Technical Questions

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Why is combined aggregate grading used?

Q. Why is combined aggregate grading used?


A. Combined fine and coarse aggregates grading is specified to ensure that a satisfactory amount of aggregate with a minimum amount of void spaces is obtained. This will enable the use of a minimum amount of paste (water and cementitious material) in concrete, improving the dimensional stability and the durability.


References: SP-1(02); ACI 211.6T-14; E-1(16); ACI 221R-96; ACI 213R-14; ASTM C33

Topics in Concrete: Aggregate; Concrete Fundamentals; Materials; Mixture Proportioning

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