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Showing 1 to 10 of 10 for “"Spacing Factor"”.
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EFFECT OF CRACK-REDUCING TECHNOLOGIES AND SUPPLEMENTARY CEMENTITIOUS MATERIALS ON SETTLEMENT CRACKING OF PLASTIC CONCRETE AND DURABILITY PERFORMANCE OF HARDENED CONCRETE
… of durability, mixtures with an average air-void spacing factor of 0.007 in. (0.18 mm) or less performed well in the freeze-thaw test. Mixtures with an average air-void spacing factor of 0.007 in. (0.18 mm) or less and a compressive strength greater than 4000 psi (27.6 MPa) performed well in the …
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Evaluating CEN/TS 12390-9 To Assess Concrete for UK Freeze-Thaw Exposure Conditions
… (air content of hardened concrete, spacing factor, specific surface, void frequency average chord length and microair content) and subsequent freeze-thaw resistance. The study also examined the effect of cement type in concretes with a range of target air contents (7.0%, 9.5% and …
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Advances in measuring parameters of the air-void system in hardened concrete
… or establish a clear relationship between the spacing of air void, the freezing rate and the paste properties. In many respects, these theories complement each other. Air entrainment is effective and reliable to resist freezing and thawing for concrete designed for outside exposure in the cold …
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Microstructure characterization of foamed cement and concrete
… air system. Instead, parameters such as bubble spacing factor measured on polished sections are more useful for assessing freeze-thaw durability. This study is motivated by concerns about how vibration and handling of fresh concrete may affect air void parameters. Fresh concrete mixtures were …
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Determining the Air Void Parameters of Concrete Using Digital Image Analysis of Polarized Light Micrographs
The ASTM C457 test has long been a standard used to obtain the air void parameters of concrete materials. These air void parameters provide valuable information that has been linked to the performance of concrete under conditions such as freezing and thawing cycles. The standard test procedure …
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Analysis of air-void system in hardened concrete from a three-dimensional perspective
… by freezing water. An ASTM C457 parameter – spacing factor – quantifies the proximity of paste to air bubbles in the microstructure. This study shows that parameters derived from one-dimensional measurements, such as the ASTM C457 method, or two-dimensional measurements, such as from images …
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Multicriteria Decision Method for Renewable Energy Production: Siting Solar, Wind and SHP Plants in Zimbabwe
… of solar resources, PV module efficiency, spacing factor, and accessible land area are some examples of the information that must be gathered in order to derive the technical potential for the creation of solar PV systems. Addressing obstacles to the widespread adoption of renewable energy …
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Developing An Alternative Hardened Concrete Air Void Characterization Method
… of air) and further information such as the spacing factor and specific surface can be calculated from this data. This entire process was developed by producing four concrete mixtures with different air entraining dosages. The air entraining dosages were added at various ranges sufficient to …
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Freeze-Thaw Resistance and Microstructural Characteristics of Concretes Containing Pozzolans
… concretes. Based on a criterion that unsatisfactory resistance to freezing and thawing corresponds to a durability factor (DF) less than 60% or a change in length greater than 200 μm/m, all the air-entrained concretes exhibited excellent performance under freeze-thaw conditions irrespective …
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Macro - and Microstructure Evaluation and Field Applications of Concrete with Recycled Glass Pozzolan
… matrix. Adding more GP results in smaller spacing factor and higher surface area of air voids, which improves resistance to freeze-thaw and thus increases durability.</p> <p>This research was applied in field projects for sidewalks and high-rise buildings. It is significant that this work …