The Experts below are selected from a list of 216 Experts worldwide ranked by ideXlab platform
V. Praveen - One of the best experts on this subject based on the ideXlab platform.
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Shear Behaviour of Hybrid Fibre Reinforced Geopolymer Concrete Beams
International Journal of Research, 2017Co-Authors: J.mahesh Kumar, V. PraveenAbstract:Concrete is the most common material for construction. The demand for concrete as a construction material leads to the increase of demand for Portland cement. Concrete is known as a significant contributor to the emission of greenhouse gases. The cement industry is the second largest producer of the greenhouse gas. The environmental problems caused by cement production can be reduced by finding an alternate material. One of potential material to substitute for conventional concrete is geopolymer concrete. Geopolymer concrete is an inorganic alumino-silicate polymer synthesized from predominantly silicon, aluminium and by product materials such as fly ash, GGBS (ground granulated blast furnace slag). Geopolymer concrete does not contain cement. Hybrid fibres were used in this study. Hybrid fibre is the combination of steel fibre and basalt fibre with different volume fractions. When these fibres are added to this special concrete it improves the ductile behaviour and energy absorption capacity. This is due to the property of steel and basalt fibre to bridge the crack development inside the concrete. The main objective of the study is to look into the shear behaviour of hybrid fibre reinforced geopolymer concrete beams. Test specimens of 1200×150×100 mm size were used for the study. 20-30% of Fly ash by the mass was replaced by GGBS. The variable used were percentage of steel fibre volume fraction viz. 0.0%, 0.5%, and 1%, and basalt fibre volume fraction viz. 0.0%, 0.15%,and 0.3%. The concentration of sodium hydroxide was 12Molar and 14 Molar in geopolymer concrete. For Curing, temperature was fixed as 60 0 C for 24 hours. The geopolymer specimens were cured by using steam Curing Chamber. The specimens were cured after the rest period of three days. A trail and error process was used to obtain proper mixture proportion for geopoymer concrete. The specimens were tested after the age of 7 days. The obtained results of Fly ash and GGBS -based hybrid fibre geopolymer concrete (F&GHGPC) specimens were compared with the only Fly ash-based hybrid fibre geopolymer concrete (FHGPC) specimens. Test results shows that first crack load, ultimate load, energy absorption capacity, experimental shear strength and ductile characteristic of F&GHGPC geopolymer concrete specimens were higher than the FHGPC geopolymer concrete specimens.
J.mahesh Kumar - One of the best experts on this subject based on the ideXlab platform.
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Shear Behaviour of Hybrid Fibre Reinforced Geopolymer Concrete Beams
International Journal of Research, 2017Co-Authors: J.mahesh Kumar, V. PraveenAbstract:Concrete is the most common material for construction. The demand for concrete as a construction material leads to the increase of demand for Portland cement. Concrete is known as a significant contributor to the emission of greenhouse gases. The cement industry is the second largest producer of the greenhouse gas. The environmental problems caused by cement production can be reduced by finding an alternate material. One of potential material to substitute for conventional concrete is geopolymer concrete. Geopolymer concrete is an inorganic alumino-silicate polymer synthesized from predominantly silicon, aluminium and by product materials such as fly ash, GGBS (ground granulated blast furnace slag). Geopolymer concrete does not contain cement. Hybrid fibres were used in this study. Hybrid fibre is the combination of steel fibre and basalt fibre with different volume fractions. When these fibres are added to this special concrete it improves the ductile behaviour and energy absorption capacity. This is due to the property of steel and basalt fibre to bridge the crack development inside the concrete. The main objective of the study is to look into the shear behaviour of hybrid fibre reinforced geopolymer concrete beams. Test specimens of 1200×150×100 mm size were used for the study. 20-30% of Fly ash by the mass was replaced by GGBS. The variable used were percentage of steel fibre volume fraction viz. 0.0%, 0.5%, and 1%, and basalt fibre volume fraction viz. 0.0%, 0.15%,and 0.3%. The concentration of sodium hydroxide was 12Molar and 14 Molar in geopolymer concrete. For Curing, temperature was fixed as 60 0 C for 24 hours. The geopolymer specimens were cured by using steam Curing Chamber. The specimens were cured after the rest period of three days. A trail and error process was used to obtain proper mixture proportion for geopoymer concrete. The specimens were tested after the age of 7 days. The obtained results of Fly ash and GGBS -based hybrid fibre geopolymer concrete (F&GHGPC) specimens were compared with the only Fly ash-based hybrid fibre geopolymer concrete (FHGPC) specimens. Test results shows that first crack load, ultimate load, energy absorption capacity, experimental shear strength and ductile characteristic of F&GHGPC geopolymer concrete specimens were higher than the FHGPC geopolymer concrete specimens.
Ying Bo Lv - One of the best experts on this subject based on the ideXlab platform.
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Research on Produced Fluid Corrosion Resistance Oil Well Cement Paste System in Adjustment Well
Materials Science Forum, 2016Co-Authors: Jing Fu Zhang, Jun Dong Chen, Yu Wang, Ying Bo LvAbstract:To design oil well cement paste system and ensure well cementation quality of adjustment well in work area of tertiary oil recovery (EOR), the composition, microstructure and strength of cement paste matrix eroded by producing water were tested and studied by HTHP Curing Chamber, HTHP corrosion tester, X-ray diffraction, scanning electron microscope (SEM), universal testing compressor and some other laboratory equipment according to the condition that producing water contains sulfate (SO42-) and bicarbonate (HCO3-). The corrosion law and mechanism of oil well cement paste matrix were analyzed. The problem for designing corrosion resistance oil well cement paste system was investigated. The corrosion law and mechanism of oil well cement paste matrix by SO42- and HCO3- were raised. The corrosion resistant oil well cement paste system was designed, which was suitable to the adjustment well in area of EOR in Daqing. The results show that the compositions of cement paste matrix changed after corrosion by SO42- and HCO3- for a long term. The secondary gypsum, ettringite and calcite were produced, which changed the microstructures and declined the compressive strength of cement paste matrix. The change degree of compressive strength of cement paste matrix was affected by corrosion media concentration, corrosion time and other conditions. The higher concentration of corrosion media and the longer of corrosion time were, the greater decline of cement strength occurred. The formula of corrosion resistance oil well cement paste system was designed, for which the high sulfate resistant cement as architectural substrate and the PZW as admixtures were used to improve the strength and penetration resistance ability of cement.
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Research on Produced Fluid Corrosion Resistance Oil Well Cement Paste System in Adjustment Well
Materials Science Forum, 2016Co-Authors: Jing Fu Zhang, Jun Dong Chen, Yu Wang, Ying Bo LvAbstract:To design oil well cement paste system and ensure well cementation quality of adjustment well in work area of tertiary oil recovery (EOR), the composition, microstructure and strength of cement paste matrix eroded by producing water were tested and studied by HTHP Curing Chamber, HTHP corrosion tester, X-ray diffraction, scanning electron microscope (SEM), universal testing compressor and some other laboratory equipment according to the condition that producing water contains sulfate (SO42-) and bicarbonate (HCO3-). The corrosion law and mechanism of oil well cement paste matrix were analyzed. The problem for designing corrosion resistance oil well cement paste system was investigated. The corrosion law and mechanism of oil well cement paste matrix by SO42- and HCO3- were raised. The corrosion resistant oil well cement paste system was designed, which was suitable to the adjustment well in area of EOR in Daqing. The results show that the compositions of cement paste matrix changed after corrosion by SO42- and HCO3- for a long term. The secondary gypsum, ettringite and calcite were produced, which changed the microstructures and declined the compressive strength of cement paste matrix. The change degree of compressive strength of cement paste matrix was affected by corrosion media concentration, corrosion time and other conditions. The higher concentration of corrosion media and the longer of corrosion time were, the greater decline of cement strength occurred. The formula of corrosion resistance oil well cement paste system was designed, for which the high sulfate resistant cement as architectural substrate and the PZW as admixtures were used to improve the strength and penetration resistance ability of cement.
Jing Fu Zhang - One of the best experts on this subject based on the ideXlab platform.
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Research on Produced Fluid Corrosion Resistance Oil Well Cement Paste System in Adjustment Well
Materials Science Forum, 2016Co-Authors: Jing Fu Zhang, Jun Dong Chen, Yu Wang, Ying Bo LvAbstract:To design oil well cement paste system and ensure well cementation quality of adjustment well in work area of tertiary oil recovery (EOR), the composition, microstructure and strength of cement paste matrix eroded by producing water were tested and studied by HTHP Curing Chamber, HTHP corrosion tester, X-ray diffraction, scanning electron microscope (SEM), universal testing compressor and some other laboratory equipment according to the condition that producing water contains sulfate (SO42-) and bicarbonate (HCO3-). The corrosion law and mechanism of oil well cement paste matrix were analyzed. The problem for designing corrosion resistance oil well cement paste system was investigated. The corrosion law and mechanism of oil well cement paste matrix by SO42- and HCO3- were raised. The corrosion resistant oil well cement paste system was designed, which was suitable to the adjustment well in area of EOR in Daqing. The results show that the compositions of cement paste matrix changed after corrosion by SO42- and HCO3- for a long term. The secondary gypsum, ettringite and calcite were produced, which changed the microstructures and declined the compressive strength of cement paste matrix. The change degree of compressive strength of cement paste matrix was affected by corrosion media concentration, corrosion time and other conditions. The higher concentration of corrosion media and the longer of corrosion time were, the greater decline of cement strength occurred. The formula of corrosion resistance oil well cement paste system was designed, for which the high sulfate resistant cement as architectural substrate and the PZW as admixtures were used to improve the strength and penetration resistance ability of cement.
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Research on Produced Fluid Corrosion Resistance Oil Well Cement Paste System in Adjustment Well
Materials Science Forum, 2016Co-Authors: Jing Fu Zhang, Jun Dong Chen, Yu Wang, Ying Bo LvAbstract:To design oil well cement paste system and ensure well cementation quality of adjustment well in work area of tertiary oil recovery (EOR), the composition, microstructure and strength of cement paste matrix eroded by producing water were tested and studied by HTHP Curing Chamber, HTHP corrosion tester, X-ray diffraction, scanning electron microscope (SEM), universal testing compressor and some other laboratory equipment according to the condition that producing water contains sulfate (SO42-) and bicarbonate (HCO3-). The corrosion law and mechanism of oil well cement paste matrix were analyzed. The problem for designing corrosion resistance oil well cement paste system was investigated. The corrosion law and mechanism of oil well cement paste matrix by SO42- and HCO3- were raised. The corrosion resistant oil well cement paste system was designed, which was suitable to the adjustment well in area of EOR in Daqing. The results show that the compositions of cement paste matrix changed after corrosion by SO42- and HCO3- for a long term. The secondary gypsum, ettringite and calcite were produced, which changed the microstructures and declined the compressive strength of cement paste matrix. The change degree of compressive strength of cement paste matrix was affected by corrosion media concentration, corrosion time and other conditions. The higher concentration of corrosion media and the longer of corrosion time were, the greater decline of cement strength occurred. The formula of corrosion resistance oil well cement paste system was designed, for which the high sulfate resistant cement as architectural substrate and the PZW as admixtures were used to improve the strength and penetration resistance ability of cement.
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Development and Change of Compressive Strength for Class G Oil Well Cement under High Temperature
Advanced Materials Research, 2014Co-Authors: Jing Fu Zhang, Kai Liu, Rui Xue Hou, Bo Wang, Jin Long YangAbstract:The compressive strength of oil well cement would be damaged by high temperature in deep oil wells, which was caused by the obvious change of the components and microstructure of cement hydration products. The adaptability of common oil well cement for cementing under higher temperatures was confined by above reasons. Characteristics of development and change of compressive strength of Class G oil well cement were studied under different temperatures by using Static Gel Strength Analyzer and High Temperature-High Pressure Curing Chamber. The influence law of temperature and silica sands on compressive strength was analyzed. The results showed that the critical temperatures at which the compressive strength begun to decline were about 110°C and 150°C respectively; The compressive strength increased with Curing time during the initial period and would reduced after it reached a certain value when temperature exceeded 110°C; For cement with silica sands, the compressive strength development trend was in the shape of two-stage form with increase of Curing time within the range of 110~150°C, but for 160~200°C temperature range the development form was in the shape of single stage; The reasonable amounts of silica sands which would be added to cement slurry to enhance the compressive strength of hardening paste were determined to be 30%~40%.
Dulce Maria De Araújo Melo - One of the best experts on this subject based on the ideXlab platform.
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Effect of sugarcane biomass waste in cement slurries submitted to high temperature and pressure
Materials Science and Engineering: A, 2011Co-Authors: Marcos A.s. Anjos, Antonio Eduardo Martinelli, Dulce Maria De Araújo MeloAbstract:Abstract Cementitious materials are subjected to changes in their microstructure and mechanical behavior when submitted to high service temperatures. In the oil industry, Portland-based slurries are used where conditions imply high temperatures and high pressures, e.g., steam injection or recovery of heavy oils. The present study investigated the hydration behavior and mechanical strength of cement slurries containing sugarcane biomass waste or silica flour, submitted to high temperature and pressure cycles using a Curing Chamber. The slurries were initially cured for 28 days at 22 °C. After that, they were placed in a Curing Chamber for 3 days at 280 °C and 17.6 MPa. The results showed a decrease in the compressive strength of the slurries submitted to high temperature high pressure. The decrease in strength was less marked in the slurry containing 40% of sugarcane biomass waste, as a consequence of the formation of silica-rich phases, i.e., xonotlite and tobermorite. When the slurries were placed in the Curing Chamber at 280 °C and 6.9 MPa for 7 days (after initial Curing for 14 days at 38 °C), the slurry containing 59% sugarcane biomass waste showed an increase in compressive strength, contrary to what was observed for all the other slurries tested.
