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How is the slump test made?

Q. How is the slump test made?


A. In accordance with ASTM C143, a mold in the form of a frustum of a cone is filled with the freshly mixed concrete in three layers, each layer being rodded with a bullet-pointed rod. After the mold has been filled, the concrete is struck off and the mold lifted vertically and slowly. The amount by which the mass settles is termed the slump. A low slump indicates a dry consistency and a high slump, a wet consistency.


References: SP-1(02); ACI 238.1R-08; ASTM C143

Topics in Concrete: Concrete Fundamentals; Testing of Concrete

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