Technical Questions

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Aggregate classification by density

Q. Are aggregates classified according to density?


A. Yes. Those used to make normal-density concrete are called normal-density aggregates. Those for low-density concrete (historically known as “lightweight” concrete) that have an air-dried density at 28 days usually in the range of 1440 to 1850 kg/m3 (90 to 115 lb/ft3), are called low-density aggregates. Those for high-density concrete, ranging in density from about 2880 to 5600 kg/m3 (180 to 350 lb/ft3), are called high-density aggregates (ACI 221R, ACI 213R).


References: SP-1(02); ACI E-1(16); ACI 221R-96; ACI 213R-14; ASTM C33

Topics in Concrete: Aggregate; Concrete Fundamentals; Materials; Lightweight

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