Technical Questions

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What is aggregate?

A.  What is aggregate?


A. Aggregate is granular material, such as sand, gravel, crushed stone, crushed hydraulic cement concrete, or air-cooled iron blast-furnace slag, used with hydraulic cement to produce either concrete or mortar. It is divided into two groups by size, as coarse aggregate (material retained on the 4.75-mm (No. 4) sieve), and fine aggregate (material passing the 4.75-mm (No. 4) sieve) (ACI 221R).


References: SP-1(02); ACI CT-23; E-1(16); ACI 221R-96; ACI 213R-14; ASTM C33

Topics in Concrete: Aggregate; Concrete Fundamentals; Materials

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