Technical Questions

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Characteristics of aggregate affecting concrete strength

Q. What characteristics of the aggregate are of principal concern in affecting the strength of the concrete?


A. Particle shape, surface texture, size range of the particles, combination of sizes (grading), and strength and elastic modulus of the aggregate are important. A very high modulus aggregate will contribute to volume stability but increase brittleness. A compressible aggregate will increase the volume change due to shrinkage, but will also increase the strain capacity before fracture, thus reducing cracking.


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

Topics in Concrete: Aggregate; Concrete Fundamentals; Materials

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