Technical Questions

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The effect of surface texture and cleanness on concrete strength

Q. How do the surface texture and cleanness of the aggregate affect the strength of concrete?


A. The adhesion of the cement paste to the aggregate particles is affected. The presence or absence of adherent soil or clay, the roughness, and the texture of the aggregate affect the adhesion. These characteristics have greater effect on flexural strength than on compressive strength. Soil affects the bond, and excessive fines increase the water demand, which could reduce the strength of concrete.


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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