetry (DSC), mercury intrusion porosimetry (MIP) and rapid chloride permeability (RCP) were conducted on all concrete mixtures to determine phase composition, pozzolanic activity, porosity and chloride ion resistance. Deterioration of concrete due to mixed sulfate attack and corrosion of reinforcing steel were evaluated by assessing concrete weight loss and measuring corrosion potentials and polarization resistance atmore » periodic intervals throughout the immersion period of 48 months. Plain (Type I/V) Cement concretes, irrespective of their C{sub 3}A content performed better in terms of deterioration and corrosion resistance compared to Type I/V VA/VP based Blended Cement concrete mixtures in mixed sulfate environment.« less
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Blended Cement using volcanic ash and pumice
Cement and Concrete Research, 2003Co-Authors: Khandaker M A HossainAbstract:Abstract This paper reports the results of investigation to assess the suitability of volcanic ash (VA) and pumice powder (VPP) for Blended Cement production. Tests were conducted on Cement where Portland Cement (PC) was replaced by VA and VPP within the range of 0 to 50%. The physical and chemical properties of VA and VPP were critically reviewed to evaluate the possible influences on Cement properties. The investigation included testing on both fresh and hardened states of Cement paste. The standard tests conducted on different PC–VA and –VPP mixtures provided encouraging results, comparable to those for fly ash (FA) Cement, and showed good potential of manufacturing Blended Portland volcanic ash Cement (PVAC) and Portland volcanic pumice Cement (PVPC) with higher setting time and low heat of hydration using up to 20% replaCement.
Mohamed Lachemi - One of the best experts on this subject based on the ideXlab platform.
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performance of volcanic ash and pumice based Blended Cement concrete in mixed sulfate environment
Cement and Concrete Research, 2006Co-Authors: Khandaker M A Hossain, Mohamed LachemiAbstract:The deterioration of concrete structures due to the presence of mixed sulfate in soils, groundwater and marine environments is a well-known phenomenon. The use of Blended Cements incorporating supplementary Cementing materials and Cements with low C{sub 3}A content is becoming common in such aggressive environments. This paper presents the results of an investigation on the performance of 12 volcanic ash (VA) and finely ground volcanic pumice (VP) based ASTM Type I and Type V (low C{sub 3}A) Blended Cement concrete mixtures with varying immersion period of up to 48 months in environments characterized by the presence of mixed magnesium-sodium sulfates. The concrete mixtures comprise a combination of two Portland Cements (Type I and Type V) and four VA/VP based Blended Cements with two water-to-binder ratio of 0.35 and 0.45. Background experiments (in addition to strength and fresh properties) including X-ray diffraction (XRD), Differential scanning calorimetry (DSC), mercury intrusion porosimetry (MIP) and rapid chloride permeability (RCP) were conducted on all concrete mixtures to determine phase composition, pozzolanic activity, porosity and chloride ion resistance. Deterioration of concrete due to mixed sulfate attack and corrosion of reinforcing steel were evaluated by assessing concrete weight loss and measuring corrosion potentials and polarization resistance atmore » periodic intervals throughout the immersion period of 48 months. Plain (Type I/V) Cement concretes, irrespective of their C{sub 3}A content performed better in terms of deterioration and corrosion resistance compared to Type I/V VA/VP based Blended Cement concrete mixtures in mixed sulfate environment.« less
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performance of volcanic ash and pumice based Blended Cement concrete in mixed sulfate environment
Cement and Concrete Research, 2006Co-Authors: Khandaker M A Hossain, Mohamed LachemiAbstract:Abstract The deterioration of concrete structures due to the presence of mixed sulfate in soils, groundwater and marine environments is a well-known phenomenon. The use of Blended Cements incorporating supplementary Cementing materials and Cements with low C3A content is becoming common in such aggressive environments. This paper presents the results of an investigation on the performance of 12 volcanic ash (VA) and finely ground volcanic pumice (VP) based ASTM Type I and Type V (low C3A) Blended Cement concrete mixtures with varying immersion period of up to 48 months in environments characterized by the presence of mixed magnesium–sodium sulfates. The concrete mixtures comprise a combination of two Portland Cements (Type I and Type V) and four VA/VP based Blended Cements with two water-to-binder ratio of 0.35 and 0.45. Background experiments (in addition to strength and fresh properties) including X-ray diffraction (XRD), Differential scanning calorimetry (DSC), mercury intrusion porosimetry (MIP) and rapid chloride permeability (RCP) were conducted on all concrete mixtures to determine phase composition, pozzolanic activity, porosity and chloride ion resistance. Deterioration of concrete due to mixed sulfate attack and corrosion of reinforcing steel were evaluated by assessing concrete weight loss and measuring corrosion potentials and polarization resistance at periodic intervals throughout the immersion period of 48 months. Plain (Type I/V) Cement concretes, irrespective of their C3A content performed better in terms of deterioration and corrosion resistance compared to Type I/V VA/VP based Blended Cement concrete mixtures in mixed sulfate environment.
Prinya Chindaprasirt - One of the best experts on this subject based on the ideXlab platform.
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assessing the effect of biomass ashes with different finenesses on the compressive strength of Blended Cement paste
Materials & Design, 2012Co-Authors: Theerawat Sinsiri, Chai Jaturapitakkul, Wunchock Kroehong, Prinya ChindaprasirtAbstract:Abstract This study assesses the effect of biomass ashes with different finenesses on the compressive strength of Blended Cement paste. rice husk ash (RHA), palm oil fuel ash (POFA) and river sand (RS) were ground to obtain two finenesses: one was the same size as the Cement, and the other was smaller than the Cement. Type I Portland Cement was replaced by RHA, POFA and RS at 0%, 10%, 20%, 30% and 40% by weight of binder. A water to binder ratio (W/B) of 0.35 was used for all Blended Cement paste mixes. The percentages of amorphous materials and the compressive strength of the pastes due to the hydration reaction, filler effect and pozzolanic reaction were investigated. The results showed that ground rice husk ash and ground palm oil fuel ash were composed of amorphous silica material. The compressive strength of the pastes due to the hydration reaction decreased with decreasing Cement content. The compressive strength of the pastes due to the filler effect increased with increasing Cement replaCement. The compressive strengths of the pastes due to the pozzolanic reaction were nonlinear and were fit with nonlinear isotherms that increased with increasing fineness of RHA and POFA, Cement replaCement rate and age of the paste. In addition, the model that was proposed to predict the percentage compressive strength of the Blended Cement pastes on the basis of the age of the paste and the percentage replaCement with biomass ash was in good agreement with the experimental results. The optimum replaCement level of rice husk ash and palm oil fuel ash in pastes was 30% by weight of binder; this replaCement percentage resulted in good compressive strengths.
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Effect of palm oil fuel ash fineness on the microstructure of Blended Cement paste
Construction and Building Materials, 2011Co-Authors: Wunchock Kroehong, Theerawat Sinsiri, Chai Jaturapitakkul, Prinya ChindaprasirtAbstract:Abstract This paper presents the effect of palm oil fuel ash fineness on the microstructure of Blended Cement paste. Palm oil fuel ash (POFA) was ground to two different finenesses. Coarse and high fineness palm oil fuel ash, with median particle sizes of 15.6 and 2.1 μm, respectively, were used to replace ordinary Portland Cement (OPC) at 0%, 20% and 40% by binder weight. A water to binder ( W / B ) ratio of 0.35 was used for all Blended Cement pastes. The amorphous ground palm oil fuel ash was characterized by the Rietveld method. The compressive strength, thermogravimetric analysis and pore size distribution of the Blended Cement pastes were investigated. The test results indicate that the ground palm oil fuel ash was an amorphous silica material. The compressive strengths of the Blended Cement pastes containing coarse POFA were as high as that of OPC Cement paste. Blended Cement paste with high fineness POFA had a higher compressive strength than that with coarse POFA. The Blended Cement pastes containing 20% of POFA with high fineness had the lowest total porosity. The Ca(OH) 2 contents of Blended Cement paste containing POFA decreased with increasing replaCement of POFA and were lower than those of the OPC Cement paste. In addition, the POFA fineness had an effect on the reduction rate of Ca(OH) 2 . Furthermore, the critical pore size and average pore size of Blended Cement paste containing POFA were lower than those of the OPC Cement paste. The incorporation of high fineness POFA decreased the critical pore size and the average pore size of Blended Cement paste as compared to that with coarse POFA.
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THE EFFECT OF ZEOLITE ON MICROSTRUCTURE OF Blended Cement PASTE
2008Co-Authors: Chuwit Napia, Theerawat Sinsiri, Prinya ChindaprasirtAbstract:This paper presents the effect of zeolite on microstructure of hardened Blended Cement pastes. Synthesise zeolite was used to partially replace Portland Cement type I at the rate of 0, 20, and 40% by weight of binder. The water to binder ratio (W/B) of 0.35 was used for all the Blended Cement paste mixtures. XRD and DTA were used to investigate the pozzolanic reaction of Blended Cement paste and fractured surface of Blended Cement paste was studied by SEM. The pore size distribution of Blended Cement paste was studied by MIP. Test results indicated that the pozzolanic reaction of Blended Cement paste was significantly affected by the replaCement of zeolite. The Ca(OH)2 of Blended Cement paste decreased with an increase in zeolite content at the longer curing. SEM results revealed that the pastes with zeolite became denser. The porosity and pore size of Blended Cement paste was significantly affected by the replaCement of zeolite. The replaCement of Portland Cement by zeolite increased the total porosity but decreased the average pore size of the paste. The large capillary porosity trended to decreased and medium capillary porosity increased as a result of the addition of zeolite.
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effect of fly ash fineness on microstructure of Blended Cement paste
Construction and Building Materials, 2007Co-Authors: Prinya Chindaprasirt, Chai Jaturapitakkul, Theerawat SinsiriAbstract:Abstract This research demonstrates the effect of fly ash fineness on pore size and microstructure of hardened Blended Cement pastes. Two sizes of fly ash, original fly ash and classified fly ash were used to replace Portland Cement type I paste. Test results indicated that the pore sizes of hardened Blended Cement paste were significantly affected by the rate of replaCement and the fineness of fly ash. The replaCement of Cement by original fly ash decreased the pore sizes of Blended Cement paste and the incorporation of classified fly ash resulted in a further decrease in the pore sizes of Blended Cement paste. The X-ray diffraction (XRD) results showed that the Blended Cement paste with classified fly ash was more effective at reducing the intensity of Ca(OH)2 than that with the original fly ash. The scanning electron microscope (SEM) results revealed that the hardened Blended Cement paste containing finer fly ash produced a denser structure than the one containing coarser fly ash.
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effect of fly ash fineness on compressive strength and pore size of Blended Cement paste
Cement & Concrete Composites, 2005Co-Authors: Prinya Chindaprasirt, Chai Jaturapitakkul, Theerawat SinsiriAbstract:Abstract This paper presents an experimental investigation on the effect of fly ash fineness on compressive strength, porosity, and pore size distribution of hardened Cement pastes. Class F fly ash with two fineness, an original fly ash and a classified fly ash, with median particle size of 19.1 and 6.4 μm respectively were used to partially replace portland Cement at 0%, 20%, and 40% by weight. The water to binder ratio (w/b) of 0.35 was used for all the Blended Cement paste mixes. Test results indicated that the Blended Cement paste with classified fly ash produced paste with higher compressive strength than that with original fly ash. The porosity and pore size of Blended Cement paste was significantly affected by the replaCement of fly ash and its fineness. The replaCement of portland Cement by original fly ash increased the porosity but decreased the average pore size of the paste. The measured gel porosity (5.7–10 nm) increased with an increase in the fly ash content. The incorporation of classified fly ash decreased the porosity and average pore size of the paste as compared to that with ordinary fly ash. The total porosity and capillary pores decreased while the gel pore increased as a result of the addition of finer fly ash at all replaCement levels.
Theerawat Sinsiri - One of the best experts on this subject based on the ideXlab platform.
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The Effect of Palm Oil Fuel Ash as a Supplementary Cementitious Material on Chloride Penetration and Microstructure of Blended Cement Paste
Arabian Journal for Science and Engineering, 2016Co-Authors: Wunchock Kroehong, Theerawat Sinsiri, Nattapong Damrongwiriyanupap, Chai JaturapitakkulAbstract:This article presents the effect of palm oil fuel ash as a supplementary Cementitious material on chloride penetration and microstructure of Blended Cement paste. Palm oil fuel ash (POFA) was ground to obtain two finenesses: one was the same size as the Cement and the other was smaller than the Cement. Type I ordinary Portland Cement (OPC) was replaced by POFA at 0, 10, 20, 30, and 40% by weight of binder. All paste specimens were prepared using the same water to binder ratio as 0.35. The compressive strength, pore size distribution, total chloride content, free chloride content, and X-ray diffraction analysis of chloride penetration into Blended Cement pastes were investigated. The results indicated that, at 60 and 90 days, the Blended Cement pastes containing 30% of POFA with high fineness had 1.6 and 4.9% higher compressive strength than that of the OPC paste, respectively. POFA pastes had a lower chloride diffusion coefficient and shallower concentration profile of free chloride than that of the OPC paste. The specimens containing coarse fineness and small particle size POFA had lower chloride diffusion coefficient than OPC paste ranging between 13.2 and 61.0%. In addition, the chloride diffusion coefficient is linearly correlated with the critical pore diameters. ReplaCement of OPC by the fine-grained POFA resulted in the decrease in free chloride and in the chloride diffusion coefficient.
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assessing the effect of biomass ashes with different finenesses on the compressive strength of Blended Cement paste
Materials & Design, 2012Co-Authors: Theerawat Sinsiri, Chai Jaturapitakkul, Wunchock Kroehong, Prinya ChindaprasirtAbstract:Abstract This study assesses the effect of biomass ashes with different finenesses on the compressive strength of Blended Cement paste. rice husk ash (RHA), palm oil fuel ash (POFA) and river sand (RS) were ground to obtain two finenesses: one was the same size as the Cement, and the other was smaller than the Cement. Type I Portland Cement was replaced by RHA, POFA and RS at 0%, 10%, 20%, 30% and 40% by weight of binder. A water to binder ratio (W/B) of 0.35 was used for all Blended Cement paste mixes. The percentages of amorphous materials and the compressive strength of the pastes due to the hydration reaction, filler effect and pozzolanic reaction were investigated. The results showed that ground rice husk ash and ground palm oil fuel ash were composed of amorphous silica material. The compressive strength of the pastes due to the hydration reaction decreased with decreasing Cement content. The compressive strength of the pastes due to the filler effect increased with increasing Cement replaCement. The compressive strengths of the pastes due to the pozzolanic reaction were nonlinear and were fit with nonlinear isotherms that increased with increasing fineness of RHA and POFA, Cement replaCement rate and age of the paste. In addition, the model that was proposed to predict the percentage compressive strength of the Blended Cement pastes on the basis of the age of the paste and the percentage replaCement with biomass ash was in good agreement with the experimental results. The optimum replaCement level of rice husk ash and palm oil fuel ash in pastes was 30% by weight of binder; this replaCement percentage resulted in good compressive strengths.
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Effect of palm oil fuel ash fineness on the microstructure of Blended Cement paste
Construction and Building Materials, 2011Co-Authors: Wunchock Kroehong, Theerawat Sinsiri, Chai Jaturapitakkul, Prinya ChindaprasirtAbstract:Abstract This paper presents the effect of palm oil fuel ash fineness on the microstructure of Blended Cement paste. Palm oil fuel ash (POFA) was ground to two different finenesses. Coarse and high fineness palm oil fuel ash, with median particle sizes of 15.6 and 2.1 μm, respectively, were used to replace ordinary Portland Cement (OPC) at 0%, 20% and 40% by binder weight. A water to binder ( W / B ) ratio of 0.35 was used for all Blended Cement pastes. The amorphous ground palm oil fuel ash was characterized by the Rietveld method. The compressive strength, thermogravimetric analysis and pore size distribution of the Blended Cement pastes were investigated. The test results indicate that the ground palm oil fuel ash was an amorphous silica material. The compressive strengths of the Blended Cement pastes containing coarse POFA were as high as that of OPC Cement paste. Blended Cement paste with high fineness POFA had a higher compressive strength than that with coarse POFA. The Blended Cement pastes containing 20% of POFA with high fineness had the lowest total porosity. The Ca(OH) 2 contents of Blended Cement paste containing POFA decreased with increasing replaCement of POFA and were lower than those of the OPC Cement paste. In addition, the POFA fineness had an effect on the reduction rate of Ca(OH) 2 . Furthermore, the critical pore size and average pore size of Blended Cement paste containing POFA were lower than those of the OPC Cement paste. The incorporation of high fineness POFA decreased the critical pore size and the average pore size of Blended Cement paste as compared to that with coarse POFA.
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THE EFFECT OF ZEOLITE ON MICROSTRUCTURE OF Blended Cement PASTE
2008Co-Authors: Chuwit Napia, Theerawat Sinsiri, Prinya ChindaprasirtAbstract:This paper presents the effect of zeolite on microstructure of hardened Blended Cement pastes. Synthesise zeolite was used to partially replace Portland Cement type I at the rate of 0, 20, and 40% by weight of binder. The water to binder ratio (W/B) of 0.35 was used for all the Blended Cement paste mixtures. XRD and DTA were used to investigate the pozzolanic reaction of Blended Cement paste and fractured surface of Blended Cement paste was studied by SEM. The pore size distribution of Blended Cement paste was studied by MIP. Test results indicated that the pozzolanic reaction of Blended Cement paste was significantly affected by the replaCement of zeolite. The Ca(OH)2 of Blended Cement paste decreased with an increase in zeolite content at the longer curing. SEM results revealed that the pastes with zeolite became denser. The porosity and pore size of Blended Cement paste was significantly affected by the replaCement of zeolite. The replaCement of Portland Cement by zeolite increased the total porosity but decreased the average pore size of the paste. The large capillary porosity trended to decreased and medium capillary porosity increased as a result of the addition of zeolite.
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effect of fly ash fineness on microstructure of Blended Cement paste
Construction and Building Materials, 2007Co-Authors: Prinya Chindaprasirt, Chai Jaturapitakkul, Theerawat SinsiriAbstract:Abstract This research demonstrates the effect of fly ash fineness on pore size and microstructure of hardened Blended Cement pastes. Two sizes of fly ash, original fly ash and classified fly ash were used to replace Portland Cement type I paste. Test results indicated that the pore sizes of hardened Blended Cement paste were significantly affected by the rate of replaCement and the fineness of fly ash. The replaCement of Cement by original fly ash decreased the pore sizes of Blended Cement paste and the incorporation of classified fly ash resulted in a further decrease in the pore sizes of Blended Cement paste. The X-ray diffraction (XRD) results showed that the Blended Cement paste with classified fly ash was more effective at reducing the intensity of Ca(OH)2 than that with the original fly ash. The scanning electron microscope (SEM) results revealed that the hardened Blended Cement paste containing finer fly ash produced a denser structure than the one containing coarser fly ash.
C Varga - One of the best experts on this subject based on the ideXlab platform.
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metakaolin sand Blended Cement pastes rheology hydration process and mechanical properties
Construction and Building Materials, 2010Co-Authors: Ivan Janotka, Marta Kuliffayova, M. Palacios, Francisca Puertas, C VargaAbstract:Abstract In the present work, the use of three Slovak poor metakaolin sands with different metakaolin content (36.0% (MK-1), 31.5 (MK-2) and 40.0% (MK-3)) and specific surface has been deeply studied as mineral addition for Portland Cement. The percentage of metakaolin sands in the Blended Cements was 10%, 20% and 40%. The pozzolanic tests confirm that the three metakaolin sands show a high pozzolanic activity, comparable to a commercial metakaolin and silica fume. With respect to the rheological behaviour, metakaolin sand–Blended-Cement pastes fit to Herchel–Bulkley model and their yield stress increases as the metakaolin content increases. MK-3 sand with the highest pozzolanic activity and highest specific surface induces the highest increase of the yield stress. From the calorimetric results it is concluded that the addition of MK-1 and MK-2 sands to Portland Cement induces a delay up to 2 h of the precipitation of the main hydration products in the Blended-Cement pastes and decreases the maximum heat evolution rate. On the contrary, the incorporation of 40% of MK-3 sand shortens 6 h its apparition and increases significantly the maximum heat evolution rate. Additionally, the presence of the metakaolin sands reduces the heat released during the hydration process with respect to non-Blended-Cement pastes. The incorporation of metakaolin sand induces a decrease of the mechanical strength, being the decrease higher as the metakaolin sand content increases although they also produce a refinement in the pore structure and a decrease of the permeability.
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Metakaolin sand–Blended-Cement pastes: Rheology, hydration process and mechanical properties
Construction and Building Materials, 2010Co-Authors: Ivan Janotka, Marta Kuliffayova, M. Palacios, Francisca Puertas, C VargaAbstract:Abstract In the present work, the use of three Slovak poor metakaolin sands with different metakaolin content (36.0% (MK-1), 31.5 (MK-2) and 40.0% (MK-3)) and specific surface has been deeply studied as mineral addition for Portland Cement. The percentage of metakaolin sands in the Blended Cements was 10%, 20% and 40%. The pozzolanic tests confirm that the three metakaolin sands show a high pozzolanic activity, comparable to a commercial metakaolin and silica fume. With respect to the rheological behaviour, metakaolin sand–Blended-Cement pastes fit to Herchel–Bulkley model and their yield stress increases as the metakaolin content increases. MK-3 sand with the highest pozzolanic activity and highest specific surface induces the highest increase of the yield stress. From the calorimetric results it is concluded that the addition of MK-1 and MK-2 sands to Portland Cement induces a delay up to 2 h of the precipitation of the main hydration products in the Blended-Cement pastes and decreases the maximum heat evolution rate. On the contrary, the incorporation of 40% of MK-3 sand shortens 6 h its apparition and increases significantly the maximum heat evolution rate. Additionally, the presence of the metakaolin sands reduces the heat released during the hydration process with respect to non-Blended-Cement pastes. The incorporation of metakaolin sand induces a decrease of the mechanical strength, being the decrease higher as the metakaolin sand content increases although they also produce a refinement in the pore structure and a decrease of the permeability.
