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Do all fly ashes behave in a similar way?

Q. Do all fly ashes behave in a similar way?


A. No, Class F fly ash has little lime and is purely pozzolanic; Class C fly ash typically has a high lime content and is self-cementing. Fly ashes may also have other chemically reactive constituents. All fly ashes possess pozzolanic properties. They have different characteristics in strength development and resistance to chemical attack.


References: SP-1(02); ACI CT-23; SP-242; ACI 232.2R-03; ASTM C618; ACI PRC-232.4-20

Topics in Concrete: Fly Ash; Concrete Fundamentals; Materials in Concrete; Pozzolan

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