Model
Digital Document
Publisher
Florida Atlantic University
Description
Three vital factors, namely environmental protection, savings in costs, and
strength/durability benefits, make it advantageous to incorporate fly ash of controlled
quality and composition in all concrete made from construction demolition (C&D)
recycled aggregate. The specific objective of this research was to compare the
performance characteristics of High-Volume-Fly-Ash (HVFA) structural concrete
containing C&D aggregate with that of normal recycled aggregate concrete containing no
fly ash.
A coordinated experimental program was undertaken which comprised of ( 1)
Compressive and Split Tensile strength tests; (2) ASTM durability tests by measuring
resistance to chloride-ion penetration; and (3) Flexural strength tests on reinforced
concrete beam specimens. Three mix designs were used, all of which had the same
water/cement ratio of 0.45 and the same amount of recycled aggregate/yd^3. Mix 1
contained cement and no fly ash, Mix 2 contained 16% replacement of cement by weight, and Mix 3 contained 40% replacement of cement, called a HVF A mix. Results
indicate that fly ash increases compressive strength, improves both moment carrying
capacity and tension resistance, and increases resistance to chloride-ion attack.
strength/durability benefits, make it advantageous to incorporate fly ash of controlled
quality and composition in all concrete made from construction demolition (C&D)
recycled aggregate. The specific objective of this research was to compare the
performance characteristics of High-Volume-Fly-Ash (HVFA) structural concrete
containing C&D aggregate with that of normal recycled aggregate concrete containing no
fly ash.
A coordinated experimental program was undertaken which comprised of ( 1)
Compressive and Split Tensile strength tests; (2) ASTM durability tests by measuring
resistance to chloride-ion penetration; and (3) Flexural strength tests on reinforced
concrete beam specimens. Three mix designs were used, all of which had the same
water/cement ratio of 0.45 and the same amount of recycled aggregate/yd^3. Mix 1
contained cement and no fly ash, Mix 2 contained 16% replacement of cement by weight, and Mix 3 contained 40% replacement of cement, called a HVF A mix. Results
indicate that fly ash increases compressive strength, improves both moment carrying
capacity and tension resistance, and increases resistance to chloride-ion attack.
Member of