Physical and Chemical Actions of Nano-Mineral Additives on Properties of High-Volume Fly Ash Engineered Cementitious Composites
[ X ]
Tarih
2016
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Amer Concrete Inst
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Unlike conventional concrete, the material design process for engineered cementitious composites (ECC) involves micromechanics-based design theory, paving the way for the use of high volumes of fly ash (HVFA) as a major component. Using high volumes of fly ash (up to 85% weight fraction of cement) in ECC mixtures enables improved tensile ductility (approximately a 3% increase in long-term tensile strain) with reduced crack widths, although it also leads to significantly reduced early-age compressive and tensile strength and chloride ion resistance. However, nanomineral additives are known to improve mechanical strength and durability of HVFA systems. The study emphasizes the effects of different fly ash (FA)/cement ratios on various properties (hydration and microstructural characteristics, transport and mechanical properties) of ECC mixtures designed with different mineral additives. Experimental results confirm that although different optimum levels can be selected to favor various ECC properties, optimum weight fraction of FA is dependent on the mechanism of nanomodification (that is, type of modifier). The optimum level of fly ash weight fraction that yields the highest rate of improvement through nanomodification of ECC varies for different mechanical and transport properties.
Açıklama
Anahtar Kelimeler
chloride ion permeability, engineered cementitious composites, high-volume fly ash, hydration characteristics, mechanical properties, nanomineral additives
Kaynak
Aci Materials Journal
WoS Q Değeri
Q3
Scopus Q Değeri
Q2
Cilt
113
Sayı
6
